EF-hand, calcium binding motif; A diverse superfamily of calcium sensors and calcium signal modulators; most examples in this alignment model have 2 active canonical EF hands. Ca2+ binding induces a conformational change in the EF-hand motif, leading to the activation or inactivation of target proteins. EF-hands tend to occur in pairs or higher copy numbers.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 19913441  65 AEHVFRTFDTNGDGTIDFREFIIALSVTSRGKLEQKLKWAFSMYDLDGNGYISRSEMLEIVQ 126
Cdd:cd00051   2 LREAFRLFDKDGDGTISADELKAALKSLGEGLSEEEIDEMIREVDKDGDGKIDFEEFLELMA 63

XopAW family type III secretion system calcium-binding effector;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441   63 KFAEHVFRTFDTNGDGTIDFREFIIALSVTSRGKLEQKLKWAFSMYDLDGNGYISRSEMleivqaiykmvSSVMKMP--- 139
Cdd:NF041410  27 QFQKQLFAKLDSDGDGSVSQDELSSALSSKSDDGSLIDLSELFSDLDSDGDGSLSSDEL-----------AAAAPPPppp 95

                         90       100       110
                 ....*....|....*....|....*....|....*....
gi 19913441  140 EDESTPEKRTDKIFRQMDTNNDGKLSLEEFIRGAKSDPS 178
Cdd:NF041410  96 PDQAPSTELADDLLSALDTDGDGSISSDELSAGLTSAGS 134

EF-hand, calcium binding motif; EF-hands are calcium-binding motifs that occur at least in pairs. Links between disease states and genes encoding EF-hands, particularly the S100 subclass, are emerging. Each motif consists of a 12 residue loop flanked on either side by a 12 residue alpha-helix. EF-hands undergo a conformational change unpon binding calcium ions.

                           10        20
                   ....*....|....*....|....*....
gi 19913441    100 KLKWAFSMYDLDGNGYISRSEMLEIVQAI 128
Cdd:smart00054   1 ELKEAFRLFDKDGDGKIDFEEFKDLLKAL 29

EF-hand, calcium binding motif; A diverse superfamily of calcium sensors and calcium signal modulators; most examples in this alignment model have 2 active canonical EF hands. Ca2+ binding induces a conformational change in the EF-hand motif, leading to the activation or inactivation of target proteins. EF-hands tend to occur in pairs or higher copy numbers.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 19913441  65 AEHVFRTFDTNGDGTIDFREFIIALSVTSRGKLEQKLKWAFSMYDLDGNGYISRSEMLEIVQ 126
Cdd:cd00051   2 LREAFRLFDKDGDGTISADELKAALKSLGEGLSEEEIDEMIREVDKDGDGKIDFEEFLELMA 63

calmodulin; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441   73 DTNGDGTIDFREFIIALSVTSR-GKLEQKLKWAFSMYDLDGNGYISRSEMLEIvqaiykMVSSVMKMPEDEstpekrTDK 151
Cdd:PTZ00184  57 DADGNGTIDFPEFLTLMARKMKdTDSEEEIKEAFKVFDRDGNGFISAAELRHV------MTNLGEKLTDEE------VDE 124

                         90       100
                 ....*....|....*....|
gi 19913441  152 IFRQMDTNNDGKLSLEEFIR 171
Cdd:PTZ00184 125 MIREADVDGDGQINYEEFVK 144

EF-hand domain pair;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 19913441    98 EQKLKWAFSMYDLDGNGYISRSEMLEIVQAIYkmvssvmkmpEDESTPEKRTDKIFRQMDTNNDGKLSLEEFIRGAK 174
Cdd:pfam13499   1 EEKLKEAFKLLDSDGDGYLDVEELKKLLRKLE----------EGEPLSDEEVEELFKEFDLDKDGRISFEEFLELYS 67

EF-hand, calcium binding motif, found in reticulocalbin-2 (RCN2) mainly from protostomes; This family corresponds to a group of uncharacterized RCN2-like proteins, which are mainly found in protostomes. Although their biological function remains unclear, they show high sequence similarity with RCN2 (also known as E6BP or TCBP-49), which is an endoplasmic reticulum resident low-affinity Ca2+-binding protein that has been implicated in immunity, redox homeostasis, cell cycle regulation and coagulation. Members in this family contain six copies of the EF-hand Ca2+-binding motif, but may lack a C-terminal His-Asp-Glu-Leu (HDEL) tetrapeptide that is required for retention of RCN2 in the endoplasmic reticulum (ER).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  41 GHLTVDEFKKIYAnffPYGDASKFA---EHVFRTFDTNGDGTIDFREFI--IALSVTSRGKLEQKLKWAFSmYDLDGNGY 115
Cdd:cd16227 137 GKLDKTEFSAFQH---PEEYPHMHPvliEQTLRDKDKDNDGFISFQEFLgdRAGHEDKEWLLVEKDRFDED-YDKDGDGK 212

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|....*
gi 19913441 116 ISRSEMLEIVqaiykmvssvmkMPEDESTPEKRTDKIFRQMDTNNDGKLSLEEFI 170
Cdd:cd16227 213 LDGEEILSWL------------VPDNEEIAEEEVDHLFASADDDHDDRLSFDEIL 255

EF-hand domain pair;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 19913441    68 VFRTFDTNGDGTIDFREFIIALSVTSRGK--LEQKLKWAFSMYDLDGNGYISRSEMLEIVQ 126
Cdd:pfam13499   7 AFKLLDSDGDGYLDVEELKKLLRKLEEGEplSDEEVEELFKEFDLDKDGRISFEEFLELYS 67

EF-hand-like motif found in the dystrophin/dystrobrevin/dystrotelin family; The dystrophin/dystrobrevin/dystrotelin family has been characterized by a compact cluster of domains comprising four EF-hand-like motifs and a ZZ-domain, followed by a looser region with two coiled-coils. Dystrophin is the founder member of this family. It is a sub-membrane cytoskeletal protein associated with the inner surface membrane. Dystrophin and its close paralog utrophin have a large N-terminal extension of actin-binding CH domains, up to 24 spectrin repeats, and a WW domain. Its further paralog, dystrophin-related protein 2 (DRP-2), retains only two of the spectrin repeats. Dystrophin, utrophin or DRP2 can form the core of a membrane-bound complex consisting of dystroglycan, sarcoglycans and syntrophins, known as the dystrophin-glycoprotein complex (DGC) that plays an important role in brain development and disease, as well as in the prevention of muscle damage. Dystrobrevins, including alpha- and beta-dystrobrevin, lack the large N-terminal extension found in dystrophin, but alpha-dystrobrevin has a characteristic C-terminal extension. Dystrobrevins are part of the DGC. They physically associate with members of the dystrophin family and with the syntrophins through their homologous C-terminal coiled coil motifs. In contrast, dystrotelins lack both the large N-terminal extension found in dystrophin and the obvious syntrophin-binding sites (SBSs). Dystrotelins are not critical for mammalian development. They may be involved in other forms of cytokinesis. Moreover, dystrotelin is unable to heterodimerize with members of the dystrophin or dystrobrevin families, or to homodimerize.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 19913441  71 TFDTNGDGTIDFREFIIALSVTSRGKLEQKLKWAFSMYDlDGNGYISRSEMLEIVQAIYKMVS 133
Cdd:cd15901  62 LYDRNRTGCIRLLSVKIALITLCAASLLDKYRYLFGQLA-DSSGFISRERLTQFLQDLLQIPD 123

Penta-EF hand, calcium binding motifs, found in Group I PEF proteins; The family corresponds to Group I PEF proteins that have been found not only in higher animals but also in lower animals, plants, fungi and protists. Group I PEF proteins include apoptosis-linked gene 2 protein (ALG-2), peflin and similar proteins. ALG-2, also termed programmed cell death protein 6 (PDCD6), is a widely expressed calcium-binding modulator protein associated with cell proliferation and death, as well as cell survival. It forms a homodimer in the cell or a heterodimer with its closest paralog peflin. Among the PEF proteins, ALG-2 can bind three Ca2+ ions through its EF1, EF3, and EF5 hands, where it is unique in that its EF5 hand binds Ca2+ ion in a canonical coordination. Peflin is a ubiquitously expressed 30-kD PEF protein containing five EF-hand motifs in its C-terminal domain and a longer N-terminal hydrophobic domain (NHB domain) than any other member of the PEF family. The NHB domain harbors nine repeats of a nonapeptide (A/PPGGPYGGP). Peflin may modulate the function of ALG-2 in Ca2+ signaling. It exists only as a heterodimer with ALG-2, and binds two Ca2+ ions through its EF1 and EF3 hands. Its additional EF5 hand is unpaired and does not bind Ca2+ ion but mediates the heterodimerization with ALG-2. The dissociation of heterodimer occurs in the presence of Ca2+.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  26 ELQEWYKGFLKDCpTGHLTVDEFKKIYANffpyGDASKFAEHV----FRTFDTNGDGTIDFREFIialsvtsrgKLEQKL 101
Cdd:cd16180   1 ELRRIFQAVDRDR-SGRISAKELQRALSN----GDWTPFSIETvrlmINMFDRDRSGTINFDEFV---------GLWKYI 66

                        90       100       110       120       130       140       150
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 19913441 102 K-W--AFSMYDLDGNGYISRSEMLEIVQAI-YKMVSSVmkmpedestpekrTDKIFRQMDTNNDGKLSLEEFIR 171
Cdd:cd16180  67 QdWrrLFRRFDRDRSGSIDFNELQNALSSFgYRLSPQF-------------VQLLVRKFDRRRRGSISFDDFVE 127

EF-hand, calcium binding motif, found in the hexa-EF hand proteins family; The hexa-EF hand proteins family, also named the calbindin sub-family, contains a group of six EF-hand Ca2+-binding proteins, including calretinin (CR, also termed 29 kDa calbindin), calbindin D28K (CB, also termed vitamin D-dependent calcium-binding protein, avian-type), and secretagogin (SCGN). CR is a cytosolic hexa-EF-hand calcium-binding protein predominantly expressed in a variety of normal and tumorigenic t-specific neurons of the central and peripheral nervous system. It is a multifunctional protein implicated in many biological processes, including cell proliferation, differentiation, and cell death. CB is highly expressed in brain tissue. It is a strong calcium-binding and buffering protein responsible for preventing a neuronal death as well as maintaining and controlling calcium homeostasis. SCGN is a six EF-hand calcium-binding protein expressed in neuroendocrine, pancreatic endocrine and retinal cells. It plays a crucial role in cell apoptosis, receptor signaling and differentiation. It is also involved in vesicle secretion through binding to various proteins, including interacts with SNAP25, SNAP23, DOC2alpha, ARFGAP2, rootletin, KIF5B, beta-tubulin, DDAH-2, ATP-synthase and myeloid leukemia factor 2. SCGN functions as a Ca2+ sensor/coincidence detector modulating vesicular exocytosis of neurotransmitters, neuropeptides or hormones. Although the family members share a significant amount of secondary sequence homology, they display altered structural and biochemical characteristics, and operate in distinct fashions. CB contains six EF-hand motifs in a single globular domain, where EF-hands 1, 3, 4, 5 bind four calcium ions. CR contains six EF-hand motifs within two independent domains, CR I-II and CR III-VI. They harbor two and four EF-hand motifs, respectively. The first 5 EF-hand motifs are capable of binding calcium ions, while the EF-hand 6 is inactive. SCGN consists of the three globular domains each of which contains a pair of EF-hand motifs. Human SCGN simultaneously binds four calcium ions through its EF-hands 3, 4, 5 and 6 in one high affinity and three low affinity calcium-binding sites. In contrast, SCGNs in other lower eukaryotes, such as D. rerio, X. laevis, M. domestica, G. gallus, O. anatinus, are fully competent in terms of six calcium-binding.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  32 KGFLKDCPTGHLTVDEFKKIyanffpygdaSKFAEHVFRTFDTNGDGTIDFREFIIALSV------TSRGKLEQKLKW-- 103
Cdd:cd15902 113 KGFLKDLLLKNKKHVSPPKL----------DEYTKLILKEFDANKDGKLELDEMAKLLPVqenfllKFQILGAMDLTKed 182

                        90       100       110       120       130       140
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 19913441 104 ---AFSMYDLDGNGYISRSEMLEIVQAIYKMVSSVMKMPEDestpEKRTDKIFRQMDTNNDGKLSLEE 168
Cdd:cd15902 183 fekVFEHYDKDNNGVIEGNELDALLKDLLEKNKADIDKPDL----ENFRDAILRACDKNKDGKIQKTE 246

EF-hand, calcium binding motif, found in Drosophila melanogaster calbindin-32 (CBN) and similar proteins; CBN, the product of the cbn gene, is a Drosophila homolog to vertebrate neuronal six EF-hand calcium binding proteins. It is expressed through most of ontogenesis with a selective distribution in the nervous system and in a few small adult thoracic muscles. Its precise biological role remains unclear. CBN contains six EF-hand motifs, but some of them may not bind calcium ions due to the lack of key residues.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  64 FAEHVFRTFDTNGDGTIDFREFIIALSVTSRGKLEQKLKWA-----------FSMYDLDGNGYISRSEM-------LEIV 125
Cdd:cd16179 142 YTDTILQLFDRNKDGKLQLSEMARLLPVKENFLCRPIFKGAgkltredidrvFALYDRDNNGTIENEELtgflkdlLELV 221

                        90       100       110       120
                ....*....|....*....|....*....|....*....|...
gi 19913441 126 QAIYkmvssvmkmpeDESTPEKRTDKIFRQMDTNNDGKLSLEE 168
Cdd:cd16179 222 QEDY-----------DEQDLEEFKEIILRGWDFNNDGKISRKE 253

EF-hand, calcium binding motif, found in CREC-EF hand family; The CREC (Cab45/reticulocalbin/ERC45/calumenin)-EF hand family contains a group of six EF-hand, low-affinity Ca2+-binding proteins, including reticulocalbin (RCN-1), ER Ca2+-binding protein of 55 kDa (ERC-55, also known as TCBP-49 or E6BP), reticulocalbin-3 (RCN-3), Ca2+-binding protein of 45 kDa (Cab45 and its splice variant Cab45b), and calumenin ( also known as crocalbin or CBP-50). The proteins are not only localized in various parts of the secretory pathway, but also found in the cytosolic compartment and at the cell surface. They interact with different ligands or proteins and have been implicated in the secretory process, chaperone activity, signal transduction as well as in a large variety of disease processes.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  70 RTFDTNGDGTIDFREFIiALSVTSRGKlEQKLKWAFS-------MYDLDGNGYISRSEMLEIVqaiykmvssvmkMPEDE 142
Cdd:cd15899 167 EDLDKNGDGFISLEEFI-SDPYSADEN-EEEPEWVKVekerfveLRDKDKDGKLDGEELLSWV------------DPSNQ 232

                        90       100
                ....*....|....*....|....*.
gi 19913441 143 STPEKRTDKIFRQMDTNNDGKLSLEE 168
Cdd:cd15899 233 EIALEEAKHLIAESDENKDGKLSPEE 258

EF-hand domain pair;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 19913441    39 PTGHLTVDEFKKIYANFFPYGDASKFAEHVFRTFDTNGDGTIDFREFIIAL 89
Cdd:pfam13833   1 EKGVITREELKRALALLGLKDLSEDEVDILFREFDTDGDGYISFDEFCVLL 51

EF-hand, calcium binding motif, found in the hexa-EF hand proteins family; The hexa-EF hand proteins family, also named the calbindin sub-family, contains a group of six EF-hand Ca2+-binding proteins, including calretinin (CR, also termed 29 kDa calbindin), calbindin D28K (CB, also termed vitamin D-dependent calcium-binding protein, avian-type), and secretagogin (SCGN). CR is a cytosolic hexa-EF-hand calcium-binding protein predominantly expressed in a variety of normal and tumorigenic t-specific neurons of the central and peripheral nervous system. It is a multifunctional protein implicated in many biological processes, including cell proliferation, differentiation, and cell death. CB is highly expressed in brain tissue. It is a strong calcium-binding and buffering protein responsible for preventing a neuronal death as well as maintaining and controlling calcium homeostasis. SCGN is a six EF-hand calcium-binding protein expressed in neuroendocrine, pancreatic endocrine and retinal cells. It plays a crucial role in cell apoptosis, receptor signaling and differentiation. It is also involved in vesicle secretion through binding to various proteins, including interacts with SNAP25, SNAP23, DOC2alpha, ARFGAP2, rootletin, KIF5B, beta-tubulin, DDAH-2, ATP-synthase and myeloid leukemia factor 2. SCGN functions as a Ca2+ sensor/coincidence detector modulating vesicular exocytosis of neurotransmitters, neuropeptides or hormones. Although the family members share a significant amount of secondary sequence homology, they display altered structural and biochemical characteristics, and operate in distinct fashions. CB contains six EF-hand motifs in a single globular domain, where EF-hands 1, 3, 4, 5 bind four calcium ions. CR contains six EF-hand motifs within two independent domains, CR I-II and CR III-VI. They harbor two and four EF-hand motifs, respectively. The first 5 EF-hand motifs are capable of binding calcium ions, while the EF-hand 6 is inactive. SCGN consists of the three globular domains each of which contains a pair of EF-hand motifs. Human SCGN simultaneously binds four calcium ions through its EF-hands 3, 4, 5 and 6 in one high affinity and three low affinity calcium-binding sites. In contrast, SCGNs in other lower eukaryotes, such as D. rerio, X. laevis, M. domestica, G. gallus, O. anatinus, are fully competent in terms of six calcium-binding.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441 105 FSMYDLDGNGYISRSEMLEIVQAIYKMVSSvMKMPEDESTPEKRTdkIFRQMDTNNDGKLSLEEFIRGAKSDPSIVRLLQ 184
Cdd:cd15902   5 WMHFDADGNGYIEGKELDSFLRELLKALNG-KDKTDDEVAEKKKE--FMEKYDENEDGKIEIRELANILPTEENFLLLFR 81

                ....*...
gi 19913441 185 CDPSSASQ 192
Cdd:cd15902  82 REQPLISS 89

Calgranulins: S-100 domain found in proteins belonging to the Calgranulin subgroup of the S100 family of EF-hand calcium-modulated proteins, including S100A8, S100A9, and S100A12 . Note that the S-100 hierarchy, to which this Calgranulin group belongs, contains only S-100 EF-hand domains, other EF-hands have been modeled separately. These proteins are expressed mainly in granulocytes, and are involved in inflammation, allergy, and neuritogenesis, as well as in host-parasite response. Calgranulins are modulated not only by calcium, but also by other metals such as zinc and copper. Structural data suggested that calgranulins may exist in multiple structural forms, homodimers, as well as hetero-oligomers. For example, the S100A8/S100A9 complex called calprotectin plays important roles in the regulation of inflammatory processes, wound repair, and regulating zinc-dependent enzymes as well as microbial growth.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 19913441  43 LTVDEFKKIY----ANFFPYGDASKFAEHVFRTFDTNGDGTIDFREFII 87
Cdd:cd05030  27 LYKKEFKQLVekelPNFLKKEKNQKAIDKIFEDLDTNQDGQLSFEEFLV 75

EF-hand, calcium binding motif, found in the hexa-EF hand proteins family; The hexa-EF hand proteins family, also named the calbindin sub-family, contains a group of six EF-hand Ca2+-binding proteins, including calretinin (CR, also termed 29 kDa calbindin), calbindin D28K (CB, also termed vitamin D-dependent calcium-binding protein, avian-type), and secretagogin (SCGN). CR is a cytosolic hexa-EF-hand calcium-binding protein predominantly expressed in a variety of normal and tumorigenic t-specific neurons of the central and peripheral nervous system. It is a multifunctional protein implicated in many biological processes, including cell proliferation, differentiation, and cell death. CB is highly expressed in brain tissue. It is a strong calcium-binding and buffering protein responsible for preventing a neuronal death as well as maintaining and controlling calcium homeostasis. SCGN is a six EF-hand calcium-binding protein expressed in neuroendocrine, pancreatic endocrine and retinal cells. It plays a crucial role in cell apoptosis, receptor signaling and differentiation. It is also involved in vesicle secretion through binding to various proteins, including interacts with SNAP25, SNAP23, DOC2alpha, ARFGAP2, rootletin, KIF5B, beta-tubulin, DDAH-2, ATP-synthase and myeloid leukemia factor 2. SCGN functions as a Ca2+ sensor/coincidence detector modulating vesicular exocytosis of neurotransmitters, neuropeptides or hormones. Although the family members share a significant amount of secondary sequence homology, they display altered structural and biochemical characteristics, and operate in distinct fashions. CB contains six EF-hand motifs in a single globular domain, where EF-hands 1, 3, 4, 5 bind four calcium ions. CR contains six EF-hand motifs within two independent domains, CR I-II and CR III-VI. They harbor two and four EF-hand motifs, respectively. The first 5 EF-hand motifs are capable of binding calcium ions, while the EF-hand 6 is inactive. SCGN consists of the three globular domains each of which contains a pair of EF-hand motifs. Human SCGN simultaneously binds four calcium ions through its EF-hands 3, 4, 5 and 6 in one high affinity and three low affinity calcium-binding sites. In contrast, SCGNs in other lower eukaryotes, such as D. rerio, X. laevis, M. domestica, G. gallus, O. anatinus, are fully competent in terms of six calcium-binding.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  24 DHELQEWYKGFLKDCPTGHLTVDEFKKIYANFFpygdaskfaehvfRTFDTNGDGTIDFRE----------FIIALSVTS 93
Cdd:cd15902  18 GKELDSFLRELLKALNGKDKTDDEVAEKKKEFM-------------EKYDENEDGKIEIRElanilpteenFLLLFRREQ 84

                        90       100       110       120       130       140       150
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 19913441  94 RGKLEQKLKWAFSMYDLDGNGYISRSEMleivQAIYKMVSSVMKMPEDESTPEKRTDKIFRQMDTNNDGKLSLEEFIR 171
Cdd:cd15902  85 PLISSVEFMKIWRKYDTDGSGFIEAKEL----KGFLKDLLLKNKKHVSPPKLDEYTKLILKEFDANKDGKLELDEMAK 158

EF-hand, calcium binding motif, found in reticulocalbin-2 (RCN2) mainly from protostomes; This family corresponds to a group of uncharacterized RCN2-like proteins, which are mainly found in protostomes. Although their biological function remains unclear, they show high sequence similarity with RCN2 (also known as E6BP or TCBP-49), which is an endoplasmic reticulum resident low-affinity Ca2+-binding protein that has been implicated in immunity, redox homeostasis, cell cycle regulation and coagulation. Members in this family contain six copies of the EF-hand Ca2+-binding motif, but may lack a C-terminal His-Asp-Glu-Leu (HDEL) tetrapeptide that is required for retention of RCN2 in the endoplasmic reticulum (ER).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  73 DTNGDGTIDFREFI--IALSVTSRGKLEQKLKwaFSMYDLDGNGYISRSEmleIVQAIYKMVSSVMKMPEDESTPEKRT- 149
Cdd:cd16227  46 DLNDDGFIDRKELKawILRSFKMLDEEEANER--FEEADEDGDGKVTWEE---YLADSFGYDDEDNEEMIKDSTEDDLKl 120

                        90       100
                ....*....|....*....|....*
gi 19913441 150 ---DKI-FRQMDTNNDGKLSLEEFI 170
Cdd:cd16227 121 ledDKEmFEAADLNKDGKLDKTEFS 145

EF-hand, calcium binding motif, found in calbindin (CB); CB, also termed calbindin D28, or D-28K, or avian-type vitamin D-dependent calcium-binding protein, is a unique intracellular calcium binding protein that functions as both a calcium sensor and buffer in eukaryotic cells, which undergoes a conformational change upon calcium binding and protects cells against insults of high intracellular calcium concentration. CB is highly expressed in brain and sensory neurons. It plays essential roles in neural functioning, altering synaptic interactions in the hippocampus, modulating calcium channel activity, calcium transients, and intrinsic neuronal firing activity. It prevents a neuronal death, as well as maintains and controls calcium homeostasis. CB also modulates the activity of proteins participating in the development of neurodegenerative disorders such as Alzheimer's disease, Huntington's disease, and bipolar disorder. Moreover, CB interacts with Ran-binding protein M, a protein known to involve in microtubule function. It also interacts with alkaline phosphatase and myo-inositol monophosphatase, as well as caspase 3, an enzyme that plays an important role in the regulation of apoptosis. CB contains six EF-hand motifs in a single globular domain, where EF-hands 1, 3, 4, 5 bind four calcium ions with high affinity.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 19913441 104 AFSMYDLDGNGYISRSEMLEIVQAIYKMVssvmKMPEDESTPEKRTDKIFRQMDTNNDGKLSLEEFIR 171
Cdd:cd16176  90 TWRKYDADHSGFIEADELKSFLKDLLKKA----NKPFDESKLEEYTHTMLKMFDSNNDGKLGLTEMAR 153

EF-hand, calcium binding motif, found in peflin and similar proteins; Peflin, also termed penta-EF hand (PEF) protein with a long N-terminal hydrophobic domain, or penta-EF hand domain-containing protein 1, is a ubiquitously expressed 30-kD PEF protein containing five EF-hand motifs in its C-terminal domain and a longer N-terminal hydrophobic domain (NHB domain) than any other member of the PEF family. The NHB domain harbors nine repeats of a nonapeptide (A/PPGGPYGGP). Peflin may modulate the function of ALG-2 in Ca2+ signaling. It exists only as a heterodimer with ALG-2, and binds two Ca2+ ions through its EF1 and EF3 hands. Its additional EF5 hand is unpaired and does not bind Ca2+ ion but mediates the heterodimerization with ALG-2. The dissociation of heterodimer occurs in the presence of Ca2+. In lower vertebrates, peflin may interact with transient receptor potential N (TRPN1), suggesting a potential role of peflin in fast transducer channel adaptation.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  26 ELQEWYKGFLKDcPTGHLTVDEFKKIYANffpyGDASKFAEH----VFRTFDTNGDGTIDFREFiialsvTSRGKLEQKL 101
Cdd:cd16184   1 EVQQWFQAVDRD-RSGKISAKELQQALVN----GNWSHFNDEtcrlMIGMFDKDKSGTIDIYEF------QALWNYIQQW 69

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441 102 KWAFSMYDLDGNGYISRSEMleiVQAIYKM--------VSSVM---------KMPEDE----STPEKRTDKIFRQMDTNN 160
Cdd:cd16184  70 KQVFQQFDRDRSGSIDENEL---HQALSQMgyrlspqfVQFLVskydprarrSLTLDQfiqvCVQLQSLTDAFRQRDTQM 146

                       170
                ....*....|..
gi 19913441 161 DG--KLSLEEFI 170
Cdd:cd16184 147 TGtiTISYEDFL 158

EF-hand, calcium binding motif; EF-hands are calcium-binding motifs that occur at least in pairs. Links between disease states and genes encoding EF-hands, particularly the S100 subclass, are emerging. Each motif consists of a 12 residue loop flanked on either side by a 12 residue alpha-helix. EF-hands undergo a conformational change unpon binding calcium ions.

                           10        20
                   ....*....|....*....|...
gi 19913441     68 VFRTFDTNGDGTIDFREFIIALS 90
Cdd:smart00054   5 AFRLFDKDGDGKIDFEEFKDLLK 27

EF-hand motif found in eukaryotic phosphoinositide-specific phospholipase C (PI-PLC, EC 3.1.4.11) isozymes; PI-PLC isozymes are signaling enzymes that hydrolyze the membrane phospholipids phosphatidylinositol-4,5-bisphosphate (PIP2) to generate two important second messengers in eukaryotic signal transduction cascades, Inositol 1,4,5-trisphosphate (InsP3) and diacylglycerol (DAG). InsP3 triggers inflow of calcium from intracellular stores, while DAG, together with calcium, activates protein kinase C, which goes on to phosphorylate other molecules, leading to altered cellular activity. Calcium is required for the catalysis. This family corresponds to the four EF-hand motifs containing PI-PLC isozymes, including PI-PLC-beta (1-4), -gamma (1-2), -delta (1,3,4), -epsilon (1), -zeta (1), eta (1-2). Lower eukaryotes such as yeast and slime molds contain only delta-type isozymes. In contrast, other types of isoforms present in higher eukaryotes. This family also includes 1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase 1 (PLC1) from fungi. Some homologs from plants contain only two atypical EF-hand motifs and they are not included. All PI-PLC isozymes except sperm-specific PI-PLC-zeta share a core set of domains, including an N-terminal pleckstrin homology (PH) domain, four atypical EF-hand motifs, a PLC catalytic core, and a single C2 domain. PI-PLC-zeta lacks the PH domain. The PLC catalytic core domain is a TIM barrel with two highly conserved regions (X and Y) split by a highly degenerate linker sequence. Most of EF-hand motifs found in PI-PLCs consist of a helix-loop-helix structure, but lack residues critical to metal binding. Moreover, the EF-hand region of most of PI-PLCs may have an important regulatory function, but it has yet to be identified. However, PI-PLC-zeta is a key exception. It is responsible for Ca2+ oscillations in fertilized oocytes and exhibits a high sensitivity to Ca2+ mediated through its EF-hand domain. In addition, PI-PLC-eta2 shows a canonical EF-loop directing Ca2+-sensitivity and thus can amplify transient Ca2+ signals. Also it appears that PI-PLC-delta1 can regulate the binding of PH domain to PIP2 in a Ca2+-dependent manner through its functionally important EF-hand domains. PI-PLCs can be activated by a variety of extracellular ligands, such as growth factors, hormones, cytokines and lipids. Their activation has been implicated in tumorigenesis and/or metastasis linked to migration, proliferation, growth, inflammation, angiogenesis and actin cytoskeleton reorganization. PI-PLC-beta isozymes are activated by G-protein coupled receptor (GPCR) through different mechanisms. However, PI-PLC-gamma isozymes are activated by receptor tyrosine kinase (RTK), such as Rho and Ras GTPases. In contrast, PI-PLC-epsilon are activated by both GPCR and RTK. PI-PLC-delta1 and PLC-eta 1 are activated by GPCR-mediated calcium mobilization. The activation mechanism for PI-PLC-zeta remains unclear.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  41 GHLTVDEFKKIYANFFPYGDaSKFAEHVFRTFDTNGDGTIDFREFIIAL-SVTSRGKLEQklkwAFSMYDLDGNGYISRS 119
Cdd:cd15898  15 GKLSLKEIKKLLKRLNIRVS-EKELKKLFKEVDTNGDGTLTFDEFEELYkSLTERPELEP----IFKKYAGTNRDYMTLE 89

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|...
gi 19913441 120 EMLEIVQAIykmvssvmkmpEDESTPEKRTDKIFRQMDTN-NDGKLSLEEFIR 171
Cdd:cd15898  90 EFIRFLREE-----------QGENVSEEECEELIEKYEPErENRQLSFEGFTN 131

EF-hand domain;

                          10        20
                  ....*....|....*....|....*....
gi 19913441   100 KLKWAFSMYDLDGNGYISRSEMLEIVQAI 128
Cdd:pfam13405   1 ELREAFKLFDKDGDGKISLEELRKALRSL 29

EF-hand motif found in eukaryotic phosphoinositide-specific phospholipase C (PI-PLC, EC 3.1.4.11) isozymes; PI-PLC isozymes are signaling enzymes that hydrolyze the membrane phospholipids phosphatidylinositol-4,5-bisphosphate (PIP2) to generate two important second messengers in eukaryotic signal transduction cascades, Inositol 1,4,5-trisphosphate (InsP3) and diacylglycerol (DAG). InsP3 triggers inflow of calcium from intracellular stores, while DAG, together with calcium, activates protein kinase C, which goes on to phosphorylate other molecules, leading to altered cellular activity. Calcium is required for the catalysis. This family corresponds to the four EF-hand motifs containing PI-PLC isozymes, including PI-PLC-beta (1-4), -gamma (1-2), -delta (1,3,4), -epsilon (1), -zeta (1), eta (1-2). Lower eukaryotes such as yeast and slime molds contain only delta-type isozymes. In contrast, other types of isoforms present in higher eukaryotes. This family also includes 1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase 1 (PLC1) from fungi. Some homologs from plants contain only two atypical EF-hand motifs and they are not included. All PI-PLC isozymes except sperm-specific PI-PLC-zeta share a core set of domains, including an N-terminal pleckstrin homology (PH) domain, four atypical EF-hand motifs, a PLC catalytic core, and a single C2 domain. PI-PLC-zeta lacks the PH domain. The PLC catalytic core domain is a TIM barrel with two highly conserved regions (X and Y) split by a highly degenerate linker sequence. Most of EF-hand motifs found in PI-PLCs consist of a helix-loop-helix structure, but lack residues critical to metal binding. Moreover, the EF-hand region of most of PI-PLCs may have an important regulatory function, but it has yet to be identified. However, PI-PLC-zeta is a key exception. It is responsible for Ca2+ oscillations in fertilized oocytes and exhibits a high sensitivity to Ca2+ mediated through its EF-hand domain. In addition, PI-PLC-eta2 shows a canonical EF-loop directing Ca2+-sensitivity and thus can amplify transient Ca2+ signals. Also it appears that PI-PLC-delta1 can regulate the binding of PH domain to PIP2 in a Ca2+-dependent manner through its functionally important EF-hand domains. PI-PLCs can be activated by a variety of extracellular ligands, such as growth factors, hormones, cytokines and lipids. Their activation has been implicated in tumorigenesis and/or metastasis linked to migration, proliferation, growth, inflammation, angiogenesis and actin cytoskeleton reorganization. PI-PLC-beta isozymes are activated by G-protein coupled receptor (GPCR) through different mechanisms. However, PI-PLC-gamma isozymes are activated by receptor tyrosine kinase (RTK), such as Rho and Ras GTPases. In contrast, PI-PLC-epsilon are activated by both GPCR and RTK. PI-PLC-delta1 and PLC-eta 1 are activated by GPCR-mediated calcium mobilization. The activation mechanism for PI-PLC-zeta remains unclear.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 19913441 100 KLKWAFSMYDLDGNGYISRSEMLEIVQAIykmvssvmkmpeDESTPEKRTDKIFRQMDTNNDGKLSLEEFIR 171
Cdd:cd15898   1 WLRRQWIKADKDGDGKLSLKEIKKLLKRL------------NIRVSEKELKKLFKEVDTNGDGTLTFDEFEE 60

EF hand;

                          10        20
                  ....*....|....*....|..
gi 19913441   150 DKIFRQMDTNNDGKLSLEEFIR 171
Cdd:pfam13202   2 KDTFRQIDLNGDGKISKEELRR 23

EF hand; The EF-hands can be divided into two classes: signalling proteins and buffering/transport proteins. The first group is the largest and includes the most well-known members of the family such as calmodulin, troponin C and S100B. These proteins typically undergo a calcium-dependent conformational change which opens a target binding site. The latter group is represented by calbindin D9k and do not undergo calcium dependent conformational changes.

                          10        20
                  ....*....|....*....|...
gi 19913441    68 VFRTFDTNGDGTIDFREFIIALS 90
Cdd:pfam00036   5 IFRLFDKDGDGKIDFEEFKELLK 27

EF-hand, calcium binding motif, found in uncharacterized calglandulin-like proteins; The family corresponds to a group of uncharacterized calglandulin-like proteins. Although their biological function remain unclear, they show high sequence similarity with human calglandulin-like protein GAGLP, which is an ortholog of calglandulin from the venom glands of Bothrops insularis snake. Both GAGLP and calglandulin are putative Ca2+-binding proteins with four EF-hand motifs. However, members in this family contain only three EF-hand motifs. In this point, they may belong to the parvalbumin-like EF-hand family, which is characterized by the presence of three consecutive EF-hand motifs (helix-loop-helix).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  91 VTSRGKLEQKLKWAFSMYDLDGNGYISRSEMLEIVQAIykmVSSVMKMP-EDEstpekRTDKIFRQMDTNNDGKLSLEEF 169
Cdd:cd16252  29 FQTSEQQEEAIRKAFQMLDKDKSGFIEWNEIKYILSTV---PSSMPVAPlSDE-----EAEAMIQAADTDGDGRIDFQEF 100

EF-hand, calcium binding motif, found in calretinin (CR); CR, also termed 29 kDa calbindin, is a cytosolic hexa-EF-hand calcium-binding protein predominantly expressed in a variety of normal and tumorigenic t specific neurons of the central and peripheral nervous system. It possibly functions as a calcium buffer, calcium sensor, and apoptosis regulator, which may be implicated in many biological processes, including cell proliferation, differentiation, and cell death. CR contains six EF-hand motifs within two independent domains, CR I-II and CR III-VI. CR I-II consists of EF-hand motifs 1 and 2, and CR III-VI consists of EF-hand motifs 3-6. The first 5 EF-hand motifs are capable of binding calcium ions, while the EF-hand 6 is inactive. Thus, CR has two pairs of cooperative binding sites (I-II and III-IV), which display high affinity calcium-binding sites, and one independent calcium ion-binding site (V), which displays lower affinity binding.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  40 TGHLTVDEFKKIYANFF-----PYGDAS--KFAEHVFRTFDTNGDGTIDFREFIIALSVTSRGKLE-QKLKWA------- 104
Cdd:cd16177 104 SGYIEANELKGFLSDLLkkanrPYDEKKlqEYTQTILRMFDLNGDGKLGLSEMARLLPVQENFLLKfQGMKLSseefnai 183

                        90       100
                ....*....|....*....|....*.
gi 19913441 105 FSMYDLDGNGYISRSEMLEIVQAIYK 130
Cdd:cd16177 184 FAFYDKDGSGYIDENELDALLKDLYE 209

Calgranulins: S-100 domain found in proteins belonging to the Calgranulin subgroup of the S100 family of EF-hand calcium-modulated proteins, including S100A8, S100A9, and S100A12 . Note that the S-100 hierarchy, to which this Calgranulin group belongs, contains only S-100 EF-hand domains, other EF-hands have been modeled separately. These proteins are expressed mainly in granulocytes, and are involved in inflammation, allergy, and neuritogenesis, as well as in host-parasite response. Calgranulins are modulated not only by calcium, but also by other metals such as zinc and copper. Structural data suggested that calgranulins may exist in multiple structural forms, homodimers, as well as hetero-oligomers. For example, the S100A8/S100A9 complex called calprotectin plays important roles in the regulation of inflammatory processes, wound repair, and regulating zinc-dependent enzymes as well as microbial growth.

                        10        20
                ....*....|....*....|....*
gi 19913441 146 EKRTDKIFRQMDTNNDGKLSLEEFI 170
Cdd:cd05030  50 QKAIDKIFEDLDTNQDGQLSFEEFL 74

EF-hand, calcium binding motif, found in calumenin, reticulocalbin-1 (RCN-1), reticulocalbin-3 (RCN-3), and similar proteins; The family corresponds to a group of six EF-hand Ca2+-binding proteins, including calumenin (also known as crocalbin or CBP-50), reticulocalbin-1 (RCN-1), reticulocalbin-3 (RCN-3), and similar proteins. Calumenin is an endo/sarcoplasmic reticulum (ER/SR) resident low-affinity Ca2+-binding protein that contains six EF-hand domains and a C-terminal SR retention signal His-Asp-Glu-Phe (HDEF) tetrapeptide. It functions as a novel regulator of SERCA2, and its expressional changes are tightly coupled with Ca2+-cycling of cardiomyocytes. It is also broadly involved in haemostasis and in the pathophysiology of thrombosis. Moreover, the extracellular calumenin acts as a suppressor of cell migration and tumor metastasis. RCN-1 is an endoplasmic reticulum resident Ca2+-binding protein with a carboxyl-terminal His-Asp-Glu-Leu (HDEL) tetrapeptide signal. It acts as a potential negative regulator of B-RAF activation and can negatively modulate cardiomyocyte hypertrophy by inhibition of the mitogen-activated protein kinase signalling cascade. It also plays a key role in the development of doxorubicin-associated resistance. RCN-3 is a putative six EF-hand Ca2+-binding protein that contains five RXXR (X is any amino acid) motifs and a C-terminal ER retrieval signal HDEL tetrapeptide. The RXXR motif represents the target sequence of subtilisin-like proprotein convertases (SPCs). RCN-3 is specifically bound to the paired basic amino-acid-cleaving enzyme-4 (PACE4) precursor protein and plays an important role in the biosynthesis of PACE4.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  68 VFRTFDTNGDGTIDFREFIIALSVTSRGKLEQKLKWAFSMYDLDGNGYISRSEMLEIVQAIYKMVSSVMKMPEDESTPEK 147
Cdd:cd16226  40 IVDKIDKNGDGFVTEEELKDWIKYVQKKYIREDVDRQWKEYDPNKDGKLSWEEYKKATYGFLDDEEEDDDLHESYKKMIR 119

                        90       100
                ....*....|....*....|..
gi 19913441 148 RTDKIFRQMDTNNDGKLSLEEF 169
Cdd:cd16226 120 RDERRWKAADQDGDGKLTKEEF 141

EF hand;

                          10        20
                  ....*....|....*....|
gi 19913441    66 EHVFRTFDTNGDGTIDFREF 85
Cdd:pfam13202   2 KDTFRQIDLNGDGKISKEEL 21

EF-hand, calcium binding motif, found in apoptosis-linked gene 2 protein (ALG-2) and similar proteins; ALG-2, also termed programmed cell death protein 6 (PDCD6), or probable calcium-binding protein ALG-2, is one of the prototypic members of the penta EF-hand protein family. It is a widely expressed calcium-binding modulator protein associated with cell proliferation and death, as well as cell survival. ALG-2 acts as a pro-apoptotic factor participating in T cell receptor-, Fas-, and glucocorticoid-induced programmed cell death, and also serves as a useful molecular marker for the prognosis of cancers. Moreover, ALG-2 functions as a calcium ion sensor at endoplasmic reticulum (ER) exit sites, and modulates ER-stress-stimulated cell death and neuronal apoptosis during organ formation. Furthermore, ALG-2 can mediate the pro-apoptotic activity of cisplatin or tumor necrosis factor alpha (TNFalpha) through the down-regulation of nuclear factor-kappaB (NF-kappaB) expression. It also inhibits angiogenesis through PI3K/mTOR/p70S6K pathway by interacting of vascular endothelial growth factor receptor-2 (VEGFR-2). In addition, nuclear ALG-2 may participate in the post-transcriptional regulation of Inositol Trisphosphate Receptor Type 1 (IP3R1) pre-mRNA at least in part by interacting with CHERP (Ca2+ homeostasis endoplasmic reticulum protein) calcium-dependently. ALG-2 contains five serially repeated EF-hand motifs and interacts with various proteins, including ALG-2-interacting protein X (Alix), Fas, annexin XI, death-associated protein kinase 1 (DAPk1), Tumor susceptibility gene 101 (TSG101), Sec31A, phospholipid scramblase 3 (PLSCR3), the P-body component PATL1, and endosomal sorting complex required for transport (ESCRT)-III-related protein IST1, in a calcium-dependent manner. It forms a homodimer in the cell or a heterodimer with its closest paralog peflin. Among the PEF proteins, ALG-2 can bind three Ca2+ ions through its EF1, EF3, and EF5 hands, where it is unique in that its EF5 hand binds Ca2+ ion in a canonical coordination.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 19913441  56 FPYGDASKFAEHVFRTFDTNGDGTIDFREFIIALSVTsrgkleQKLKWAFSMYDLDGNGYISRS--EMLEIV 125
Cdd:cd16183  96 FGYRLSDQFYDILVRKFDRQGRGTIAFDDFIQCCVVL------QTLTDSFRRYDTDQDGWIQISyeQFLEMV 161

EF-hand, calcium binding motif, found in Drosophila melanogaster calbindin-32 (CBN) and similar proteins; CBN, the product of the cbn gene, is a Drosophila homolog to vertebrate neuronal six EF-hand calcium binding proteins. It is expressed through most of ontogenesis with a selective distribution in the nervous system and in a few small adult thoracic muscles. Its precise biological role remains unclear. CBN contains six EF-hand motifs, but some of them may not bind calcium ions due to the lack of key residues.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19913441  60 DASKFAEHVFRTFDTNGDGTIDFRE----------FIIALSVTSrgKLEQKLKW--AFSMYDLDGNGYISRSEMLEIVQA 127
Cdd:cd16179  46 ALEELKEEFMEAYDENQDGRIDIRElaqllpteenFLLLFRRDN--PLDSSVEFmkVWREYDKDNSGYIEADELKNFLKH 123

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*..
gi 19913441 128 IYKMvssvmKMPEDESTPEK---RTDKIFRQMDTNNDGKLSLEEFIR 171
Cdd:cd16179 124 LLKE-----AKRDNDVSEDKlieYTDTILQLFDRNKDGKLQLSEMAR 165