basic helix-loop-helix (bHLH) domain found in T-cell acute lymphocytic leukemia protein 2 (TAL-2) and similar proteins; TAL-2, also termed Class A basic helix-loop-helix protein 19 (bHLHa19), is a bHLH transcription factor essential for the normal brain development. It has been implicated in T-cell acute lymphoblastic leukemia.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 4885619    2 TRKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVLGEQS 62
Cdd:cd19707   1 TRKIFTNTRERWRQQNVNSAFAELRKLIPTHPPDKKLSKNEILRLAMKYINFLVKLLGDQG 61

basic helix-loop-helix (bHLH) domain found in T-cell acute lymphocytic leukemia protein 2 (TAL-2) and similar proteins; TAL-2, also termed Class A basic helix-loop-helix protein 19 (bHLHa19), is a bHLH transcription factor essential for the normal brain development. It has been implicated in T-cell acute lymphoblastic leukemia.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 4885619    2 TRKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVLGEQS 62
Cdd:cd19707   1 TRKIFTNTRERWRQQNVNSAFAELRKLIPTHPPDKKLSKNEILRLAMKYINFLVKLLGDQG 61

Helix-loop-helix DNA-binding domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 4885619      3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFL 54
Cdd:pfam00010   1 RREAHNERERRRRDRINDAFDELRELLPTLPPDKKLSKAEILRLAIEYIKHL 52

basic helix-loop-helix (bHLH) domain found in T-cell acute lymphocytic leukemia protein 2 (TAL-2) and similar proteins; TAL-2, also termed Class A basic helix-loop-helix protein 19 (bHLHa19), is a bHLH transcription factor essential for the normal brain development. It has been implicated in T-cell acute lymphoblastic leukemia.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 4885619    2 TRKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVLGEQS 62
Cdd:cd19707   1 TRKIFTNTRERWRQQNVNSAFAELRKLIPTHPPDKKLSKNEILRLAMKYINFLVKLLGDQG 61

basic helix-loop-helix (bHLH) domain found in T-cell acute lymphocytic leukemia protein 1 (TAL-1) and similar proteins; TAL-1, also termed Class A basic helix-loop-helix protein 17 (bHLHa17), or stem cell protein (SCL), or T-cell leukemia/lymphoma protein 5, is a hematopoietic-specific bHLH transcription factor that functions in embryonic and adult hematopoiesis in vertebrates. It is also required for embryonic vascular remodeling. It acts as a regulator of erythroid differentiation and binds to regulatory regions of a large cohort of erythroid genes as part of a complex with GATA-1, LMO2 and Ldb1. TAL-1 has been implicated in T-cell acute lymphoblastic leukemia. In common with other tissue-specific bHLH proteins, Tal heterodimerizes with ubiquitously-expressed members of the E2A family and form a DNA-binding complex with an E-box (CANNTG) to regulate transcription at its recognition site.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 4885619    1 MTRKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVLGEQSLQ 64
Cdd:cd19706   2 VVRRIFTNSRERWRQQNVNGAFAELRKLIPTHPPDKKLSKNEILRLAMKYINFLAKLLNDQEEE 65

basic helix-loop-helix (bHLH) domain found in Drosophila melanogaster helix loop helix protein 3B (dHLH3B) and similar proteins; Drosophila HLH3B is an uncharacterized bHLH transcription factor that belongs to the T-cell acute lymphocytic leukemia protein/ lymphoblastic leukemia-derived sequence (TAL/LYL) family.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVLGEQS 62
Cdd:cd19708   1 RRMFTNSRERWRQQNVNGAFAELRKLVPTHPPDKKLSKNEILRLAIKYIRLLSNVLEWQK 60

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd11465   5 NARERDRTHSVNSAFTALRTLIPTEPADRKLSKIETLRLASSYISHLATVL 55

basic helix-loop-helix (bHLH) domain found in Fer3-like protein (FERD3L), pancreas transcription factor 1 subunit alpha (PTF1A) and similar proteins; The family corresponds to a group of bHLH transcription factors, including FERD3L and PTF1A. FERD3L, also termed basic helix-loop-helix protein N-twist, or Class A basic helix-loop-helix protein 31 (bHLHa31), or nephew of atonal 3 (NATO3), or Neuronal twist (NTWIST), is expressed in the developing central nervous system (CNS). It regulates floor plate (FP) cells development. FP is a critical organizing center located at the ventral-most midline of the neural tube. FERD3L binds to the E-box and functions as inhibitor of transcription. PTF1A, also termed Class A basic helix-loop-helix protein 29 (bHLHa29), or pancreas-specific transcription factor 1a, or bHLH transcription factor p48, or p48 DNA-binding subunit of transcription factor PTF1 (PTF1-p48), is implicated in the cell fate determination in various organs. It binds to the E-box consensus sequence 5'-CANNTG-3' and plays a role in early and late pancreas development and differentiation.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19686   6 NIRERKRMRSINDAFDGLRRHIPTFPYEKRLSKVDTLRLAIQYINFLTELL 56

basic helix-loop-helix (bHLH) domain found in twist-related protein 1 (TWIST1) and similar proteins; TWIST1, also termed Class A basic helix-loop-helix protein 38 (bHLHa38), or H-twist, is a bHLH transcriptional regulator that inhibits myogenesis by sequestrating E proteins, inhibiting trans-activation by MEF2, and inhibiting DNA-binding by MYOD1 through physical interaction. It also represses expression of proinflammatory cytokines such as TNFA and IL1B. In addition, TWIST1 is involved in cancer development and progression.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 4885619    2 TRKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDkKLSKNETLRLAMRYINFLVKVLGEQSL 63
Cdd:cd11412  11 TQRVMANVRERQRTQSLNEAFAALRKIIPTLPSD-KLSKIQTLKLAARYIDFLYQVLQSDEL 71

basic helix-loop-helix (bHLH) domain found in helix-loop-helix protein (HEN) family; The HEN family includes two neuron-specific bHLH transcription factors, HEN-1 (also known as Nhlh1 or bHLHa35 or NSCL-1) and HEN-2 (also known as Nhlh2 or bHLHa34 or NSCL-2). They may serve as DNA-binding protein that is involved in the control of cell-type determination, possibly within the developing nervous system.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 4885619    9 TRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd11414   8 TRERIRVEAFNSAFAQLRKLLPTLPPDKKLSKIEILRLAICYISYLNHVL 57

basic helix-loop-helix (bHLH) domain found in twist-related protein (TWIST) family; The TWIST family includes TWIST1 and TWIST2, which are highly homologous bHLH transcription factors that promote epithelial-mesenchymal transition (EMT) during development and tumor metastasis. They are involved in the negative regulation of cellular determination and in the differentiation of several lineages, including myogenesis, osteogenesis, and neurogenesis. TWIST factors express in broad partially-overlapping patterns during embryo development and dimerize with a broad sets of dimer partners that form numerous unique transcriptional complexes to regulate embryonic development.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDkKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd11464   1 QRVLANVRERQRTQSLNEAFTSLRKIIPTLPSD-KLSKIQTLKLAARYIDFLYQVL 55

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 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd11422   5 NARERERVRNLNSGFSKLRRIVPLIPRDRKPSKVDTLKGATEYIRLLQRIL 55

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 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19724   6 NERERQRVRCVNEGYARLRRHLPLENKDKRLSKVETLRAAIRYIKHLQELL 56

basic helix-loop-helix (bHLH) domain found in heart- and neural crest derivatives-expressed protein 1 (HAND1) and similar proteins; HAND1, also termed Class A basic helix-loop-helix protein 27 (bHLHa27), or extraembryonic tissues, heart, autonomic nervous system and neural crest derivatives-expressed protein 1 (eHAND), is a bHLH transcription factor that plays an essential role in both trophoblast-giant cells differentiation and in cardiac morphogenesis.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*...
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVLGE 60
Cdd:cd18952   2 RKGAGPKKERRRTESINSAFAELRECIPNVPADTKLSKIKTLRLATSYIAYLMDVLAK 59

basic helix-loop-helix (bHLH) domain found in pancreas transcription factor 1 subunit alpha (PTF1A) and similar proteins; PTF1A, also termed Class A basic helix-loop-helix protein 29 (bHLHa29), or pancreas-specific transcription factor 1a, or bHLH transcription factor p48, or p48 DNA-binding subunit of transcription factor PTF1 (PTF1-p48), is a bHLH transcription factor implicated in the cell fate determination in various organs. It binds to the E-box consensus sequence 5'-CANNTG-3' and plays a role in early and late pancreas development and differentiation.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd11417   6 NLRERRRMQSINDAFEGLRSHIPTLPYEKRLSKVDTLRLAIGYINFLSELV 56

basic helix-loop-helix (bHLH) domain found in Fer3-like protein (FERD3L) and similar proteins; FERD3L, also termed basic helix-loop-helix protein N-twist, or Class A basic helix-loop-helix protein 31 (bHLHa31), or nephew of atonal 3 (NATO3), or Neuronal twist (NTWIST), is a bHLH transcription factor expressed in the developing central nervous system (CNS). It regulates floor plate (FP) cells development. FP is a critical organizing center located at the ventral-most midline of the neural tube. FERD3L binds to the E-box and functions as inhibitor of transcription.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd11415  14 NIRERRRMFNLNEAFDKLRKKVPTFAYEKRLSRIETLRLAIVYISFMTDLL 64

basic helix-loop-helix (bHLH) domain found in protein atonal homologs ATOH1, ATOH7 and similar proteins; The family includes ATOH1 and ATOH7. ATOH1, also termed Class A basic helix-loop-helix protein 14 (bHLHa14), or helix-loop-helix protein hATH-1 (hATH1), or Math1, or Cath1, is a proneural bHLH transcription factor that is essential for inner ear hair cell differentiation. It dimerizes with E47 and activates E-box (CANNTG) dependent transcription. ATOH1 is a mammalian homolog of the Drosophila melanogaster gene atonal and mouse atonal homolog 1 (Math1). ATOH7, also termed Class A basic helix-loop-helix protein 13 (bHLHa13), or helix-loop-helix protein hATH-5 (hATH5), or Math5, is a bHLH transcription factor involved in the differentiation of retinal ganglion cells. The family also includes protein Amos (also termed absent MD neurons and olfactory sensilla protein, or reduced olfactory organs protein, or rough eye protein). It is a bHLH transcription factor that promotes multiple dendritic neuron formation in the Drosophila peripheral nervous system.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd11430   1 RRLAANARERRRMNGLNRAFDQLRSVVPSIGNDKKLSKYETLQMAQIYIETLSELL 56

basic helix-loop-helix (bHLH) domain found in helix-loop-helix protein 2 (HEN-2) and similar proteins; HEN-2, also termed nescient helix-loop-helix 2 (Nhlh2), or Class A basic helix-loop-helix protein 34 (bHLHa34), or nescient helix loop helix 2 (NSCL-2), is a neuron-specific bHLH transcription factor that may serve as DNA-binding protein and may be involved in the control of cell-type determination, possibly within the developing nervous system.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 4885619    9 TRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19702  22 TRERIRVEAFNLAFAELRKLLPTLPPDKKLSKIEILRLAICYISYLNHVL 71

basic helix-loop-helix (bHLH) domain found in Drosophila melanogaster protein Amos and similar proteins; Amos, also termed absent MD neurons and olfactory sensilla protein, or reduced olfactory organs protein, or rough eye protein, is a bHLH transcription factor that promotes multiple dendritic neuron formation in the Drosophila peripheral nervous system.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19715   8 RRLAANARERRRMNSLNVAFDKLRDVVPSLGDDRKLSKYETLQMAQSYITALKELL 63

basic helix-loop-helix (bHLH) domain found in neurogenin-2 (NGN-2) and similar proteins; NGN-2, also termed Class A basic helix-loop-helix protein 8 (bHLHa8), or protein atonal homolog 4 (ATOH4), is a neural-specific bHLH transcription factor required for sensory neurogenesis. It activates transcription by binding to the E box (5'-CANNTG-3').

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 4885619    2 TRKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19717   9 TRRVKANNRERNRMHNLNAALDSLREVLPTFPEDAKLTKIETLRFAHNYIWALSETL 65

basic helix-loop-helix (bHLH) domain found in protein atonal homolog 1 (ATOH1) and similar proteins; ATOH1, also termed Class A basic helix-loop-helix protein 14 (bHLHa14), or helix-loop-helix protein hATH-1 (hATH1), or Math1, or Cath1, is a proneural bHLH transcription factor that is essential for inner ear hair cell differentiation. It dimerizes with E47 and activates E-box (CANNTG) dependent transcription. ATOH1 is a mammalian homolog of the Drosophila melanogaster gene atonal and mouse atonal homolog 1 (Math1).

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19713   6 RRLAANARERRRMHGLNHAFDQLRNVIPSFNNDKKLSKYETLQMAQIYINALSELL 61

basic helix-loop-helix (bHLH) domain found in neurogenin-1 (NGN-1) and similar proteins; NGN-1, also termed Class A basic helix-loop-helix protein 6 (bHLHa6), or neurogenic basic-helix-loop-helix protein, or neurogenic differentiation factor 3 (NeuroD3), is a neural-specific bHLH transcription factor involved in the initiation of neuronal differentiation. It activates transcription by binding to the E box (5'-CANNTG-3').

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 4885619    2 TRKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19716  16 SRRVKANDRERNRMHNLNAALDELRSVLPSFPDDTKLTKIETLRFAHNYIWALSETL 72

basic helix-loop-helix (bHLH) domain found in muscle, intestine and stomach expression 1 (MIST-1) and similar proteins; MIST-1, also termed Class A basic helix-loop-helix protein 15 (bHLHa15), or Class B basic helix-loop-helix protein 8 (bHLHb8), is a bHLH transcription factor expressed in pancreatic acinar cells and other serous exocrine cells. It is essential for cytoskeletal organization and secretory activity. It also functions as a potent endoplasmic reticulum (ER) stress-inducible transcriptional regulator. MIST-1 is capable of binding to E-box (CANNTG) motifs as a homodimer or a heterodimer with E-proteins (E12 and E47) to regulate transcription.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19711   1 RRLESNERERQRMHKLNNAFQALREVIPHVRAEKKLSKIETLTLAKNYIKSLTTTI 56

basic helix-loop-helix (bHLH) domain found in neurogenic differentiation factor 6 (NeuroD6) and similar proteins; NeuroD6, also termed Class A basic helix-loop-helix protein 2 (bHLHa2), or protein atonal homolog 2 (ATH-2), or Atoh2, or Math2, or Nex1, is a neurogenic bHLH transcription factor involved in neuronal development, differentiation, and survival in Alzheimer's disease (AD) brains of both cohorts. It plays an integrative role in coordinating increase in mitochondrial mass with cytoskeletal remodeling, suggesting that it may act as a co-regulator of neuronal differentiation and energy metabolism.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19722  14 RRQEANARERNRMHGLNDALDSLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 69

basic helix-loop-helix (bHLH) domain found in musculin, transcription factor 21 (TCF-21) and similar proteins; The family includes two bHLH transcription factors, musculin and transcription factor 21 (TCF-21). Musculin, also termed activated B-cell factor 1 (ABF-1), or Class A basic helix-loop-helix protein 22 (bHLHa22), is a bHLH transcription factor expressed in activated B lymphocytes. It acts as a transcription repressor capable of inhibiting the transactivation capability of TCF3/E47. Musculin may play a role in regulating antigen-dependent B-cell differentiation. The mouse homolog, musculin, is suggested to be a repressor of myogenesis that is expressed in developing muscle and in the spleen. TCF-21, also termed capsulin, or Class A basic helix-loop-helix protein 23 (bHLHa23), or epicardin, or podocyte-expressed 1 (Pod-1), is a bHLH transcription factor expressed specifically in mesodermally-derived cells that surround the epithelium of the developing gastrointestinal, genitourinary and respiratory systems during mouse embryogenesis. It may play a role in the specification or differentiation of one or more subsets of epicardial cell types.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd11423   6 NARERARMRVLSKAFSRLKTTLPWVPPDTKLSKLDTLRLAASYIAHLRQIL 56

basic helix-loop-helix (bHLH) domain found in achaete-scute-like protein 5 (ASCL-5) and similar proteins; 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 belongs to AS-C (achaete, scute, lethal of scute, and asense) family.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19747  11 NERERQRVKCVNEGYARLRDHLPGAMAEKRLSKVETLRAAIRYIKYLQDLL 61

basic helix-loop-helix (bHLH) domain found in neurogenic differentiation factor 2 (NeuroD2) and similar proteins; NeuroD2, also termed Class A basic helix-loop-helix protein 1 (bHLHa1), or NeuroD-related factor (NDRF), is a neuronal calcium-dependent bHLH transcription factor that induces neuronal differentiation and promotes neuronal survival. It plays a central role in thalamocortical synaptic maturation. NeuroD2 mediates calcium-dependent transcription activation by binding to E box-containing promoter.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19720  35 RRQKANARERNRMHDLNSALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 90

basic helix-loop-helix (bHLH) domain found in Drosophila melanogaster protein dimmed and similar proteins; Dimmed, also termed DIMM, is a bHLH transcription factor that regulates neurosecretory (NS) cell function and neuroendocrine cell fate in Drosophila.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19712   1 RRLESNERERMRMHSLNDAFQGLREVIPHVNAERKLSKIETLTLAKNYIKALTNVI 56

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 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19723   6 NERERNRVKLVNLGFATLREHVPNGRANKKMSKVETLRSAVEYIRQLQQLL 56

basic helix-loop-helix (bHLH) domain found in musculin and similar proteins; Musculin, also termed activated B-cell factor 1 (ABF-1), or Class A basic helix-loop-helix protein 22 (bHLHa22), is a bHLH transcription factor expressed in activated B lymphocytes. It acts as a transcription repressor capable of inhibiting the transactivation capability of TCF3/E47. Musculin may play a role in regulating antigen-dependent B-cell differentiation. The mouse homolog, musculin, is suggested to be a repressor of myogenesis that is expressed in developing muscle and in the spleen. Musculin heterodimerizes with products of the E2A gene.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVLGE 60
Cdd:cd19703   9 NARERARMRVLSKAFSRLKTSLPWVPPDTKLSKLDTLRLASSYIAHLRQLLQE 61

basic helix-loop-helix (bHLH) domain found in Drosophila melanogaster achaete-scute complex (AS-C) proteins and similar proteins; 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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTH-----------PPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19744   6 NARERNRVKQVNNGFAILRQHIPQSviedltagggrGKSKKLSKVDTLRMAVEYIRRLQKLL 67

basic helix-loop-helix (bHLH) domain found in transcription factor 24 (TCF-24) and similar proteins; TCF-24 is an uncharacterized bHLH transcription factor that shows high sequence similarity with TCF-23.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 4885619   10 RERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19710   8 RERSRVQTLRSAFLELQRTLPSVPPDTKLSKLDVLVLATTYIAHLMRTL 56

basic helix-loop-helix (bHLH) domain found in neurogenic differentiation factor 1 (NeuroD1) and similar proteins; NeuroD1, also termed Class A basic helix-loop-helix protein 3 (bHLHa3), is a neuronal bHLH transcription factor involved in the development and maintenance of the endocrine pancreas and neuronal elements. It acts as an essential regulator of glutamatergic neuronal differentiation. Loss of NeuroD1 causes ataxia, cerebellar hypoplasia, sensorineural deafness, and severe retinal dystrophy in mice.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd19719  28 RRMKANARERNRMHGLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 83

basic helix-loop-helix (bHLH) domain found in Oligodendrocyte lineage genes (OLIG) family of transcription factors; The OLIG family includes three bHLH transcription factors, Oligo1-3, which are expressed in both the developing and mature central nervous system. Oligo1 and Oligo2 are expressed in a nervous tissue-specific manner, but Oligo3 is found mainly in non-neural tissues. Oligo (also known as Olig) have key roles in the specification of motor neurons, dorsal interneurons, and oligodendrocytes. Oligo1, also termed Class B basic helix-loop-helix protein 6 (bHLHb6), or Class E basic helix-loop-helix protein 21 (bHLHe21), promotes formation and maturation of oligodendrocytes, especially within the brain. Oligo2, also termed Class B basic helix-loop-helix protein 1 (bHLHb1), or Class E basic helix-loop-helix protein 19 (bHLHe19), or protein kinase C-binding protein 2, or protein kinase C-binding protein RACK17, is required for oligodendrocyte and motor neuron specification in the spinal cord, as well as for the development of somatic motor neurons in the hindbrain. It cooperates with OLIG1 to establish the MN progenitors (pMN) domain of the embryonic neural tube. Oligo3, also termed Class B basic helix-loop-helix protein 7 (bHLHb7), or Class E basic helix-loop-helix protein 20 (bHLHe20), is expressed in the ventricular zone of the dorsal alar plate of the hindbrain and involved in regulating the development of dorsal and ventral spinal cord. It may determine the distinct specification program of class A neurons in the dorsal part of the spinal cord and suppress specification of class B neurons. This family also includes two OLIG-related bHLH transcription factors, bHLHe22 and bHLHe23. bHLHe22, also termed Class B basic helix-loop-helix protein 5 (bHLHb5), or trinucleotide repeat-containing gene 20 protein, is a neural-specific transcriptional repressor that is expressed in both excitatory (unipolar brush cells) and inhibitory neurons (cartwheel cells) of the dorsal cochlear nucleus (DCN) during development. It is important for the proper development and/or survival of a number of neural cell types. bHLHe23, also termed Class B basic helix-loop-helix protein 4 (bHLHb4), is expressed in rod bipolar cells and is required for rod bipolar cell maturation. bHLHe23 have roles in spinal interneuron differentiation by mechanisms linked to the Notch signaling pathway. It modulates the expression of genes required for the differentiation and/or maintenance of pancreatic and neuronal cell types.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIP--THPPDKKLSKNETLRLAMRYINFLVKVLGE 60
Cdd:cd11429   5 NSRERKRMHDLNSALDGLRSVMPyaQGPSVRKLSKIATLLLARNYILMLTQALEE 59

basic helix-loop-helix (bHLH) domain found in DNA-binding protein inhibitor ID4 and similar proteins; ID4, also termed Class B basic helix-loop-helix protein 27 (bHLHb27), or inhibitor of DNA binding 4, or inhibitor of differentiation 4, is a dominant negative helix-loop-helix (dnHLH) transcriptional regulator (lacking a basic DNA binding domain) which negatively regulates the bHLH transcription factors by forming heterodimers and inhibiting their DNA binding and transcriptional activity. It plays a role in adipose cell differentiation.

                        10        20        30
                ....*....|....*....|....*....|....*..
gi 4885619   15 QQNVNSAFAKLRKLIPTHPPDKKLSKNETLRLAMRYI 51
Cdd:cd19694   8 QYDMNDCYSRLKRLVPTIPPNKKVSKVEILQHVIDYI 44

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        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 4885619    1 MTRKIfTNTRERWRQQNVNSAFAKLRKLIPtHPPDKKLSKNETLRLAMRYINFL 54
Cdd:cd11419   3 IRREI-ANSNERRRMQSINAGFQSLRTLLP-HCDGEKLSKAAILQQTAEYIFSL 54

basic helix-loop-helix (bHLH) domain found in Class E basic helix-loop-helix protein 22 (bHLHe22) and similar proteins; bHLHe22, also termed Class B basic helix-loop-helix protein 5 (bHLHb5), or trinucleotide repeat-containing gene 20 protein, is an OLIG-related bHLH neural-specific transcriptional repressor that is expressed in both excitatory (unipolar brush cells) and inhibitory neurons (cartwheel cells) of the dorsal cochlear nucleus (DCN) during development. It is important for the proper development and/or survival of a number of neural cell types.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIP-THPPD-KKLSKNETLRLAMRYI 51
Cdd:cd18954   6 NARERRRMHDLNDALDELRAVIPyAHSPSvRKLSKIATLLLAKNYI 51

basic helix-loop-helix (bHLH) domain found in Class E basic helix-loop-helix protein bHLHe22, bHLHe23 and similar proteins; The family includes two OLIG-related bHLH transcription factors, bHLHe22 and bHLHe23. bHLHe22, also termed Class B basic helix-loop-helix protein 5 (bHLHb5), or trinucleotide repeat-containing gene 20 protein, is a neural-specific transcriptional repressor that is expressed in both excitatory (unipolar brush cells) and inhibitory neurons (cartwheel cells) of the dorsal cochlear nucleus (DCN) during development. It is important for the proper development and/or survival of a number of neural cell types. bHLHe23, also termed Class B basic helix-loop-helix protein 4 (bHLHb4), is expressed in rod bipolar cells and is required for rod bipolar cell maturation. bHLHe23 have roles in spinal interneuron differentiation by mechanisms linked to the Notch signaling pathway. It modulates the expression of genes required for the differentiation and/or maintenance of pancreatic and neuronal cell types.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIP--THPPDKKLSKNETLRLAMRYINFLVKVLGE 60
Cdd:cd11468   5 NARERRRMHDLNDALDDLRAVIPyaHSPSVRKLSKIATLLLAKNYILMQARAIEE 59

basic helix-loop-helix (bHLH) domain found in myoblast determination protein 1 (MYOD1) and similar proteins; MYOD1, also termed Class C basic helix-loop-helix protein 1 (bHLHc1), or myogenic factor 3 (Myf-3), is a bHLH transcriptional activator that promotes transcription of muscle-specific target genes and plays a role in muscle differentiation. Together with Myf-5 and MYOG, MYOD1 co-occupies muscle-specific gene promoter core region during myogenesis.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKLRKLIPTHpPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd18936   6 RRKAATMRERRRLSKVNEAFETLKRCTSTN-PNQRLPKVEILRNAIRYIESLQALL 60

basic helix-loop-helix (bHLH) domain found in oligodendrocyte transcription factor 1 (Oligo1) and similar proteins; Oligo1, also termed Class B basic helix-loop-helix protein 6 (bHLHb6), or Class E basic helix-loop-helix protein 21 (bHLHe21), is a bHLH transcription factor that promotes formation and maturation of oligodendrocytes, especially within the brain.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 4885619    1 MTRKIftNTRERWRQQNVNSAFAKLRKLI------PTHP-PDKKLSKNETLRLAMRYINFLVKVLGE 60
Cdd:cd18942   6 LRRKI--NSRERKRMQDLNLAMDALREVIlpysaaHCQSsPGRKLSKIATLLLARNYILLLGSSLQE 70

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
                ....*....|....*....|....*....|....*....|....*..
gi 4885619   11 ERWRQQNVNSAFAKLRKLIPTHP---PDKKLSKNETLRLAMRYINFL 54
Cdd:cd11387   6 ERRRRDNINEKIQELGSLVPPSRletKDLKPNKGSILSKAVEYIREL 52

basic helix-loop-helix (bHLH) domain found in Saccharomyces cerevisiae protein INO2 and similar proteins; INO2 is a positive regulatory factor required for depression of the co-regulated phospholipid biosynthetic enzymes in Saccharomyces cerevisiae. It is also involved in the expression of ITR1.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 4885619    1 MTRKIFTNTRERWRQQNVNSAFAKLRKLIPTHP--PDKKLSKNETLRLAMRYI 51
Cdd:cd11388   1 PVKKWKHVEAEKKRRNQIKKGFEDLINLINYPRnnNEKRISKSELLNKAVDDI 53

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 4885619    8 NTRERWRQQNVNSAFAKLRKLIPTHPPdkKLSKNETLRLAMRYINFLVKVLGEQ 61
Cdd:cd19683   7 NAKERQRRERIKIACDQLRKLVPGCSR--KTDKATVFEFTVAYIKFLREKLGDS 58

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
                ....*....|....*....|....*....|....*....|....*....
gi 4885619    8 NTRERWRQQNVNSAFAKLRKLIPThPPDKKLSKNETLRLAMRYINFLVK 56
Cdd:cd19682   5 KKRERERRSELRELFDKLKQLLGL-DSDEKASKLAVLTEAIEEIQQLKR 52

basic helix-loop-helix (bHLH) domain found in myogenic regulatory factor (MRF) family; MRFs are a family of muscle-specific bHLH transcription proteins (MyoD, Myf5, Mrf4 and MyoG) that plays an essential role in regulating skeletal muscle development and growth. MRFs are capable of binding to E-box motifs as a heterodimer with E-proteins to regulate transcription expression.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 4885619   10 RERWRQQNVNSAFAKLRKLIPTHpPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd11411   9 RERRRLKKVNEAFEALKRCTSAN-PNQRLPKVEILRNAIEYIESLQDLL 56

basic helix-loop-helix (bHLH) domain found in muscle-specific regulatory factor 4 (MRF4) and similar proteins; MRF4, also termed Class C basic helix-loop-helix protein 4 (bHLHc4), or myogenic factor 6 (Myf-6), is a bHLH transcription factor associated with myogenesis. It plays a role in skeletal muscle differentiation.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 4885619    3 RKIFTNTRERWRQQNVNSAFAKL-RKLIPThpPDKKLSKNETLRLAMRYINFLVKVL 58
Cdd:cd18934   2 RRKAATLRERRRLKKINEAFEALkRRTVPN--PNQRLPKVEILRSAINYIEKLQDLL 56