Type 2 Diacylglycerol kinase Pleckstrin homology (PH) domain; DGK (also called DAGK) catalyzes the conversion of diacylglycerol (DAG) to phosphatidic acid (PA) utilizing ATP as a source of the phosphate. In non-stimulated cells, DGK activity is low and DAG is used for glycerophospholipid biosynthesis. Upon receptor activation of the phosphoinositide pathway, DGK activity increases which drives the conversion of DAG to PA. DGK acts as a switch by terminating the signalling of one lipid while simultaneously activating signalling by another. There are 9 mammalian DGK isoforms all with conserved catalytic domains and two cysteine rich domains. These are further classified into 5 groups according to the presence of additional functional domains and substrate specificity: Type 1 - DGK-alpha, DGK-beta, DGK-gamma - contain EF-hand motifs and a recoverin homology domain; Type 2 - DGK-delta, DGK-eta, and DGK-kappa- contain a pleckstrin homology domain, two cysteine-rich zinc finger-like structures, and a separated catalytic region; Type 3 - DGK-epsilon - has specificity for arachidonate-containing DAG; Type 4 - DGK-zeta, DGK-iota- contain a MARCKS homology domain, ankyrin repeats, a C-terminal nuclear localization signal, and a PDZ-binding motif; Type 5 - DGK-theta - contains a third cysteine-rich domain, a pleckstrin homology domain and a proline rich region. The type 2 DGKs are present as part of this Metazoan DGK hierarchy. They have a N-terminal PH domain, two cysteine rich domains, followed by bipartite catalytic domains, and a C-terminal SAM domain. Their catalytic domains and perhaps other DGK catalytic domains may function as two independent units in a coordinated fashion. They may also require other motifs for maximal activity because several DGK catalytic domains have very little DAG kinase activity when expressed as isolated subunits. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598   55 IKEGMLTKQNNSFQRSKRRYFKLRGRTLYYAKTAKSIIFDEVDLTDASVAESSTKNVNNSFTVITPCRKLILCADNRKEM 134
Cdd:cd13274    1 IKEGPLLKQTSSFQRWKRRYFKLKGRKLYYAKDSKSLIFEEIDLSDASVAECSTKNVNNSFTVITPFRKLILCAESRKEM 80

                         90
                 ....*....|....*..
gi 25777598  135 EDWIAALKTVQNREHFE 151
Cdd:cd13274   81 EEWISALKTVQQREFYE 97

Diacylglycerol kinase catalytic domain (presumed); Diacylglycerol (DAG) is a second messenger that acts as a protein kinase C activator. DAG can be produced from the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) by a phosphoinositide-specific phospholipase C and by the degradation of phosphatidylcholine (PC) by a phospholipase C or the concerted actions of phospholipase D and phosphatidate phosphohydrolase. This domain is presumed to be the catalytic domain. Bacterial homologues areknown.

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598     323 LVFVNSKSGDNQGVKFLRRFKQLLNPAQVFDLMNGGPHLGLRLFQKFDTF-RILVCGGDGSVGWVLSEIDSLNLHKQC-Q 400
Cdd:smart00046    1 LVFVNPKSGGGKGEKLLRKFRLLLNPRQVFDLTKKGPAVALVIFRDVPDFnRVLVCGGDGTVGWVLNALDKRELPLPEpP 80

                            90       100       110       120
                    ....*....|....*....|....*....|....*....|....*
gi 25777598     401 LGVLPLGTGNDLARVLGWGSACDDDTQLPqILEKLERASTKMLDR 445
Cdd:smart00046   81 VAVLPLGTGNDLARSLGWGGGYDGEKLLK-TLRDALESDTVKLDR 124

second protein kinase C conserved region 1 (C1 domain) found in diacylglycerol kinase delta (DAG kinase delta) and similar proteins; Diacylglycerol (DAG) kinase (EC 2.7.1.107) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. DAG kinase delta, also called 130 kDa diacylglycerol kinase, or diglyceride kinase delta (DGK-delta), is a residential lipid kinase in the endoplasmic reticulum. It promotes lipogenesis and is involved in triglyceride biosynthesis. It is classified as a type II DAG kinase (DGK), containing pleckstrin homology (PH) and sterile alpha motifs (SAM) domains, in addition to C1 and catalytic domains that are present in all DGKs. The SAM domain mediates oligomerization of type II DGKs. DAG kinase delta contains two copies of the C1 domain. This model corresponds to the second one. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 25777598  231 GIAMPHQWLEGNLPVSAKCTVCDKTCGSVLRLQDWRCLWCKAMVHTSCKESLLTKCPLGLC 291
Cdd:cd20893    1 GISMPHQWLEGNLPVSAKCTVCDKTCGSVLRLQDWRCLWCKAMVHTSCKELLLTKCPLGQC 61

Diacylglycerol kinase accessory domain; Diacylglycerol (DAG) is a second messenger that acts as a protein kinase C activator. This domain is assumed to be an accessory domain: its function is unknown.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598    763 VMNNYFGIGLDAKISLDFNNKRDEHPEKCRSRTKNMMWYGVLGTKELLHRTYKNLEQKVLLECDGRPIPLP-SLQGIAVL 841
Cdd:pfam00609    1 VMNNYFSIGVDARIALGFHRLREEHPELFNSRLKNKLIYGVFGFKDMFQRSCKNLIEKVELEVDGKDLPLPkSLEGIVVL 80

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598    842 NIPSYAGGTNFWGGTKEDD-TFAAPSFDDKILEVVAVFGSMQMAVSRVIRLQHHRIAQCRTVKISIlgDEGVPVQVDGEA 920
Cdd:pfam00609   81 NIPSYAGGTDLWGNSKEDGlGFAPQSVDDGLLEVVGLTGALHLGQVQVGLGSAKRIAQGGPIRITT--KKKIPMQVDGEP 158

first protein kinase C conserved region 1 (C1 domain) found in diacylglycerol kinase delta (DAG kinase delta) and similar proteins; Diacylglycerol (DAG) kinase (EC 2.7.1.107) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. DAG kinase delta, also called 130 kDa diacylglycerol kinase, or diglyceride kinase delta (DGK-delta), is a residential lipid kinase in the endoplasmic reticulum. It promotes lipogenesis and is involved in triglyceride biosynthesis. It is classified as a type II DAG kinase (DGK), containing pleckstrin homology (PH) and sterile alpha motifs (SAM) domains, in addition to C1 and catalytic domains that are present in all DGKs. The SAM domain mediates oligomerization of type II DGKs. DAG kinase delta contains two copies of the C1 domain. This model corresponds to the first one. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598  140 ALKTVQNREHFEPTQYSMDHFSGMHNWYACSHARPTYCNVCREALSGVTSHGLSCEVCKFKAHKRCAVRATNNCKWTTLA 219
Cdd:cd20847    1 ALKSVQNREHFESTQYSMDHFSGMHNWYACSHARPTYCNVCREALSGVTSHGLSCEVCKFKAHKRCAVRATNNCKWTTLA 80

                 ....*
gi 25777598  220 SIGKD 224
Cdd:cd20847   81 SIGKD 85

SAM domain of diacylglycerol kinase delta; SAM (sterile alpha motif) domain of DGK-delta subfamily proteins is a protein-protein interaction domain. Proteins of this subfamily are multidomain diacylglycerol kinases with a SAM domain located at the C-terminus. DGK-delta proteins participate in signal transduction. They regulate the level of second messengers such as diacylglycerol and phosphatidic acid. In particular DGK-delta is involved in the regulation of clathrin-dependent endocytosis. The SAM domain of DGK-delta proteins can form high molecular weight homooligomers through head-to-tail interactions as well as heterooligomers with the SAM domain of DGK-eta proteins. The oligomerization plays a role in the regulation of the DGK-delta intracellular localization: it inhibits the translocation of the protein to the plasma membrane from the cytoplasm. The SAM domain also can bind Zn at multiple (not conserved) sites driving the formation of highly ordered large sheets of polymers, thus suggesting that Zn may play important role in the function of DCK-delta.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 25777598 1141 PVHLWGTEEVAAWLEHLSLCEYKDIFTRHDIRGSELLHLERRDLKDLGVTKVGHMKRILCGIKEL 1205
Cdd:cd09575    1 PVHLWGTEEVAAWLEHLSLCEYKDIFTRHDVRGSELLHLERRDLKDLGVTKVGHMKRILCGIKEL 65

Diacylglycerol kinase catalytic domain; Diacylglycerol (DAG) is a second messenger that acts as a protein kinase C activator. The catalytic domain is assumed from the finding of bacterial homologs. YegS is the Escherichia coli protein in this family whose crystal structure reveals an active site in the inter-domain cleft formed by four conserved sequence motifs, revealing a novel metal-binding site. The residues of this site are conserved across the family.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598    321 PLLVFVNSKSGDNQGVKFLRRFKQLLNPAQV-FDLMN-GGPHLGLRLFQKFD---TFRILVCGGDGSVGWVLSEIDslNL 395
Cdd:pfam00781    1 KLLVIVNPKSGGGKGKKLLRKVRPLLNKAGVeVELVLtEGPGDALELAREAAedgYDRIVVAGGDGTVNEVLNGLA--GL 78

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|....*....
gi 25777598    396 HKQCQLGVLPLGTGNDLARVLGWGsacdddTQLPQILEKLERASTKMLD 444
Cdd:pfam00781   79 ATRPPLGIIPLGTGNDFARALGIP------GDPEEALEAILKGQTRPVD 121

SAM domain (Sterile alpha motif);

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 25777598   1142 VHLWGTEEVAAWLEHLSLCEYKDIFTRHDIRGSE-LLHLERRDLKDLGVTKVGHMKRILCGIKEL 1205
Cdd:pfam07647    1 VESWSLESVADWLRSIGLEQYTDNFRDQGITGAElLLRLTLEDLKRLGITSVGHRRKILKKIQEL 65

Pleckstrin homology domain; Domain commonly found in eukaryotic signalling proteins. The domain family possesses multiple functions including the abilities to bind inositol phosphates, and various proteins. PH domains have been found to possess inserted domains (such as in PLC gamma, syntrophins) and to be inserted within other domains. Mutations in Brutons tyrosine kinase (Btk) within its PH domain cause X-linked agammaglobulinaemia (XLA) in patients. Point mutations cluster into the positively charged end of the molecule around the predicted binding site for phosphatidylinositol lipids.

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598      54 IIKEGMLTKQNNSFQRS-KRRYFKLRGRTLYYAKTAKSIIFDE----VDLTDASV---AESSTKNVNNSFTVITPCRK-L 124
Cdd:smart00233    1 VIKEGWLYKKSGGGKKSwKKRYFVLFNSTLLYYKSKKDKKSYKpkgsIDLSGCTVreaPDPDSSKKPHCFEIKTSDRKtL 80

                            90       100
                    ....*....|....*....|..
gi 25777598     125 ILCADNRKEMEDWIAALKTVQN 146
Cdd:smart00233   81 LLQAESEEEREKWVEALRKAIA 102

Protein kinase C conserved region 1 (C1) domains (Cysteine-rich domains); Some bind phorbol esters and diacylglycerol. Some bind RasGTP. Zinc-binding domains.

                            10        20        30        40        50
                    ....*....|....*....|....*....|....*....|....*....|.
gi 25777598     236 HQWLEGNLPVSAKCTVCDKTCGSVlRLQDWRCLWCKAMVHTSCKESLLTKC 286
Cdd:smart00109    1 HKHVFRTFTKPTFCCVCRKSIWGS-FKQGLRCSECKVKCHKKCADKVPKAC 50

PH domain; PH stands for pleckstrin homology.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598     54 IIKEGMLTKQNNSFQRS-KRRYFKLRGRTLYY--------AKTAKSIIfDEVDLTDASVAESSTKNVNNSFTVITPC--- 121
Cdd:pfam00169    1 VVKEGWLLKKGGGKKKSwKKRYFVLFDGSLLYykddksgkSKEPKGSI-SLSGCEVVEVVASDSPKRKFCFELRTGErtg 79

                           90       100
                   ....*....|....*....|..
gi 25777598    122 -RKLILCADNRKEMEDWIAALK 142
Cdd:pfam00169   80 kRTYLLQAESEEERKDWIKAIQ 101

Phosphatidylglycerol kinase, diacylglycerol kinase family [Lipid transport and metabolism, General function prediction only];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598  766 NYFGIGLDAKISLDFNNKRdehpekcrSRTKNMMWYGVLGTKELlhRTYKNLEqkVLLECDGRPIPLPSLQgIAVLNIPS 845
Cdd:COG1597  133 NVAGIGFDAEVVERANRAL--------KRRLGKLAYVLAALRAL--LRYRPFR--LRIELDGEEIEGEALL-VAVGNGPY 199

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598  846 YAGGTNFwggtkeddtFAAPSFDDKILEVVAV----FGSMQMAVSRVIR---LQHHRIAQCRTVKISILGDEGVPVQVDG 918
Cdd:COG1597  200 YGGGLRL---------APDASLDDGLLDVVVVrplsRLRLLRLLPRLLRgrhLRHPGVRYFRAREVEIESDRPLPVQLDG 270

                        170
                 ....*....|....*.
gi 25777598  919 EA-WVQPPGYIRIVHK 933
Cdd:COG1597  271 EPlGLATPLEFEVLPG 286

lipid kinase, YegS/Rv2252/BmrU family; The E. coli member of this family, YegS has been purified and shown to have phosphatidylglycerol kinase activity. The member from M. tuberculosis, Rv2252, has diacylglycerol kinase activity. BmrU from B. subtilis is in an operon with multidrug efflux transporter Bmr, but is uncharacterized. [Unknown function, Enzymes of unknown specificity]

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|.
gi 25777598    367 QKFDTFRILVCGGDGSVGWVLSEIDSLNlhKQCQLGVLPLGTGNDLARVLG 417
Cdd:TIGR00147   54 RKFGVDTVIAGGGDGTINEVVNALIQLD--DIPALGILPLGTANDFARSLG 102

Diacylglycerol kinase accessory domain; Diacylglycerol (DAG) is a second messenger that acts as a protein kinase C activator. This domain is assumed to be an accessory domain: its function is unknown.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598    763 VMNNYFGIGLDAKISLDFNNKRDEHPEKCRSRTKNMMWYGVLGTKELLHRTYKNLEQKVLLECDGRPIPLP-SLQGIAVL 841
Cdd:pfam00609    1 VMNNYFSIGVDARIALGFHRLREEHPELFNSRLKNKLIYGVFGFKDMFQRSCKNLIEKVELEVDGKDLPLPkSLEGIVVL 80

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598    842 NIPSYAGGTNFWGGTKEDD-TFAAPSFDDKILEVVAVFGSMQMAVSRVIRLQHHRIAQCRTVKISIlgDEGVPVQVDGEA 920
Cdd:pfam00609   81 NIPSYAGGTDLWGNSKEDGlGFAPQSVDDGLLEVVGLTGALHLGQVQVGLGSAKRIAQGGPIRITT--KKKIPMQVDGEP 158

first protein kinase C conserved region 1 (C1 domain) found in diacylglycerol kinase delta (DAG kinase delta) and similar proteins; Diacylglycerol (DAG) kinase (EC 2.7.1.107) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. DAG kinase delta, also called 130 kDa diacylglycerol kinase, or diglyceride kinase delta (DGK-delta), is a residential lipid kinase in the endoplasmic reticulum. It promotes lipogenesis and is involved in triglyceride biosynthesis. It is classified as a type II DAG kinase (DGK), containing pleckstrin homology (PH) and sterile alpha motifs (SAM) domains, in addition to C1 and catalytic domains that are present in all DGKs. The SAM domain mediates oligomerization of type II DGKs. DAG kinase delta contains two copies of the C1 domain. This model corresponds to the first one. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598  140 ALKTVQNREHFEPTQYSMDHFSGMHNWYACSHARPTYCNVCREALSGVTSHGLSCEVCKFKAHKRCAVRATNNCKWTTLA 219
Cdd:cd20847    1 ALKSVQNREHFESTQYSMDHFSGMHNWYACSHARPTYCNVCREALSGVTSHGLSCEVCKFKAHKRCAVRATNNCKWTTLA 80

                 ....*
gi 25777598  220 SIGKD 224
Cdd:cd20847   81 SIGKD 85

Diacylglycerol kinase catalytic domain (presumed); Diacylglycerol (DAG) is a second messenger that acts as a protein kinase C activator. DAG can be produced from the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) by a phosphoinositide-specific phospholipase C and by the degradation of phosphatidylcholine (PC) by a phospholipase C or the concerted actions of phospholipase D and phosphatidate phosphohydrolase. This domain is presumed to be the catalytic domain. Bacterial homologues areknown.

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598     323 LVFVNSKSGDNQGVKFLRRFKQLLNPAQVFDLMNGGPHLGLRLFQKFDTF-RILVCGGDGSVGWVLSEIDSLNLHKQC-Q 400
Cdd:smart00046    1 LVFVNPKSGGGKGEKLLRKFRLLLNPRQVFDLTKKGPAVALVIFRDVPDFnRVLVCGGDGTVGWVLNALDKRELPLPEpP 80

                            90       100       110       120
                    ....*....|....*....|....*....|....*....|....*
gi 25777598     401 LGVLPLGTGNDLARVLGWGSACDDDTQLPqILEKLERASTKMLDR 445
Cdd:smart00046   81 VAVLPLGTGNDLARSLGWGGGYDGEKLLK-TLRDALESDTVKLDR 124

second protein kinase C conserved region 1 (C1 domain) found in diacylglycerol kinase delta (DAG kinase delta) and similar proteins; Diacylglycerol (DAG) kinase (EC 2.7.1.107) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. DAG kinase delta, also called 130 kDa diacylglycerol kinase, or diglyceride kinase delta (DGK-delta), is a residential lipid kinase in the endoplasmic reticulum. It promotes lipogenesis and is involved in triglyceride biosynthesis. It is classified as a type II DAG kinase (DGK), containing pleckstrin homology (PH) and sterile alpha motifs (SAM) domains, in addition to C1 and catalytic domains that are present in all DGKs. The SAM domain mediates oligomerization of type II DGKs. DAG kinase delta contains two copies of the C1 domain. This model corresponds to the second one. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 25777598  231 GIAMPHQWLEGNLPVSAKCTVCDKTCGSVLRLQDWRCLWCKAMVHTSCKESLLTKCPLGLC 291
Cdd:cd20893    1 GISMPHQWLEGNLPVSAKCTVCDKTCGSVLRLQDWRCLWCKAMVHTSCKELLLTKCPLGQC 61

first protein kinase C conserved region 1 (C1 domain) found in type II diacylglycerol kinases; Diacylglycerol (DAG) kinase (EC 2.7.1.107) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. Type II DAG kinases (DGKs) contain pleckstrin homology (PH) and sterile alpha motifs (SAM) domains, in addition to C1 and catalytic domains that are present in all DGKs. The SAM domain mediates oligomerization of type II DGKs. Three DGK isozymes (delta, eta and kappa) are classified as type II. DAG kinase delta, also called 130 kDa DAG kinase, or diglyceride kinase delta (DGK-delta), is a residential lipid kinase in the endoplasmic reticulum. It promotes lipogenesis and is involved in triglyceride biosynthesis. DAG kinase eta, also called diglyceride kinase eta (DGK-eta), plays a key role in promoting cell growth. The DAG kinase eta gene, DGKH, is a replicated risk gene of bipolar disorder (BPD). DAG kinase kappa is also called diglyceride kinase kappa (DGK-kappa) or 142 kDa DAG kinase. Members of this family contain two copies of the C1 domain. This model corresponds to the first one. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598  160 FSGMHNWYACSHARPTYCNVCREALSGVTSHGLSCEVCKFKAHKRCAVRATNNCKWTTLA 219
Cdd:cd20800    1 LSGSHNWYACSHARPTYCNVCREALSGVTSHGLSCEVCKFKAHKRCAVKAPNNCKWTTLA 60

second protein kinase C conserved region 1 (C1 domain) found in type II diacylglycerol kinases; Diacylglycerol (DAG) kinase (EC 2.7.1.107) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. Type II DAG kinases (DGKs) contain pleckstrin homology (PH) and sterile alpha motifs (SAM) domains, in addition to C1 and catalytic domains that are present in all DGKs. The SAM domain mediates oligomerization of type II DGKs. Three DGK isozymes (delta, eta and kappa) are classified as type II. DAG kinase delta, also called 130 kDa DAG kinase, or diglyceride kinase delta (DGK-delta), is a residential lipid kinase in the endoplasmic reticulum. It promotes lipogenesis and is involved in triglyceride biosynthesis. DAG kinase eta, also called diglyceride kinase eta (DGK-eta), plays a key role in promoting cell growth. The DAG kinase eta gene, DGKH, is a replicated risk gene of bipolar disorder (BPD). DAG kinase kappa is also called diglyceride kinase kappa (DGK-kappa) or 142 kDa DAG kinase. Members of this family contain two copies of the C1 domain. This model corresponds to the second one. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 25777598  236 HQWLEGNLPVSAKCTVCDKTCGSVLRLQDWRCLWCKAMVHTSCKESLLTKCPLG 289
Cdd:cd20852    1 HQWLEGNLPVSSKCAVCDKTCGSVLRLQDWRCLWCGATVHTACKDSLPTKCSLG 54

Diacylglycerol kinase catalytic domain; Diacylglycerol (DAG) is a second messenger that acts as a protein kinase C activator. The catalytic domain is assumed from the finding of bacterial homologs. YegS is the Escherichia coli protein in this family whose crystal structure reveals an active site in the inter-domain cleft formed by four conserved sequence motifs, revealing a novel metal-binding site. The residues of this site are conserved across the family.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598    321 PLLVFVNSKSGDNQGVKFLRRFKQLLNPAQV-FDLMN-GGPHLGLRLFQKFD---TFRILVCGGDGSVGWVLSEIDslNL 395
Cdd:pfam00781    1 KLLVIVNPKSGGGKGKKLLRKVRPLLNKAGVeVELVLtEGPGDALELAREAAedgYDRIVVAGGDGTVNEVLNGLA--GL 78

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|....*....
gi 25777598    396 HKQCQLGVLPLGTGNDLARVLGWGsacdddTQLPQILEKLERASTKMLD 444
Cdd:pfam00781   79 ATRPPLGIIPLGTGNDFARALGIP------GDPEEALEAILKGQTRPVD 121

second protein kinase C conserved region 1 (C1 domain) found in type III diacylglycerol kinase, DAG kinase epsilon, and similar proteins; Diacylglycerol (DAG) kinase (EC 2.7.1.107) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. DAG kinase epsilon, also called diglyceride kinase epsilon (DGK-epsilon), is the only isoform classified as type III; it possesses a hydrophobic domain in addition to C1 and catalytic domains that are present in all DGKs, and shows selectivity for acyl chains. It is highly selective for arachidonate-containing species of DAG. It may terminate signals transmitted through arachidonoyl-DAG or may contribute to the synthesis of phospholipids with defined fatty acid composition. DAG kinase epsilon contains two copies of the C1 domain. This model corresponds to the second one. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 25777598  236 HQWLEGNLPVSAKCTVCDKTCGSVLRLQDWRCLWCKAMVHTSCKESLLTKCPLGLCKVSVIPP 298
Cdd:cd20853    1 HHWVRGNLPLCSVCCVCNEQCGNQPGLCDYRCCWCQRTVHDDCLAKLPKECDLGAFRNFIVPP 63

SAM domain (Sterile alpha motif);

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 25777598   1142 VHLWGTEEVAAWLEHLSLCEYKDIFTRHDIRGSE-LLHLERRDLKDLGVTKVGHMKRILCGIKEL 1205
Cdd:pfam07647    1 VESWSLESVADWLRSIGLEQYTDNFRDQGITGAElLLRLTLEDLKRLGITSVGHRRKILKKIQEL 65

third protein kinase C conserved region 1 (C1 domain) found in type V diacylglycerol kinase, DAG kinase theta, and similar proteins; Diacylglycerol (DAG) kinase (EC 2.7.1.107) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. DAG kinase theta, also called diglyceride kinase theta (DGK-theta), is the only isoform classified as type V; it contains a pleckstrin homology (PH)-like domain and an additional C1 domain, compared to other DGKs. It may regulate the activity of protein kinase C by controlling the balance between the two signaling lipids, diacylglycerol and phosphatidic acid. DAG kinase theta contains three copies of the C1 domain. This model corresponds to the third one. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 25777598  236 HQWLEGNLPVSAKCTVCDKTCGSVLRLQDWRCLWCKAMVHTSCKESLLTKCPLGLCKVSVIPP 298
Cdd:cd20854    1 HHWREGNLPSNSKCEVCKKSCGSSECLAGMRCEWCGITAHASCYKSLPKECNFGRLRNIILPP 63

Protein kinase C conserved region 1 (C1) domains (Cysteine-rich domains); Some bind phorbol esters and diacylglycerol. Some bind RasGTP. Zinc-binding domains.

                            10        20        30        40        50
                    ....*....|....*....|....*....|....*....|....*....|
gi 25777598     164 HNWYACSHARPTYCNVCREALSGVTSHGLSCEVCKFKAHKRCAVRATNNC 213
Cdd:smart00109    1 HKHVFRTFTKPTFCCVCRKSIWGSFKQGLRCSECKVKCHKKCADKVPKAC 50

Pleckstrin homology domain; Domain commonly found in eukaryotic signalling proteins. The domain family possesses multiple functions including the abilities to bind inositol phosphates, and various proteins. PH domains have been found to possess inserted domains (such as in PLC gamma, syntrophins) and to be inserted within other domains. Mutations in Brutons tyrosine kinase (Btk) within its PH domain cause X-linked agammaglobulinaemia (XLA) in patients. Point mutations cluster into the positively charged end of the molecule around the predicted binding site for phosphatidylinositol lipids.

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598      54 IIKEGMLTKQNNSFQRS-KRRYFKLRGRTLYYAKTAKSIIFDE----VDLTDASV---AESSTKNVNNSFTVITPCRK-L 124
Cdd:smart00233    1 VIKEGWLYKKSGGGKKSwKKRYFVLFNSTLLYYKSKKDKKSYKpkgsIDLSGCTVreaPDPDSSKKPHCFEIKTSDRKtL 80

                            90       100
                    ....*....|....*....|..
gi 25777598     125 ILCADNRKEMEDWIAALKTVQN 146
Cdd:smart00233   81 LLQAESEEEREKWVEALRKAIA 102

Dual Adaptor for Phosphotyrosine and 3-Phosphoinositides Pleckstrin homology (PH) domain; DAPP1 (also known as PHISH/3' phosphoinositide-interacting SH2 domain-containing protein or Bam32) plays a role in B-cell activation and has potential roles in T-cell and mast cell function. DAPP1 promotes B cell receptor (BCR) induced activation of Rho GTPases Rac1 and Cdc42, which feed into mitogen-activated protein kinases (MAPK) activation pathways and affect cytoskeletal rearrangement. DAPP1can also regulate BCR-induced activation of extracellular signal-regulated kinase (ERK), and c-jun NH2-terminal kinase (JNK). DAPP1 contains an N-terminal SH2 domain and a C-terminal pleckstrin homology (PH) domain with a single tyrosine phosphorylation site located centrally. DAPP1 binds strongly to both PtdIns(3,4,5)P3 and PtdIns(3,4)P2. The PH domain is essential for plasma membrane recruitment of PI3K upon cell activation. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598   56 KEGMLTKQNNSFQRSKRRYFKLRGRTLYYAKTAKSII-FDEVDLTDAS-VAESSTKNVNNSFTVITPCRKLILCADNRKE 133
Cdd:cd10573    5 KEGYLTKLGGIVKNWKTRWFVLRRNELKYFKTRGDTKpIRVLDLRECSsVQRDYSQGKVNCFCLVFPERTFYMYANTEEE 84

                 ....*....
gi 25777598  134 MEDWIAALK 142
Cdd:cd10573   85 ADEWVKLLK 93

protein kinase C conserved region 1 (C1 domain) superfamily; The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains. It contains the motif HX12CX2CXnCX2CX4HX2CX7C, where C and H are cysteine and histidine, respectively; X represents other residues; and n is either 13 or 14. C1 has a globular fold with two separate Zn(2+)-binding sites. It was originally discovered as lipid-binding modules in protein kinase C (PKC) isoforms. C1 domains that bind and respond to phorbol esters (PE) and diacylglycerol (DAG) are referred to as typical, and those that do not respond to PE and DAG are deemed atypical. A C1 domain may also be referred to as PKC or non-PKC C1, based on the parent protein's activity. Most C1 domain-containing non-PKC proteins act as lipid kinases and scaffolds, except PKD which acts as a protein kinase. PKC C1 domains play roles in membrane translocation and activation of the enzyme.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 25777598  164 HNWYACSHARPTYCNVCREALSGVTSHGLSCEVCKFKAHKRCAVRATNNC 213
Cdd:cd00029    1 HRFVPTTFSSPTFCDVCGKLIWGLFKQGLKCSDCGLVCHKKCLDKAPSPC 50

second protein kinase C conserved region 1 (C1 domain) found in protein kinase D2 (PKD2) and similar proteins; PKD2, also called PRKD2, HSPC187, or serine/threonine-protein kinase D2 (nPKC-D2), is a serine/threonine-protein kinase that converts transient diacylglycerol (DAG) signals into prolonged physiological effects downstream of PKC, and is involved in the regulation of cell proliferation via MAPK1/3 (ERK1/2) signaling, oxidative stress-induced NF-kappa-B activation, inhibition of HDAC7 transcriptional repression, signaling downstream of T-cell antigen receptor (TCR) and cytokine production, and plays a role in Golgi membrane trafficking, angiogenesis, secretory granule release and cell adhesion. PKD2 contains N-terminal tandem cysteine-rich zinc binding C1 (PKC conserved region 1), central PH (Pleckstrin Homology), and C-terminal catalytic kinase domains. This model corresponds to the second C1 domain. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 25777598  164 HNWYACSHARPTYCNVCREALSGVTSHGLSCEVCKFKAHKRCAVRATNNCKWTTLASIGKDIIEDA 229
Cdd:cd20843   12 HTFVIHSYTRPTVCQFCKKLLKGLFRQGLQCKDCKFNCHKRCATRVPNDCLGETLFNGDLVPMEAA 77

Phosphatidylglycerol kinase, diacylglycerol kinase family [Lipid transport and metabolism, General function prediction only];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598  322 LLVFVNSKSGDNQGVKFLRRFKQLLN----PAQVFDLMNGGPhlGLRLFQK-----FDtfRILVCGGDGSVGWVLSEIds 392
Cdd:COG1597    5 ALLIVNPASGRGRAARLLERLVAALRaaglEVEVLETESPGD--ATELAREaaaegAD--LVVAAGGDGTVNEVANGL-- 78

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|..
gi 25777598  393 lnLHKQCQLGVLPLGTGNDLARVLGWgsacddDTQLPQILEKLERASTKMLD 444
Cdd:COG1597   79 --AGTGPPLGILPLGTGNDFARALGI------PLDPEAALEALLTGRTRRID 122

ArfGAP with coiled-coil, ankyrin repeat and PH domains Pleckstrin homology (PH) domain; ACAP (also called centaurin beta) functions both as a Rab35 effector and as an Arf6-GTPase-activating protein (GAP) by which it controls actin remodeling and membrane trafficking. ACAP contain an NH2-terminal bin/amphiphysin/Rvs (BAR) domain, a phospholipid-binding domain, a PH domain, a GAP domain, and four ankyrin repeats. The AZAPs constitute a family of Arf GAPs that are characterized by an NH2-terminal pleckstrin homology (PH) domain and a central Arf GAP domain followed by two or more ankyrin repeats. On the basis of sequence and domain organization, the AZAP family is further subdivided into four subfamilies: 1) the ACAPs contain an NH2-terminal bin/amphiphysin/Rvs (BAR) domain (a phospholipid-binding domain that is thought to sense membrane curvature), a single PH domain followed by the GAP domain, and four ankyrin repeats; 2) the ASAPs also contain an NH2-terminal BAR domain, the tandem PH domain/GAP domain, three ankyrin repeats, two proline-rich regions, and a COOH-terminal Src homology 3 domain; 3) the AGAPs contain an NH2-terminal GTPase-like domain (GLD), a split PH domain, and the GAP domain followed by four ankyrin repeats; and 4) the ARAPs contain both an Arf GAP domain and a Rho GAP domain, as well as an NH2-terminal sterile-a motif (SAM), a proline-rich region, a GTPase-binding domain, and five PH domains. PMID 18003747 and 19055940 Centaurin can bind to phosphatidlyinositol (3,4,5)P3. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598   56 KEGMLTKQNNSFQRS-KRRYFKLRGRTLYYAKTAKSIIF--DEVDLTDASVAESSTKNVNNSFTVITPCRKLILCADNRK 132
Cdd:cd13250    1 KEGYLFKRSSNAFKTwKRRWFSLQNGQLYYQKRDKKDEPtvMVEDLRLCTVKPTEDSDRRFCFEVISPTKSYMLQAESEE 80

                         90
                 ....*....|..
gi 25777598  133 EMEDWIAALKTV 144
Cdd:cd13250   81 DRQAWIQAIQSA 92

Protein kinase C conserved region 1 (C1) domains (Cysteine-rich domains); Some bind phorbol esters and diacylglycerol. Some bind RasGTP. Zinc-binding domains.

                            10        20        30        40        50
                    ....*....|....*....|....*....|....*....|....*....|.
gi 25777598     236 HQWLEGNLPVSAKCTVCDKTCGSVlRLQDWRCLWCKAMVHTSCKESLLTKC 286
Cdd:smart00109    1 HKHVFRTFTKPTFCCVCRKSIWGS-FKQGLRCSECKVKCHKKCADKVPKAC 50

SAM domain of sphingomyelin synthase related subfamily; SAM (sterile alpha motif) domain of SGMS-like (sphingomyelin synthase) subfamily is a potential protein-protein interaction domain. This group of proteins is related to sphingomyelin synthase 1, and contains an N-terminal SAM domain. The function of SGMS1-like proteins is unknown; they may play a role in sphingolipid metabolism.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 25777598 1142 VHLWGTEEVAAWLEHLSLCEYKDIF-TRHDIRGSELLHLERRDLKD--LGVTKVGHMKRILCGIKELSR 1207
Cdd:cd09515    1 VHEWTCEDVAKWLKKEGFSKYVDLLcNKHRIDGKVLLSLTEEDLRSppLEIKVLGDIKRLWLAIRKLQR 69

SAM domain of Ste50_like (ubc2) subfamily; SAM (sterile alpha motif) domain of Ste50-like (or Ubc2 for Ustilago bypass of cyclase) subfamily is a putative protein-protein interaction domain. This group includes only fungal proteins. Basidiomycetes have an N-terminal SAM domain, central UBQ domain, and C-terminal SH3 domain, while Ascomycetes lack the SH3 domain. Ubc2 of Ustilago maydis is a major virulence and maize pathogenicity factor. It is required for filamentous growth (the budding haploid form of Ustilago maydis is a saprophyte, while filamentous dikaryotic form is a pathogen). Also the Ubc2 protein is involved in the pheromone-responsive morphogenesis via the MAP kinase cascade. The SAM domain is necessary for ubc2 function; deletion of SAM eliminates this function. A Lys-to-Glu mutation in the SAM domain of ubc2 gene induces temperature sensitivity.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 25777598 1149 EVAAWLEHLSLCEYKDIFTRHDIRGSELLHLERRDLKDLGVTKVGHMKRILCGIKEL 1205
Cdd:cd09533    1 DVADWLSSLGLPQYEDQFIENGITGDVLVALDHEDLKEMGITSVGHRLTILKAVYEL 57

Autophagy-related protein 26/Sterol 3-beta-glucosyltransferase Pleckstrin homology (PH) domain, repeat 1; ATG26 (also called UGT51/UDP-glycosyltransferase 51), a member of the glycosyltransferase 28 family, resulting in the biosynthesis of sterol glucoside. ATG26 in decane metabolism and autophagy. There are 32 known autophagy-related (ATG) proteins, 17 are components of the core autophagic machinery essential for all autophagy-related pathways and 15 are the additional components required only for certain pathways or species. The core autophagic machinery includes 1) the ATG9 cycling system (ATG1, ATG2, ATG9, ATG13, ATG18, and ATG27), 2) the phosphatidylinositol 3-kinase complex (ATG6/VPS30, ATG14, VPS15, and ATG34), and 3) the ubiquitin-like protein system (ATG3, ATG4, ATG5, ATG7, ATG8, ATG10, ATG12, and ATG16). Less is known about how the core machinery is adapted or modulated with additional components to accommodate the nonselective sequestration of bulk cytosol (autophagosome formation) or selective sequestration of specific cargos (Cvt vesicle, pexophagosome, or bacteria-containing autophagosome formation). The pexophagosome-specific additions include the ATG30-ATG11-ATG17 receptor-adaptors complex, the coiled-coil protein ATG25, and the sterol glucosyltransferase ATG26. ATG26 is necessary for the degradation of medium peroxisomes. It contains 2 GRAM domains and a single PH domain. PH domains are only found in eukaryotes. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. PH domains also have diverse functions. They are often involved in targeting proteins to the plasma membrane, but few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598   50 RQKTIIKEGMLTKQNNSFQRSKRRYFKLRGRTLYYAKTAKSIIF--DEVDLTDASVAESSTKNVNN--SFTVITPCRKLI 125
Cdd:cd13215   17 RSGAVIKSGYLSKRSKRTLRYTRYWFVLKGDTLSWYNSSTDLYFpaGTIDLRYATSIELSKSNGEAttSFKIVTNSRTYK 96

                         90       100
                 ....*....|....*....|
gi 25777598  126 LCADNRKEMEDWIAALKTVQ 145
Cdd:cd13215   97 FKADSETSADEWVKALKKQI 116

first protein kinase C conserved region 1 (C1 domain) found in diacylglycerol kinase beta (DAG kinase beta) and similar proteins; Diacylglycerol (DAG) kinase (EC 2.7.1.107) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. DAG kinase beta, also called 90 kDa diacylglycerol kinase, or diglyceride kinase beta (DGK-beta), exhibits high phosphorylation activity for long-chain diacylglycerols. It is classified as a type I DAG kinase (DGK), containing EF-hand structures that bind Ca(2+) and a recoverin homology domain, in addition to C1 and catalytic domains that are present in all DGKs. As a type I DGK, it is regulated by calcium binding. DAG kinase beta contains two copies of the C1 domain. This model corresponds to the first one. DGK-beta contains typical C1 domains that bind DAG and phorbol esters. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 25777598  162 GMHNWYACSHARPTYCNVCREALSGVTSHGLSCEVCKFKAHKRCAVRATNNCKWTTLAS 220
Cdd:cd20845    6 GQHVWRLKHFNKPAYCNLCLNMLVGLGKQGLCCSFCKYTVHERCVQRAPASCIKTYVKS 64

Arabidopsis thaliana Pleckstrin homolog (PH) 1 (AtPH1) PH domain; AtPH1 is expressed in all plant tissue and is proposed to be the plant homolog of human pleckstrin. Pleckstrin consists of two PH domains separated by a linker region, while AtPH has a single PH domain with a short N-terminal extension. AtPH1 binds PtdIns3P specifically and is thought to be an adaptor molecule since it has no obvious catalytic functions. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 25777598   56 KEGMLTKQNNSFQRSKRRYFKLRGRTLYYAKTAKSI-------IFDEVDLTDASVAESSTkNVNNSFTVITPCRKLILCA 128
Cdd:cd13276    1 KAGWLEKQGEFIKTWRRRWFVLKQGKLFWFKEPDVTpyskprgVIDLSKCLTVKSAEDAT-NKENAFELSTPEETFYFIA 79