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        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 357488103  43 SVIRSKHSVTEQRRRSKINERFQILRDLIPQCDQKRDTASFLLEVIEYVQYLQERVQKYEGSYQGWSQEPSKLMPWR 119
Cdd:cd11453    1 STPRSKHSATEQRRRSKINERLQALRDLIPHSDQKRDKASFLLEVIEYIQALQEKVAKLEEQVQGWGGEPAKLTPWA 77

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        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 357488103  43 SVIRSKHSVTEQRRRSKINERFQILRDLIPQCDQKRDTASFLLEVIEYVQYLQERVQKYEGSYQGWSQEPSKLMPWR 119
Cdd:cd11453    1 STPRSKHSATEQRRRSKINERLQALRDLIPHSDQKRDKASFLLEVIEYIQALQEKVAKLEEQVQGWGGEPAKLTPWA 77

Helix-loop-helix DNA-binding domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 357488103   46 RSKHSVTEQRRRSKINERFQILRDLIP--QCDQKRDTASFLLEVIEYVQYLQ 95
Cdd:pfam00010   2 REAHNERERRRRDRINDAFDELRELLPtlPPDKKLSKAEILRLAIEYIKHLQ 53

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        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 357488103  43 SVIRSKHSVTEQRRRSKINERFQILRDLIPQCDQKRDTASFLLEVIEYVQYLQERVQKYEGSYQGWSQEPSKLMPWR 119
Cdd:cd11453    1 STPRSKHSATEQRRRSKINERLQALRDLIPHSDQKRDKASFLLEVIEYIQALQEKVAKLEEQVQGWGGEPAKLTPWA 77

helix loop helix domain;

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|
gi 357488103    53 EQRRRSKINERFQILRDLIPQC--DQKRDTASFLLEVIEYVQYLQERVQK 100
Cdd:smart00353   4 ERRRRRKINEAFDELRSLLPTLpkNKKLSKAEILRLAIEYIKSLQEELQK 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 357488103  36 GKATDKasvirskHSVTEQRRRSKINERFQILRDLIPQCDQKRDTASFLLEVIEYVQYLQERVQ 99
Cdd:cd18919   10 GQATDS-------HSLAERVRREKISERMKLLQDLVPGCNKVTGKALMLDEIINYVQSLQRQVE 66

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana phytochrome interacting factors (PIFs) and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as PIFs, ALC, PIL1, SPATULA, and UNE10. PIFs (PIF1, PIF3, PIF4, PIF5, PIF6 and PIF7) have been shown to control light-regulated gene expression. They directly bind to the photoactivated phytochromes and are degraded in response to light signals. ALC, also termed AtbHLH73, or protein ALCATRAZ, or EN 98, is required for the dehiscence of fruit, especially for the separation of the valve cells from the replum. It promotes the differentiation of a strip of labile non-lignified cells sandwiched between layers of lignified cells. PIL1, also termed AtbHLH124, or protein phytochrome interacting factor 3-like 1, or EN 110, is involved in responses to transient and long-term shade. It is required for the light-mediated inhibition of hypocotyl elongation and necessary for rapid light-induced expression of the photomorphogenesis- and circadian-related gene APRR9. PIL1 seems to play a role in multiple PHYB responses, such as flowering transition and petiole elongation. SPATULA, also termed AtbHLH24, or EN 99, plays a role in floral organogenesis. It promotes the growth of carpel margins and of pollen tract tissues derived from them. UNE10, also termed AtbHLH16, or protein UNFERTILIZED EMBRYO SAC 10, or EN 99, is required during the fertilization of ovules by pollen.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 357488103  49 HSVTEQRRRSKINERFQILRDLIPQCDqKRDTASFLLEVIEYVQYLQERVQ 99
Cdd:cd11445    6 HNLSERRRRDRINEKMKALQELIPNCN-KTDKASMLDEAIEYLKSLQLQVQ 55

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 357488103  49 HSVTEQRRRSKINERFQILRDLIPQcDQKRDTASFLLEVIEYVQYLQERVQKYE 102
Cdd:cd18918    1 LFATERERREKLNEKFSDLRNLIPN-PTKNDRASILSDAIKYINELQRTVEELK 53

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
                 ....*....|....*....|....*....|....*....|....*....|
gi 357488103  50 SVTEQRRRSKINERFQILRDLIPQcDQKRDTASFLLEVIEYVQYLQERVQ 99
Cdd:cd11454    6 SVAARHRRERISERIRILQRLVPG-GTKMDTASMLDEAIHYVKFLQLQVK 54

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in sterol regulatory element-binding protein (SREBP) family and similar proteins; The SREBP family includes SREBP1 and SREBP2, which are bHLHzip transcriptional activator of genes encoding proteins essential for cholesterol biosynthesis/uptake and fatty acid biosynthesis. SREBP1 and SREBP2 are principally found in the liver and in adipocytes and made up of an N-terminal transcription factor portion (composed of an activation domain, a bHLHzip domain, and a nuclear localization signal), a hydrophobic region containing two membrane spanning regions, and a C-terminal regulatory segment. They recognize a symmetric sterol regulatory element (TCACNCCAC) instead of E-box. The family also includes Saccharomyces cerevisiae transcription factor HMS1 (also termed high-copy MEP suppressor protein 1) and serine-rich protein TYE7. HMS1 is a putative bHLHzip transcription factor involved in exit from mitosis and pseudohyphal differentiation. TYE7, also termed basic-helix-loop-helix protein SGC1, is a putative bHLHzip transcription activator required for Ty1-mediated glycolytic gene expression. TYE7 N-terminal is extremely rich in serine residues. It binds DNA on E-box motifs, 5'-CANNTG-3'. TYE7 is not essential for growth.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 357488103  46 RSKHSVTEQRRRSKINERFQILRDLIPQC-----------------DQKRDTASFLLEVIEYVQYLQERVQKYEGSYQGW 108
Cdd:cd11395    4 RLPHNAIEKRYRSNLNTKIERLRDAIPSLrspegksddgglgglapTTKLSKATILTKAIEYIRHLEQENERLEEENEEL 83

                 ...
gi 357488103 109 SQE 111
Cdd:cd11395   84 RQQ 86

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        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 357488103  47 SKHSVTEQRRRSKINERFQILRDLIPQCdQKRDTASFLLEVIEYVQYLQERVQKYEGSYQG 107
Cdd:cd11443    1 SKNLMAERRRRKKLNDRLYMLRSVVPKI-TKMDRASILGDAIDYVKELLQEINELQDELEG 60

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 357488103  49 HSVTEQRRRSKINERFQILRDLIPQCdQKRDTASFLLEVIEYVQYLQERVQKYE 102
Cdd:cd11449    9 HVEAERQRREKLNQRFYALRAVVPNV-SKMDKASLLGDAISYINELKSKVQDME 61

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in Saccharomyces cerevisiae centromere-binding protein 1 (CBP-1) and similar proteins; CBP-1, also termed centromere promoter factor 1 (CPF1), or centromere-binding factor 1 (CBF1), is a bHLHzip protein that is required for chromosome stability and methionine prototrophy. It binds as a homodimer to the centromere DNA elements I (CDEI, GTCACATG) region of the centromere that is required for optimal centromere function.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 357488103  46 RSKHSVTEQRRRSKINERFQILRDLIPQCDQKRDTASFLLEVIEYVQYLQE 96
Cdd:cd11398    8 RDNHKEVERRRRENINEGINELAALVPGNAREKNKGAILARAVEYIQELQE 58

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in Max-like protein X (Mlx) family; Mlx, also termed Class D basic helix-loop-helix protein 13 (bHLHd13), or Max-like bHLHZip protein, or protein BigMax, or transcription factor-like protein 4, is a Max-like bHLHZip transcription regulator that interacts with the Max network of transcription factors. It forms a sequence-specific DNA-binding protein complex with some member of Mad family (Mad1 and Mad4) and Mondo family but not the Myc family and bind the E-box DNA to control transcription. The family also includes Saccharomyces cerevisiae INO4, which is a bHLH transcriptional activator of phospholipid synthetic genes (such as INO1, CHO1/PSS, CHO2/PEM1, OPI3/PEM2, etc.). It is required for de-repression of phospholipid biosynthetic gene expression in response to inositol deprivation in yeast.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 357488103  45 IRSKHSVTEQRRRSKINERFQILRDLIPQCDQKRDT-ASFLLEVIEYVQYLQER 97
Cdd:cd11404    2 RRLNHVRSEKKRRELIKKGYDELCALVPGLDPQKRTkADILQKAADWIQELKEE 55

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 357488103  49 HSVTEQRRRSKINERFQILRDLIPQCDQKR-----DTASFLLEVIEYVQYLQERV 98
Cdd:cd11389    1 HKVIEKRRRDRINESLAELRRLVPEARKSKgsgklEKAEILEMTLQHLKALQSST 55

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in Max-like protein X (Mlx) and similar proteins; Mlx, also termed Class D basic helix-loop-helix protein 13 (bHLHd13), or Max-like bHLHZip protein, or protein BigMax, or transcription factor-like protein 4, is a Max-like bHLHZip transcription regulator that interacts with the Max network of transcription factors. It forms a sequence-specific DNA-binding protein complex with some member of Mad family (Mad1 and Mad4) and Mondo family but not the Myc family and bind the E-box DNA to control transcription.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 357488103  46 RSKHSVTEQRRRSKINERFQILRDLIPQC-------DQKRDTASFLLEVIEYVQYLQERVQKYE 102
Cdd:cd19687    3 REAHTQAEQKRRDAIKKGYDDLQDIVPTCqqqddigSQKLSKATILQRSIDYIQFLHQQKKKQE 66

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in USF/MITF family; The USF (upstream stimulatory factor)/MITF (microphthalmia-associated transcription factor) family includes two bHLHzip transcription factor subfamilies. USFs are ubiquitously expressed and key regulators of a wide number of gene regulation networks, including the stress and immune responses, cell cycle and proliferation, lipid and glucid metabolism. USFs recruit chromatin remodeling enzymes and interact with co-activators and the members of the transcription pre-initiation complex. USFs interact with high affinity to E-box regulatory elements. The MITF (also known as microphthalmia-TFE, or MiT) subfamily 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 subfamily proteins can form homodimers or heterodimers with each other but not with other bHLH or bHLHzip proteins.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 357488103  49 HSVTEQRRRSKINERFQILRDLIPQC-----DQKRDTASFLLEVIEYVQYLQERVQ 99
Cdd:cd11387    2 HNAVERRRRDNINEKIQELGSLVPPSrletkDLKPNKGSILSKAVEYIRELQNQNQ 57

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in protein Max and similar proteins; Max, also termed Class D basic helix-loop-helix protein 4 (bHLHd4), or Myc-associated factor X, is a bHLHZip transcription regulator that forms a sequence-specific DNA-binding protein complex with MYC or MAD which recognizes the core sequence 5'-CAC[GA]TG-3'. The MYC:MAX complex is a transcriptional activator, whereas the MAD:MAX complex is a transcriptional repressor. Max homodimer bind DNA but is transcriptionally inactive. Targeted deletion of max results in early embryonic lethality in mice.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 357488103  46 RSKHSVTEQRRRSKINERFQILRDLIPQCD-QKRDTASFLLEVIEYVQYLQERVQKYE 102
Cdd:cd11406    2 RAHHNALERKRRDHIKDSFHSLRDSVPSLQgEKASRAQILKKATEYIQYMRRKNHTHQ 59

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in Saccharomyces cerevisiae transcription factor HMS1 and similar proteins; HMS1, also termed high-copy MEP suppressor protein 1, is a putative bHLHzip transcription factor involved in exit from mitosis and pseudohyphal differentiation.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 357488103  46 RSKHSVTEQRRRSKINERFQILRDLIPQC--------DQKRDT--------------ASFLLEVIEYVQYLQERVQK 100
Cdd:cd11399    4 KTAHNMIEKRYRSNINDRIAELRDSVPALreayksarGEDEDEedlggltpatklnkATILSKATEYIRHLEKKNKR 80

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein FAMA and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as FAMA, MUTE and SPEECHLESS, which work together to regulate the sequential cell fate specification during stomatal development and differentiation. FAMA, also termed AtbHLH97, or EN 14, is a transcription activator required to promote differentiation and morphogenesis of stomatal guard cells and to halt proliferative divisions in their immediate precursors. It mediates the formation of stomata. MUTE, also termed AtbHLH45, or EN 20, is required for the differentiation of stomatal guard cells, by promoting successive asymmetric cell divisions and the formation of guard mother cells. It promotes the conversion of the leaf epidermis into stomata. SPEECHLESS, also termed AtbHLH98, or EN 19, is required for the initiation and the formation of stomata, by promoting the first asymmetric cell divisions. FAMA, MUTE and SPEECHLESS form heterodimers with SCREAM/ICE1 and SCRM2 to regulate transcription of genes during stomatal development.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 357488103  49 HSVTEQRRRSKINERFQILRDLIPQC-DQKRDTASFLLEVIEYVQYLQERVQKYE 102
Cdd:cd11448    3 HIAVERNRRKQMNEHLNVLRSLMPGSyIQRGDQASIVGGAIEFVKELEQLLQSLE 57

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in transcription factor AP-4 (TFAP4) and similar proteins; TFAP4, also termed activating enhancer-binding protein 4, or Class C basic helix-loop-helix protein 41 (bHLHc41), is a bHLHzip transcription factor that activates both viral and cellular genes involved in the regulation of cellular proliferation, stemness, and epithelial-mesenchymal transition by binding to the symmetrical DNA sequence 5'-CAGCTG-3'.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 357488103  53 EQRRRSKINERFQILRDLIPQCD-QKRDTASFLLEVIEYVQYLQERVQK 100
Cdd:cd11419   12 ERRRMQSINAGFQSLRTLLPHCDgEKLSKAAILQQTAEYIFSLEQEKTR 60

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 357488103  46 RSKHSVTEQRRRSKINERFQILRDLIP----QCDQKRDTASFLLEVIEYVQYLQ-ERVQ 99
Cdd:cd11405    4 RLSHISAEQKRRFNIKSGFDTLQSLIPslgqNPNQKVSKAAMLQKAAEYIKSLKrERQQ 62

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
                 ....*....|....*....|....*....|....*....|....*
gi 357488103  55 RRRSKINERFQILRDLIPQCDQKRDTASFLLEVIEYVQYLQERVQ 99
Cdd:cd11444    7 RGEEAIERRLRALRRLVPGGRESMEVEELLQETADYIMFLEMQVK 51

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in upstream stimulatory factor 2 (USF2) and similar proteins; USF2, also termed Class B basic helix-loop-helix protein 12 (bHLHb12), or major late transcription factor 2, or FOS-interacting protein (FIP), or upstream transcription factor 2, is a bHLHzip transcription factor that binds to a symmetrical DNA sequence (E-boxes) (5'-CACGTG-3') that is found in a variety of viral and cellular promoters.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 357488103  46 RSKHSVTEQRRRSKINERFQILRDLIPQC--DQKRDTAS---FLLEVIEYVQYLQERVQKYEGSYQ 106
Cdd:cd18923    9 RAQHNEVERRRRDKINNWIVQLSKIIPDCntDNSKTGASkggILSKACDYIRELRQTNQRMQETYK 74

basic Helix-Loop-Helix (bHLH) domain found in Saccharomyces cerevisiae INO4 and similar proteins; INO4 is a bHLH transcriptional activator of phospholipid synthetic genes (such as INO1, CHO1/PSS, CHO2/PEM1, OPI3/PEM2, etc.). It is required for de-repression of phospholipid biosynthetic gene expression in response to inositol deprivation in yeast. INO4 dimerizes with INO2 and binds to an UAS DNA element to control expression of the genes whose expression is inositol-responsive.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 357488103  44 VIRSKHSVTEQRRRSKINERFQILRDLIP--QCDQKRDTASFLLEVIEYVQYLQER 97
Cdd:cd11403    1 QKKENHISSEHKRREAIREGFDRLCAIVPalSSSQSRSEAVVYVKTVEYLKELYER 56

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.

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gi 357488103  46 RSKHSVTEQRRRSKINERFQILRDLIPQC---DQKRDTASFLLEVIEYVQYLQERVQK 100
Cdd:cd18925    6 KDNHNLIERRRRYNINYRIKELGTLIPKSndpDMRWNKGTILKASVEYIKWLQKEQQR 63

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana suppressor of acaulis 51 (SAC51) and similar proteins; SAC51, also termed AtbHLH142, or EN 128, is a bHLH transcription factor that is involved in stem elongation, probably by regulating a subset of genes involved in this process.

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gi 357488103  53 EQRRRSKINERFQILRDLIPQCDQKrDTASFLLEVIEYVQYLQERVQKYE 102
Cdd:cd18917    5 EKSRKEKIKKAVKLLRSIVPGGESM-DTALVLDEAIDYLKSLKMELQSLE 53

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 357488103  46 RSKHSVTEQRRRSKINERFQILRDLIPQcdQKRDTAS---FLLEVIEYVQYLQERVQ 99
Cdd:cd19690    1 RVSHKLAERKRRKEMKELFEDLRDALPQ--ERGTKASkweILTKAISYIQQLKRHIR 55

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in MLX-interacting protein (MLXIP) and similar proteins; 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.

                         10        20        30        40        50        60
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gi 357488103  46 RSKHSVTEQRRRSKINERFQILRDLIPQCDQKRDT--ASFLLEVIEYVQYLQ-ERVQKYE 102
Cdd:cd19688    4 RMKHISAEQKRRFNIKICFDTLNSLVSTLKNSKPIsnAITLQKTVEYIAKLQqERTQMQE 63