basic Helix Loop Helix (bHLH) domain superfamily; bHLH proteins are transcriptional regulators that are found in organisms from yeast to humans. Members of the bHLH superfamily have two highly conserved and functionally distinct regions. The basic part is at the amino end of the bHLH that may bind DNA to a consensus hexanucleotide sequence known as the E box (CANNTG). Different families of bHLH proteins recognize different E-box consensus sequences. At the carboxyl-terminal end of the region is the HLH region that interacts with other proteins to form homo- and heterodimers. bHLH proteins function as a diverse set of regulatory factors because they recognize different DNA sequences and dimerize with different proteins. The bHLH proteins can be divided to cell-type specific and widely expressed proteins. The cell-type specific members of bHLH superfamily are involved in cell-fate determination and act in neurogenesis, cardiogenesis, myogenesis, and hematopoiesis.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 802628577 201 VRARRGQATDPHSIAERLRREKIAERMKNLQELVPNSTKI-DKASMLDEIIEYVKFLQLQVKVLSMsRLGAAGAVI 275
Cdd:cd18919    5 VRARRGQATDSHSLAERVRREKISERMKLLQDLVPGCNKVtGKALMLDEIINYVQSLQRQVEFLSM-KLAAVNPRL 79

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana BIG PETAL (BPE) and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as BPE, HBI1 and BEE proteins (BEE1-3). BPE, also termed AtbHLH31, or EN 88, is involved in the control of Arabidopsis petal size, by interfering with postmitotic cell expansion to limit final petal cell size. HBI1, also termed AtbHLH64, or homolog of bee2 interacting with IBH1, or EN 79, is an atypical bHLH transcription factor that acts as positive regulator of cell elongation downstream of multiple external and endogenous signals by direct binding to the promoters and activation of the two expansin genes EXPA1 and EXPA8, encoding cell wall loosening enzymes. BEEs, also termed protein Brassinosteroid enhanced expression, are positive regulators of brassinosteroid signaling.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 802628577 201 VRARRGQATDPHSIAERLRREKIAERMKNLQELVPNSTKI-DKASMLDEIIEYVKFLQLQVKVLSMsRLGAAGAVI 275
Cdd:cd18919    5 VRARRGQATDSHSLAERVRREKISERMKLLQDLVPGCNKVtGKALMLDEIINYVQSLQRQVEFLSM-KLAAVNPRL 79

Helix-loop-helix DNA-binding domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 802628577  212 HSIAERLRREKIAERMKNLQELVP---NSTKIDKASMLDEIIEYVKFLQ 257
Cdd:pfam00010   5 HNERERRRRDRINDAFDELRELLPtlpPDKKLSKAEILRLAIEYIKHLQ 53

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana BIG PETAL (BPE) and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as BPE, HBI1 and BEE proteins (BEE1-3). BPE, also termed AtbHLH31, or EN 88, is involved in the control of Arabidopsis petal size, by interfering with postmitotic cell expansion to limit final petal cell size. HBI1, also termed AtbHLH64, or homolog of bee2 interacting with IBH1, or EN 79, is an atypical bHLH transcription factor that acts as positive regulator of cell elongation downstream of multiple external and endogenous signals by direct binding to the promoters and activation of the two expansin genes EXPA1 and EXPA8, encoding cell wall loosening enzymes. BEEs, also termed protein Brassinosteroid enhanced expression, are positive regulators of brassinosteroid signaling.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 802628577 201 VRARRGQATDPHSIAERLRREKIAERMKNLQELVPNSTKI-DKASMLDEIIEYVKFLQLQVKVLSMsRLGAAGAVI 275
Cdd:cd18919    5 VRARRGQATDSHSLAERVRREKISERMKLLQDLVPGCNKVtGKALMLDEIINYVQSLQRQVEFLSM-KLAAVNPRL 79

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein INDEHISCENT (IND) and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as IND, HEC proteins (HEC1, HEC2 and HEC3) and UNE12. IND, also termed AtbHLH40, or EN 120, is a bHLH transcription regulator required for seed dispersal. It is involved in the differentiation of all three cell types required for fruit dehiscence. HEC1 (also termed AtbHLH88, or protein HECATE 1, or EN 118), HEC2 (also termed AtbHLH37, or protein HECATE 2, or EN 117) and HEC3 (also termed AtbHLH43, or protein HECATE 3, or EN 119) are required for the female reproductive tract development and fertility. Both IND and HEC proteins have been implicated in regulation of auxin signaling. They heterodimerize with SPATULA (SPT) bHLH transcription factor to regulate reproductive tract development in plant. UNE12, also termed AtbHLH59, or protein UNFERTILIZED EMBRYO SAC 12, or EN 93, is required for ovule fertilization.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 802628577 208 ATDPHSIAERLRREKIAERMKNLQELVPNSTKIDKASMLDEIIEYVKFLQLQVKVLSMSRL 268
Cdd:cd11454    1 STDPQSVAARHRRERISERIRILQRLVPGGTKMDTASMLDEAIHYVKFLQLQVKLLQSDDL 61

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana BES1-interacting Myc-like proteins (BIMs) and similar proteins; The family includes Arabidopsis thaliana BIM1 and its homologs (BIM2 and BIM3), which are bHLH transcription factors that interact with BES1 to regulate transcription of Brassinosteroid (BR)-induced gene. BR regulates many growth and developmental processes such as cell elongation, vascular development, senescence stress responses, and photomorphogenesis. BIM1 heterodimerize with BES1 and bind to E-box sequences present in many BR-induced promoters to regulated BR-induced genes.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 802628577 212 HSIAERLRREKIAERMKNLQELVPNST-KIDKASMLDEIIEYVKFLQLQVKVLSMSRLGAAGAVIPLI 278
Cdd:cd11453    7 HSATEQRRRSKINERLQALRDLIPHSDqKRDKASFLLEVIEYIQALQEKVAKLEEQVQGWGGEPAKLT 74

helix loop helix domain;

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|..
gi 802628577   213 SIAERLRREKIAERMKNLQELVP---NSTKIDKASMLDEIIEYVKFLQLQVK 261
Cdd:smart00353   1 NARERRRRRKINEAFDELRSLLPtlpKNKKLSKAEILRLAIEYIKSLQEELQ 52

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein AIG1 and similar proteins; AIG1, also termed AtbHLH32, or EN 54, or protein target of MOOPTEROS 5, is a transcription factor required for MONOPTEROS-dependent root initiation in embryo.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 802628577 203 ARRGQATDPHSIAERLRREKIAERMKNLQELVPNSTKIDKASMLDEIIEYVKFLQLQVKVLS 264
Cdd:cd11455    2 DKALAASKSHSEAERRRRERINSHLATLRTLLPNLSKTDKASLLAEVVQHVKELKRQAAEIT 63

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein ABA-INDUCIBLE bHLH-TYPE (AIB) and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as AIB and MYC proteins (MYC2, MYC3 and MYC4). AIB, also termed AtbHLH17, or EN 35, is a transcription activator that regulates positively abscisic acid (ABA) response. MYC2, also termed protein jasmonate insensitive 1, or R-homologous Arabidopsis protein 1 (RAP-1), or AtbHLH6, or EN 38, or Z-box binding factor 1 protein, is a transcriptional activator involved in abscisic acid (ABA), jasmonic acid (JA), and light signaling pathways. MYC3, also termed protein altered tryptophan regulation 2, or AtbHLH5, or transcription factor ATR2, or EN 36, is a transcription factor involved in tryptophan, jasmonic acid (JA) and other stress-responsive gene regulation. MYC4, also termed AtbHLH4, or EN 37, is a transcription factor involved in jasmonic acid (JA) gene regulation. MYC2, together with MYC3 and MYC4, controls additively subsets of JA-dependent responses.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 802628577 212 HSIAERLRREKIAERMKNLQELVPNSTKIDKASMLDEIIEYVKFLQLQVKVLSMSR 267
Cdd:cd11449    9 HVEAERQRREKLNQRFYALRAVVPNVSKMDKASLLGDAISYINELKSKVQDMETEK 64

basic Helix-Loop-Helix (bHLH) domain found in Arabidopsis thaliana MYC1 and similar proteins; MYC1, also termed AtbHLH12, or EN 58, acts as a transcription activator, when associated with MYB75/PAP1 or MYB90/PAP2.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 802628577 216 ERLRREKIAERMKNLQELVPNSTKIDKASMLDEIIEYVKFLQLQVKVLSM 265
Cdd:cd18918    5 ERERREKLNEKFSDLRNLIPNPTKNDRASILSDAIKYINELQRTVEELKS 54

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein aborted microspores (AMS) and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as AMS, ICE1 and SCREAM2. AMS, also termed AtbHLH21, or EN 48, plays a crucial role in tapetum development and it is required for male fertility and pollen differentiation. ICE1, also termed inducer of CBF expression 1, or AtbHLH116, or EN 45, or SCREAM, acts as a transcriptional activator that regulates the cold-induced transcription of CBF/DREB1 genes. It binds specifically to the MYC recognition sites (5'-CANNTG-3') found in the CBF3/DREB1A promoter. SCREAM2, also termed AtbHLH33, or EN 44, mediates stomatal differentiation in the epidermis probably by controlling successive roles of SPCH, MUTE, and FAMA.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 802628577 215 AERLRREKIAERMKNLQELVPNSTKIDKASMLDEIIEYVKFLQLQVKVL 263
Cdd:cd11443    6 AERRRRKKLNDRLYMLRSVVPKITKMDRASILGDAIDYVKELLQEINEL 54

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana ILI1-BINDING BHLH 1 (IBH1) and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as IBH1, UPBEAT1, PAR1 and PAR2. IBH1, also termed bHLH zeta, or AtbHLH158, is an atypical and probable non DNA-binding bHLH transcription factor that acts as transcriptional repressor that negatively regulates cell and organ elongation in response to gibberellin (GA) and brassinosteroid (BR) signaling. IBH1 forms heterodimer with BHLH49, thus inhibiting DNA binding of BHLH49, which is a transcriptional activator that regulates the expression of a subset of genes involved in cell expansion by binding to the G-box motif. UPBEAT1, also termed AtbHLH151, or EN 146, is a bHLH transcription factor that modulates the balance between cellular proliferation and differentiation in root growth. It does not act through cytokinin and auxin signaling, but by repressing peroxidase expression in the elongation zone. PAR1 (also termed AtbHLH165, or protein helix-loop-helix 1, or protein phytochrome rapidly regulated 1) and PAR2 (also termed AtbHLH166, or protein helix-loop-helix 2, or protein phytochrome rapidly regulated 2) are two atypical bHLH transcription factors that act as negative regulators of a variety of shade avoidance syndrome (SAS) responses, including seedling elongation and photosynthetic pigment accumulation. They act as direct transcriptional repressor of two auxin-responsive genes, SAUR15 and SAUR68. They may function in integrating shade and hormone transcriptional networks in response to light and auxin changes.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 802628577 215 AERLRREKIAERMKNLQELVPN-STKIDKASMLDEIIEYVKFLQLQVKVLSM 265
Cdd:cd11444    4 RRRRGEEAIERRLRALRRLVPGgRESMEVEELLQETADYIMFLEMQVKVMKS 55

basic helix-loop-helix (bHLH) domain found in the spermatogenesis- and oogenesis-specific basic helix-loop-helix-containing protein (SOHLH) family and similar proteins; The SOHLH family includes two bHLH transcription factors, SOHLH1 and SOHLH2. They are specifically in spermatogonia and oocytes and essential for early spermatogonial and oocyte differentiation. The family also includes transcription factor-like 5 protein (TCFL5) and similar proteins. TCFL5, also termed Cha transcription factor, or HPV-16 E2-binding protein 1 (E2BP-1), is a bHLH transcription factor that plays a crucial role in spermatogenesis. It regulates cell proliferation or differentiation of cells through binding to a specific DNA sequence like other bHLH molecules.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 802628577 207 QATDPHSIAERLRREKIAERMKNLQELVP-NSTKIDKASMLDEIIEYVKFLQ 257
Cdd:cd19683    1 KSRERHNAKERQRRERIKIACDQLRKLVPgCSRKTDKATVFEFTVAYIKFLR 52

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in the microphthalmia-associated transcription factor family (MITF) family; The MITF (also known as microphthalmia-TFE, or MiT) family is a small family that contain a basic helix loop helix domain associated with a leucine zipper (bHLHZip). The MITF family comprises four genes in mammals (MITF, TFE3, TFEB, and TFEC); each gene has different functions. MITF is involved in neural crest melanocytes development as well as the pigmented retinal epithelium. TFEB is required for vascularization of the mouse placenta. TFE3 is involved in B cell function. TFEC regulates gene expression in macrophages. The MITF family can form homodimers or heterodimers with each other but not with other bHLH or bHLHzip proteins.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 802628577 207 QATDPHSIAERLRREKIAERMKNLQELVPNST----KIDKASMLDEIIEYVKFLQ 257
Cdd:cd11397    4 QKKDNHNMIERRRRFNINDRIKELGTLLPKSNdpdmRWNKGTILKASVDYIRKLQ 58

basic helix-loop-helix-orange (bHLH-O) domain found in hairy and enhancer of split (HES)-related repressor protein (HERP)-like family; The HERP-like family includes bHLH-O transcriptional regulators that are related to the Drosophila hairy and Enhancer-of-split proteins. They contain a basic helix-loop-helix (bHLH) domain with an invariant glycine residue in its basic region, an orange domain in the central region and YXXW sequence motif at its C-terminal region. HERP proteins (HEY1, HEY2 and HEYL) act as downstream effectors of Notch signaling. They are involved in cardiovascular development and have roles in somitogenesis, myogenesis and gliogenesis. Hairy and enhancer of split-related protein HELT is a transcriptional repressor expressed in the developing central nervous system. It binds preferentially to the canonical E box sequence 5'-CACGCG-3' and regulates neuronal differentiation and/or identity. Differentially expressed in chondrocytes proteins, DEC1 and DEC2, are widely expressed in both embryonic and adult tissues and have been implicated in apoptosis, cell proliferation, and circadian rhythms, as well as malignancy in various cancers. Drosophila melanogaster protein clockwork orange (Cwo) is also included in this family. It is involved in the regulation of Drosophila circadian rhythms. It functions as both an activator and a repressor of clock gene expression.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 802628577 212 HSIAERLRREKIAERMKNLQELVPN------STKIDKASMLDEIIEYVKFLQ 257
Cdd:cd11389    1 HKVIEKRRRDRINESLAELRRLVPEarkskgSGKLEKAEILEMTLQHLKALQ 52

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in transcription factor EC (TFEC) and similar proteins; TFEC, also termed Class E basic helix-loop-helix protein 34 (bHLHe34), or transcription factor EC-like (TFEC-L), is a bHLHzip transcriptional regulator that acts as a repressor or an activator and regulates gene expression in macrophages. It plays an important role in the niche to expand hematopoietic progenitors through the modulation of several cytokines.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 802628577 207 QATDPHSIAERLRREKIAERMKNLQELVPNSTKID----KASMLDEIIEYVKFLQ 257
Cdd:cd18925    4 QKKDNHNLIERRRRYNINYRIKELGTLIPKSNDPDmrwnKGTILKASVEYIKWLQ 58

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in microphthalmia-associated transcription factor (MITF) and similar proteins; MITF, also termed Class E basic helix-loop-helix protein 32 (bHLHe32), is a bHLHzip transcription factor that is involved in neural crest melanocytes development as well as the pigmented retinal epithelium. It regulates the expression of genes with essential roles in cell differentiation, proliferation and survival. It binds to M-boxes (5'-TCATGTG-3') and symmetrical DNA sequences (E-boxes) (5'-CACGTG-3') found in the promoters of target genes, such as BCL2 and tyrosinase (TYR).

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 802628577 200 RVRARRGQATDPHSIAERLRREKIAERMKNLQELVPNSTKID----KASMLDEIIEYVKFLQ 257
Cdd:cd18926    5 RALAKERQKKDNHNLIERRRRFNINDRIKELGTLIPKSNDPDmrwnKGTILKASVDYIRKLQ 66

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in sterol regulatory element-binding protein 2 (SREBP2) and similar proteins; SREBP2, also termed Class D basic helix-loop-helix protein 2 (bHLHd2), or sterol regulatory element-binding transcription factor 2 (SREBF2), is a member of a family of bHLHzip transcription factors that recognize sterol regulatory element 1 (SRE-1). It acts as a transcription activator of cholesterol biosynthesis.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 802628577 204 RRGQATDPHSIAERLRREKIAERMKNLQELV-PNSTKIDKASMLDEIIEYVKFLQ 257
Cdd:cd18922    2 KEGERRTTHNIIEKRYRSSINDKIIELKDLVmGTDAKMHKSGVLRKAIDYIKYLQ 56

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein LONESOME HIGHWAY (LHW) and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as LHW, and EMB1444. LHW, also termed AtbHLH156, or bHLH delta, is a bHLH transcription activator that regulates root development and promotes the production of stele cells in roots. It coordinately controls the number of all vascular cell types by regulating the size of the pool of cells from which they arise. EMB1444, also termed AtbHLH169, or lonesome highway-like protein 1, or protein embryo defective 1444, may regulate root development.

                         10        20        30
                 ....*....|....*....|....*....|....*...
gi 802628577 220 REKIAERMKNLQELVPNSTKIDKASMLDEIIEYVKFLQ 257
Cdd:cd18915   10 RQMIQDRIKELREIVPNGAKCSIDALLERTIKHMLFLQ 47

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein IAA-leucine resistant 3 (ILR3) and similar proteins; ILR3, also termed AtbHLH105, or EN 133, is a bHLH transcription factor that plays a role in resistance to amide-linked indole-3-acetic acid (IAA) conjugates such as IAA-Leu and IAA-Phe. It may regulate gene expression in response to metal homeostasis changes.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 802628577 216 ERLRREKIAERMKNLQELV-PNST-KIDKASMLDEIIEYVKFLQLQVKVL 263
Cdd:cd11446    5 EKLRRDKLNERFMELSNVLePGRPpKTDKATILGDAIRMLKQLRGEVQKL 54

basic helix-loop-helix-orange (bHLH-O) domain found in hairy and enhancer of split (HES)-related repressor protein (HERP) family; HERP (also called Hey/Hesr/HRT/CHF/gridlock) proteins corresponds to a family of bHLH-O transcriptional repressors that are related to the Drosophila hairy and Enhancer-of-split proteins and act as downstream effectors of Notch signaling. They contain a basic helix-loop-helix (bHLH) domain with an invariant glycine residue in its basic region, an orange domain in the central region and YXXW sequence motif at its C-terminal region. HERP proteins are involved in cardiovascular development and have roles in somitogenesis, myogenesis and gliogenesis.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 802628577 201 VRARRGqatdphsIAERLRREKIAERMKNLQELVPN------STKIDKASMLDEIIEYVKFLQ 257
Cdd:cd11407    1 RKKRRG-------IIEKRRRDRINNSLAELRRLVPTafekqgSAKLEKAEILQMTVDHLKMLH 56

basic helix-loop-helix-orange (bHLH-O) domain found in HERP/HES-like family; The HERP/HES-like family includes bHLH-O transcriptional regulators that are related to the Drosophila hairy and Enhancer-of-split (HES) proteins. The HERP (HES-related repressor protein) subfamily proteins contain a basic helix-loop-helix (bHLH) domain with an invariant glycine residue in its basic region, an orange domain in the central region and YXXW sequence motif at its C-terminal region. Hairy and enhancer of split (HES)-related repressor protein (HERP) proteins (HEY1, HEY2 and HEYL) act as downstream effectors of Notch signaling. They are involved in cardiovascular development and have roles in somitogenesis, myogenesis and gliogenesis. Hairy and enhancer of split-related protein HELT is a transcriptional repressor expressed in the developing central nervous system. It binds preferentially to the canonical E box sequence 5'-CACGCG-3' and regulates neuronal differentiation and/or identity. Differentially expressed in chondrocytes proteins, DEC1 and DEC2, are widely expressed in both embryonic and adult tissues and have been implicated in apoptosis, cell proliferation, and circadian rhythms, as well as malignancy in various cancers. Drosophila melanogaster protein clockwork orange (Cwo) is also included in this subfamily. It is involved in the regulation of Drosophila circadian rhythms. It functions as both an activator and a repressor of clock gene expression. The HES subfamily proteins contain a basic helix-loop-helix (bHLH) domain with an invariant proline residue in its basic region, an orange domain in the central region and a conserved tetrapeptide motif, WRPW, at its C-terminal region. They form heterodimers or homodimers via their HLH domain and bind DNA to repress gene transcription that play an essential role in development of both compartment and boundary cells of the central nervous system.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 802628577 216 ERLRREKIAERMKNLQELVPNS------TKIDKASMLDEIIEYVKFLQLQV 260
Cdd:cd19685    2 EKRRRQRINDKLNQLKELLPPNlskqsrSKLSKAEILEMAITELRRLQQEV 52

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in sterol regulatory element-binding protein 1 (SREBP1) and similar proteins; SREBP1, also termed Class D basic helix-loop-helix protein 1 (bHLHd1), or sterol regulatory element-binding transcription factor 1 (SREBF1), is a member of a family of bHLHzip transcription factors that recognize sterol regulatory element 1 (SRE-1). It acts as a transcriptional activator required for lipid homeostasis. It may control transcription of the low-density lipoprotein receptor gene as well as the fatty acid. SREBP1 has dual sequence specificity binding to both an E-box motif (5'-ATCACGTGA-3') and to SRE-1 (5'-ATCACCCCAC-3').

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 802628577 205 RGQATDPHSIAERLRREKIAERMKNLQELVP-NSTKIDKASMLDEIIEYVKFLQLQVKVL 263
Cdd:cd18921    3 KGEKRTAHNAIEKRYRSSINDKIIELKDLVVgTEAKLNKSAVLRKAIDYIRFLQQSNQKL 62

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in Schizosaccharomyces pombe ESC1 (spESC1) and similar proteins; spESC1 is a bHLHzip protein with homology to human MyoD and Myf-5 myogenic differentiation inducers. It is involved in the sexual differentiation process.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 802628577 212 HSIAERLRREKIAERMKNLQELVPN--STKIDKASMLDEIIEYVKFLQLQVKVL 263
Cdd:cd19690    4 HKLAERKRRKEMKELFEDLRDALPQerGTKASKWEILTKAISYIQQLKRHIREL 57

basic helix-loop-helix-orange (bHLH-O) domain found in differentially expressed in chondrocytes protein 1 (DEC1) and similar proteins; DEC1, also termed Class E basic helix-loop-helix protein 40 (bHLHe40), or Class B basic helix-loop-helix protein 2 (bHLHb2), or enhancer-of-split and hairy-related protein 2 (SHARP-2), or stimulated by retinoic acid gene 13 protein (STRA13), is a bHLH-O transcriptional repressor involved in the regulation of the circadian rhythm by negatively regulating the activity of the clock genes and clock-controlled genes.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 802628577 211 PHSIAERLRREKIAERMKNLQELVPNSTK------IDKASMLDEIIEYVKFL-----QLQVKVLSM 265
Cdd:cd19749   17 PHRLIEKKRRDRINECIAQLKDLLPEHLKlttlghLEKAVVLELTLKHVKALtslieQQQQKILAL 82

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in MLX-interacting protein (MLXIP), MLX-interacting protein-like (MLXIPL) and similar proteins; The family includes MLXIP and MLXIPL. MLXIP, also termed Class E basic helix-loop-helix protein 36 (bHLHe36), or transcriptional activator MondoA, is a bHLHZip transcriptional activator that binds DNA as a heterodimer with Mlx. It binds to the canonical E box sequence 5'-CACGTG-3' and plays a role in transcriptional activation of glycolytic target genes. MLXIP is most highly expressed in skeletal muscle and functions as an indirect glucose sensor, by sensing glucose 6-phosphate and shuttling between the nucleus and the cytoplasm. MLXIPL, also termed carbohydrate-responsive element-binding protein (ChREBP), or Class D basic helix-loop-helix protein 14 (bHLHd14), or MLX interactor, or WS basic-helix-loop-helix leucine zipper protein (WS-bHLH), or Williams-Beuren syndrome chromosomal region 14 protein (WBSCR14), is a bHLHZip transcriptional factor integral to the regulation of glycolysis and lipogenesis in the liver. It forms heterodimers with the bHLHZip protein Mlx to bind the DNA sequence 5'-CACGTG-3'.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 802628577 212 HSIAERLRREKIAERMKNLQELVPNST-----KIDKASMLDEIIEYVKFLQ 257
Cdd:cd11405    7 HISAEQKRRFNIKSGFDTLQSLIPSLGqnpnqKVSKAAMLQKAAEYIKSLK 57