basic Helix-Loop-Helix-zipper (bHLHzip) domain found in N-Myc and similar proteins; N-Myc, also termed Class E basic helix-loop-helix protein 37 (bHLHe37), is a bHLHZip proto-oncogene protein that positively regulates the transcription of MYCNOS in neuroblastoma cells. It is also essential during embryonic development. N-Myc has a critical role in regulating the switch between proliferation and differentiation of progenitor cells. It binds DNA as a heterodimer with MAX. The family also includes S-Myc, encoded by rat or mouse intronless myc gene, which has apoptosis-inducing activity.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 648216291 167 EDSERRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQARQQQLLKK 246
Cdd:cd11456    1 EDSERRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEQKLLLEKEKLQARQQQLLKK 80

                 ....*..
gi 648216291 247 IEHARTC 253
Cdd:cd11456   81 IEQARTC 87

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in N-Myc and similar proteins; N-Myc, also termed Class E basic helix-loop-helix protein 37 (bHLHe37), is a bHLHZip proto-oncogene protein that positively regulates the transcription of MYCNOS in neuroblastoma cells. It is also essential during embryonic development. N-Myc has a critical role in regulating the switch between proliferation and differentiation of progenitor cells. It binds DNA as a heterodimer with MAX. The family also includes S-Myc, encoded by rat or mouse intronless myc gene, which has apoptosis-inducing activity.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 648216291 167 EDSERRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQARQQQLLKK 246
Cdd:cd11456    1 EDSERRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEQKLLLEKEKLQARQQQLLKK 80

                 ....*..
gi 648216291 247 IEHARTC 253
Cdd:cd11456   81 IEQARTC 87

helix loop helix domain;

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|...
gi 648216291   176 NILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEHQ 228
Cdd:smart00353   1 NARERRRRRKINEAFDELRSLLPTLPKNKKLSKAEILRLAIEYIKSLQEELQK 53

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in N-Myc and similar proteins; N-Myc, also termed Class E basic helix-loop-helix protein 37 (bHLHe37), is a bHLHZip proto-oncogene protein that positively regulates the transcription of MYCNOS in neuroblastoma cells. It is also essential during embryonic development. N-Myc has a critical role in regulating the switch between proliferation and differentiation of progenitor cells. It binds DNA as a heterodimer with MAX. The family also includes S-Myc, encoded by rat or mouse intronless myc gene, which has apoptosis-inducing activity.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 648216291 167 EDSERRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQARQQQLLKK 246
Cdd:cd11456    1 EDSERRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEQKLLLEKEKLQARQQQLLKK 80

                 ....*..
gi 648216291 247 IEHARTC 253
Cdd:cd11456   81 IEQARTC 87

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in the Myc family; The Myc family is a member of the bHLHzip family of transcription factors that play important roles in the control of normal cell proliferation, growth, survival and differentiation. All Myc isoforms contain two independently functioning polypeptide chain regions: N-terminal transactivating residues and a C-terminal bHLHzip segment. The bHLHzip family of bHLH transcription factors are characterized by a highly conserved N-terminal basic region that may bind DNA at a consensus hexanucleotide sequence known as the E-box (CANNTG) followed by HLH and leucine zipper motifs that may interact with other proteins to form homo- and heterodimers. Myc heterodimerizes with Max enabling specific binding to E-box DNA sequences in the promoters of target genes. The Myc proto-oncoprotein family includes at least five different functional members: c-, N-, L-, S- and B-Myc (which is lacking the bHLH domain).

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 648216291 171 RRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQARQQQLLKKIEH 249
Cdd:cd11400    1 KRRLHNVLERQRRNDLKNSFEKLRDLVPELADNEKASKVVILKKATEYIKQLQQEEKKLEKEKDKLKARNEQLRKKLER 79

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in c-Myc and similar proteins; c-Myc, also termed Myc proto-oncogene protein, or Class E basic helix-loop-helix protein 39 (bHLHe39), or transcription factor p64, a bHLHZip proto-oncogene protein that functions as a transcription factor, which binds DNA in a non-specific manner, yet also specifically recognizes the core sequence 5'-CAC[GA]TG-3'. It activates the transcription of growth-related genes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 648216291 167 EDSERRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQARQQQLLKK 246
Cdd:cd11458    1 EENDKRRTHNVLERQRRNELKLSFFALRDQIPEVANNEKAPKVVILKKATEYILSMQADEQRLISEKEQLRRRREQLKHR 80

                 ..
gi 648216291 247 IE 248
Cdd:cd11458   81 LE 82

Helix-loop-helix DNA-binding domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 648216291  171 RRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQ 223
Cdd:pfam00010   1 RREAHNERERRRRDRINDAFDELRELLPTLPPDKKLSKAEILRLAIEYIKHLQ 53

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
                 ....*....|....*....|....*....|....*....|....*.
gi 648216291 179 ERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQA 224
Cdd:cd00083    1 ERRRRDKINDAFEELKRLLPELPDSKKLSKASILQKAVEYIRELQS 46

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in MAX gene-associated protein (MGA) family; The MGA family includes MGA, Schizosaccharomyces pombe ESC1 (spESC1) and similar proteins. MGA, also termed MAX dimerization protein 5 (MAD5), is a dual specificity T-box/ bHLHzip transcription factor that regulates the expression of both Max-network and T-box family target genes. It contains a Myc-like bHLHZip motif and requires heterodimerization with Max for binding to the preferred Myc-Max-binding site CACGTG. In addition to the bHLHZip domain, MGA harbors a second DNA-binding domain, the T-box or T-domain. It thus binds the preferred Brachyury-binding sequence and represses transcription of reporter genes containing promoter-proximal Brachyury-binding sites. 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        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 648216291 172 RRNHNILERQRRNDLRSSFLTLRDHVPeLVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQ 237
Cdd:cd19682    1 RLRHKKRERERRSELRELFDKLKQLLG-LDSDEKASKLAVLTEAIEEIQQLKREEDELQKEKARLT 65

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 648216291 170 ERRRNHNILERQRRNDLRSSFLTLRDHVPELVKNE---------------KAAKVVILKKATEYVHSLQAEEHQLLLEKE 234
Cdd:cd11395    2 RKRLPHNAIEKRYRSNLNTKIERLRDAIPSLRSPEgksddgglgglapttKLSKATILTKAIEYIRHLEQENERLEEENE 81

                 ....*
gi 648216291 235 KLQAR 239
Cdd:cd11395   82 ELRQQ 86

basic helix-loop-helix (bHLH) domain found in factor in the germline alpha (FIGLA) and similar proteins; FIGLA, also termed FIGalpha, or Class C basic helix-loop-helix protein 8 (bHLHc8), or folliculogenesis-specific basic helix-loop-helix protein, or transcription factor FIGa, is a germ-cell-specific bHLH transcription factor expressed abundantly in female and less so in male germ cells. It is essential for primordial follicle formation and expression of many genes required for folliculogenesis, fertilization and early embryonic survival. FIGLA knockout mice cannot form primordial follicles and lose oocytes rapidly after birth, whereas male gonads are unaffected.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 648216291 172 RRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQA 224
Cdd:cd11422    1 RRVANARERERVRNLNSGFSKLRRIVPLIPRDRKPSKVDTLKGATEYIRLLQR 53

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        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 648216291 170 ERRRNHNILERQRRNDLRSSFLTLRDHVPelVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQARQQQL 243
Cdd:cd11398    6 QRRDNHKEVERRRRENINEGINELAALVP--GNAREKNKGAILARAVEYIQELQETEAKNIEKWTLEKLLTDQA 77

basic helix-loop-helix (bHLH) domain found in Drosophila melanogaster achaete-scute complex (AS-C) proteins, achaete-scute-like proteins, ASCL1-2, and similar proteins; This subfamily includes Drosophila melanogaster AS-C proteins and two ASCL family of transcription factors, ASCL-1 and ASCL-2. Drosophila melanogaster AS-C proteins includes lethal of scute (also known as achaete-scute complex protein T3 or AST3), scute (also known as achaete-scute complex protein T4 or AST4), achaete (also known as achaete-scute complex protein T5 or AST5), and asense (also known as achaete-scute complex protein T8 or AST8). They are involved in the determination of the neuronal precursors in the peripheral nervous system and the central nervous system, as well as in sex determination and dosage compensation. ASCL-1, also termed Class A basic helix-loop-helix protein 46 (bHLHa46), or achaete-scute homolog 1 (ASH-1), or mammalian achaete scute homolog 1 (Mash1), is expressed in subsets of neural progenitors in both the central and peripheral nervous system. It plays a key role in neuronal differentiation and specification in the nervous system. ASCL-2, also termed achaete-scute homolog 2 (ASH-2), or Class A basic helix-loop-helix protein 45 (bHLHa45), or mammalian achaete scute homolog 2 (Mash2), is involved in Schwann cell differentiation and control of proliferation in adult peripheral nerves.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 648216291 172 RRNHNilERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQ 223
Cdd:cd19723    4 RRNER--ERNRVKLVNLGFATLREHVPNGRANKKMSKVETLRSAVEYIRQLQ 53

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in sterol regulatory element-binding protein (SREBP) family; 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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 648216291 170 ERRRNHNILERQRRNDLRSSFLTLRDHV-PELVKNEKAAkvvILKKATEYVHSLQAEEHQLLLEKEKLQARQ 240
Cdd:cd11394    5 EKRSAHNAIEKRYRSSINDRIIELKDLVvGPDAKMNKSA---VLRKAIDYIRYLQKVNQKLKQENMALKKAL 73

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana Fe-deficiency induced transcription factor 1 (FIT) and similar proteins; The family includes bHLH transcription factors from Arabidopsis thaliana, such as FIT and DYT1. FIT, also termed FER-like iron deficiency-induced transcription factor, or FER-like regulator of iron uptake, or AtbHLH29, or EN 43, is a bHLH transcription factor that is required for the iron deficiency response in plant. It regulates FRO2 at the level of mRNA accumulation and IRT1 at the level of protein accumulation. DYT1, also termed AtbHLH22, or protein dysfunctional tapetum 1, or EN 49, is a bHLH transcription factor involved in the control of tapetum development. It is required for male fertility and pollen differentiation, especially during callose deposition.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 648216291 177 ILERQRRNDLRSSFLTLRDHVPELVKNEKAAkvvILKKATEYVHSLQAEEHQLLLEKEKLQARQQQLL 244
Cdd:cd11450    9 VSERNRRQKLNQRLFALRSVVPNITKMDKAS---IIKDAISYIQELQYQEKKLEAEIRELESRPPSTL 73

tissue specific basic helix-loop-helix (bHLH-TS) domain family; Tissue specific bHLH domain family includes transcription regulators whose expression are restricted to certain tissues. They are involved in cell-fate determination and process in neurogenesis, cardiogenesis, myogenesis, and hematopoiesis and include proteins from myogenic regulatory factor (MRF) family, twist-related protein (TWIST) family, scleraxis-like family, heart- and neural crest derivatives-expressed protein (HAND) family, helix-loop-helix protein (HEN) family, musculin-like family, germline alpha (FIGLA) family, T-cell acute lymphocytic leukemia protein/ lymphoblastic leukemia-derived sequence (TAL/LYL) family, ovary, uterus and testis protein (OUT) family, mesoderm posterior protein (Mesp) family, muscle, intestine and stomach expression 1 (MIST-1) family, protein atonal homologs (ATOH) family, neurogenin (NGN) family, neurogenic differentiation factor (NeuroD) family, achaete-scute complex-like (ASCL) family, Fer3-like protein (FERD3L)-like family, and Oligodendrocyte lineage genes (OLIG) family of transcription factors.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 648216291 172 RRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQ 223
Cdd:cd11390    1 RNAANARERRRMHDLNDAFEALRKVLPTVPPDKKLSKIETLRLAINYIAALS 52

basic helix-loop-helix (bHLH) domain found in achaete-scute-like protein 1 (ASCL-1) and similar proteins; ASCL-1, also termed Class A basic helix-loop-helix protein 46 (bHLHa46), or achaete-scute homolog 1 (ASH-1), or mammalian achaete scute homolog 1 (Mash1), is a neural-specific bHLH transcription factor that is expressed in subsets of neural progenitors in both the central and peripheral nervous system. It plays a key role in neuronal differentiation and specification in the nervous system.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 648216291 172 RRNHNilERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQaeehQLLLEKEKLQARQQ 241
Cdd:cd19742    8 RRNER--ERNRVKLVNMGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQ----QLLDEHDAVSAAFQ 71

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 648216291 171 RRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQ 237
Cdd:cd19688    3 RRMKHISAEQKRRFNIKICFDTLNSLVSTLKNSKPISNAITLQKTVEYIAKLQQERTQMQEETKRLR 69

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        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 648216291 172 RRNHNILERQRRNDLRSSFLTLRDHVPeLVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQ 237
Cdd:cd19690    1 RVSHKLAERKRRKEMKELFEDLRDALP-QERGTKASKWEILTKAISYIQQLKRHIRELRSEVNDLR 65

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana genes coding transcription factors and similar proteins; bHLH proteins are the second largest class of plant transcription factors that regulate transcription of genes that are involve in many essential physiological and developmental process. bHLH proteins are transcriptional regulators that are found in organisms from yeast to humans. The Arabidopsis bHLH proteins that have been characterized so far have roles in regulation of fruit dehiscence, cell development (carpel, anther and epidermal), phytochrome signaling, flavonoid biosynthesis, hormone signaling and stress responses.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 648216291 175 HNILERQRRNDLRSSFLTLRDHVPELVKNEKAAkvvILKKATEYVHSLQAEEHQL 229
Cdd:cd11393    1 HSIAERKRREKINERIRALRSLVPNGGKTDKAS---ILDEAIEYIKFLQEQVKVL 52

basic helix-loop-helix (bHLH) domain found in achaete-scute-like protein 2 (ASCL-2) and similar proteins; ASCL-2, also termed achaete-scute homolog 2 (ASH-2), or Class A basic helix-loop-helix protein 45 (bHLHa45), or mammalian achaete scute homolog 2 (Mash2), is a bHLH transcription factor that is involved in Schwann cell differentiation and control of proliferation in adult peripheral nerves.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 648216291 166 SEDSERRrnhNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQA 224
Cdd:cd19743    1 AAAVERR---NERERNRVKLVNLGFAALRQHVPQGGASKKMSKVETLRSAVEYIRALQR 56

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in Max-associated protein 3 (Mad3) and similar proteins; Mad3, also termed Max dimerization protein 3, or Max dimerizer 3 (MXD3), or Class C basic helix-loop-helix protein 13 (bHLHc13), or Max-interacting transcriptional repressor MAD3, or Myx, is a bHLHZip Max-interacting transcriptional repressor that plays an important role in cellular proliferation. It suppresses c-myc dependent transformation and is expressed during neural and epidermal differentiation.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 648216291 172 RRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQARQQQLLKKIE 248
Cdd:cd18932    7 RSVHNELEKHRRAQLRRCLEQLKQQVPLGADCSRYTTLSLLRRARLHIQKLEEQEQRAQQLKERLRWEQQKLRRRLE 83

basic helix-loop-helix (bHLH) domain found in achaete-scute-like proteins, ASCL3-5, and similar proteins; This subfamily includes three ASCL family of transcription factors, ASCL-3, ASCL-4 and ASCL-5. ASCL-3, also termed Class A basic helix-loop-helix protein 42 (bHLHa42), or bHLH transcriptional regulator Sgn-1, or achaete-scute homolog 3 (ASH-3), is specifically localized in the duct cells of the salivary glands. It may act as transcriptional repressor that inhibits myogenesis. ASCL-4, also termed Class A basic helix-loop-helix protein 44 (bHLHa44), or achaete-scute homolog 4 (ASH-4), or Hash4, may be involved in skin development. ASCL-5, also termed Class A basic helix-loop-helix protein 47 (bHLHa47), or achaete-scute homolog 5 (ASH-5), is an uncharacterized bHLH transcription factor that is close related to ASCL-3 and ASCL-4.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 648216291 171 RRRNHNilERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQA 224
Cdd:cd19724    3 RKRNER--ERQRVRCVNEGYARLRRHLPLENKDKRLSKVETLRAAIRYIKHLQE 54

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        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 648216291 171 RRRNHNILERQRRNDLRSSFLTLRDHVPELVKNE-----KAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQ 237
Cdd:cd19687    2 RREAHTQAEQKRRDAIKKGYDDLQDIVPTCQQQDdigsqKLSKATILQRSIDYIQFLHQQKKKQEEELSALR 73

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in Max-associated protein 4 (Mad4) and similar proteins; Mad4, also termed Max dimerization protein 4, or Max dimerizer 4 (MXD4), or Class C basic helix-loop-helix protein 12 (bHLHc12), or Max-interacting transcriptional repressor MAD4, is a bHLHZip Max-interacting transcriptional repressor that suppresses c-myc dependent transformation and is expressed during neural and epidermal differentiation. It is regulated by a transcriptional repressor complex that contains Miz-1 and c-Myc.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 648216291 172 RRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQARQQQLLKKIEH 249
Cdd:cd18929    3 RSSHNELEKHRRAKLRLYLEQLKQLVPLGPDSTRHTTLSLLKRAKMHIKKLEEQDRKALNIKEQLQREHRYLKRRLEQ 80

basic helix-loop-helix (bHLH) domain found in protein atonal homolog 8 (ATOH8) and similar proteins; ATOH8, also termed Class A basic helix-loop-helix protein 21 (bHLHa21), or helix-loop-helix protein hATH-6 (hATH6), is a bHLH shear-stress-responsive transcription factor expressed in activated satellite cells and proliferating myoblasts of human skeletal muscle tissue. It regulates endothelial cell proliferation, migration and tube-like structures formation. ATOH8 binds a palindromic (canonical) core consensus DNA sequence 5'-CANNTG- 3' known as an E-box element, possibly as a heterodimer with other bHLH proteins.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 648216291 170 ERRRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSL 222
Cdd:cd11421    7 QRRIEANARERTRVHTISAAFEALRKAVPSYSYNQKLSKLAILRIACSYILAL 59

basic helix-loop-helix (bHLH) domain found in scleraxis, transcription factor 15 (TCF-15) and similar proteins; The family includes scleraxis and transcription factor 15 (TCF-15). Scleraxis, also termed SCX, or Class A basic helix-loop-helix protein 41 (bHLHa41), or Class A basic helix-loop-helix protein 48 (bHLHa48), is a bHLH transcription factor that is expressed in sclerotome limb bud cranial and body wall mesenchyme, pericardium and heart valves, ligaments and tendons. It is required for tendon formation ligaments, connective tissue, the diaphragm, and testis development. Scleraxis plays a central role in promoting fibroblast proliferation and matrix synthesis during the embryonic development of tendons. TCF-15, also termed Class A basic helix-loop-helix protein 40 (bHLHa40), or paraxis, or protein bHLH-EC2, is a bHLH transcription factor expressed in caudal lateral and paraxial mesoderm dermomyotome and sclerotome fore limb buds during embryo development. It may function as an early transcriptional regulator involved in the patterning of the mesoderm and in lineage determination of cell types derived from the mesoderm.

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gi 648216291 172 RRNHNILERQRRNDLRSSFLTLRDHVPELVKNEKAAKVVILKKATEYVHSL 222
Cdd:cd11465    1 RQAANARERDRTHSVNSAFTALRTLIPTEPADRKLSKIETLRLASSYISHL 51

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').

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gi 648216291 170 ERRRNHNILERQRRNDLRSSFLTLRDHVpelVKNE-KAAKVVILKKATEYVHSLQAEEHQLLLEKEKLQARQQQ 242
Cdd:cd18921    5 EKRTAHNAIEKRYRSSINDKIIELKDLV---VGTEaKLNKSAVLRKAIDYIRFLQQSNQKLKQENMALKMAVQK 75

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.

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gi 648216291 175 HNILERQRRNDLRSSFLTLRDHVPELVKNEKAAkvvILKKATEYVHSLQAE 225
Cdd:cd11445    6 HNLSERRRRDRINEKMKALQELIPNCNKTDKAS---MLDEAIEYLKSLQLQ 53

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in upstream stimulatory factor 1 (USF1) and similar proteins; USF1, also termed Class B basic helix-loop-helix protein 11 (bHLHb11), or major late transcription factor 1, 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. It is ubiquitously expressed and involved in the transcription activation of various functional genes implicated in lipid and glucose metabolism, stress response, immune response, cell cycle control and tumour suppression. USF-1 recruits chromatin remodeling enzymes and interact with co-activators and the members of the transcription pre-initiation complex. Genetic polymorphisms of USF1 are associated with some metabolic and cardiovascular diseases, like diabetes, atherosclerosis, coronary artery calcifications and familial combined hyperlipidaemia (FCHL).

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gi 648216291 168 DSERRRNHNILERQRRNDLRSSFLTLRDHVPEL-VKNEKA--AKVVILKKATEYVHSLQAEEHQ 228
Cdd:cd18924    2 DEKRRAQHNEVERRRRDKINNWIVQLSKIIPDCsMESTKSgqSKGGILSKACDYIQELRQSNHR 65