Neuronal helix-loop-helix transcription factor; This domain family is found in eukaryotes, and is approximately 80 amino acids in length. The family is found C-terminal to pfam00010. There is a single completely conserved residue W that may be functionally important. Neuronal basic helix-loop-helix (bHLH) transcription factors such as neuroD and neurogenin have been shown to play important roles in neuronal development.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958660507 180 GKRPDLVSYVQTLCKGLSQPTTNLVAGCLQLNSRNFLTEQGADgagRFHGSGGP-FAMHPYPYPCSRLAGAQcqaAGGLG 258
Cdd:pfam12533   1 GKRPDLLSFVQTLCKGLSQPTTNLVAGCLQLNPRNFLPEQMEE---RPGGPGSPlHPGHPYSYQSPGLPSPP---YGTMD 74

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1958660507 259 GGAAHALRTHGYCAAYETLYaaagGGGASPDYNSSEYEGPLSPPLCLNGNFS 310
Cdd:pfam12533  75 SSHLLHLRTYGYCSPYESLY----SESSSPDYYSPPYDGPLSPPLSISGNFS 122

Neuronal helix-loop-helix transcription factor; This domain family is found in eukaryotes, and is approximately 80 amino acids in length. The family is found C-terminal to pfam00010. There is a single completely conserved residue W that may be functionally important. Neuronal basic helix-loop-helix (bHLH) transcription factors such as neuroD and neurogenin have been shown to play important roles in neuronal development.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958660507 180 GKRPDLVSYVQTLCKGLSQPTTNLVAGCLQLNSRNFLTEQGADgagRFHGSGGP-FAMHPYPYPCSRLAGAQcqaAGGLG 258
Cdd:pfam12533   1 GKRPDLLSFVQTLCKGLSQPTTNLVAGCLQLNPRNFLPEQMEE---RPGGPGSPlHPGHPYSYQSPGLPSPP---YGTMD 74

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1958660507 259 GGAAHALRTHGYCAAYETLYaaagGGGASPDYNSSEYEGPLSPPLCLNGNFS 310
Cdd:pfam12533  75 SSHLLHLRTYGYCSPYESLY----SESSSPDYYSPPYDGPLSPPLSISGNFS 122

helix loop helix domain;

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|...
gi 1958660507  127 NARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILRS 179
Cdd:smart00353   1 NARERRRRRKINEAFDELRSLLPTLPKNKKLSKAEILRLAIEYIKSLQEELQK 53

Neuronal helix-loop-helix transcription factor; This domain family is found in eukaryotes, and is approximately 80 amino acids in length. The family is found C-terminal to pfam00010. There is a single completely conserved residue W that may be functionally important. Neuronal basic helix-loop-helix (bHLH) transcription factors such as neuroD and neurogenin have been shown to play important roles in neuronal development.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958660507 180 GKRPDLVSYVQTLCKGLSQPTTNLVAGCLQLNSRNFLTEQGADgagRFHGSGGP-FAMHPYPYPCSRLAGAQcqaAGGLG 258
Cdd:pfam12533   1 GKRPDLLSFVQTLCKGLSQPTTNLVAGCLQLNPRNFLPEQMEE---RPGGPGSPlHPGHPYSYQSPGLPSPP---YGTMD 74

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1958660507 259 GGAAHALRTHGYCAAYETLYaaagGGGASPDYNSSEYEGPLSPPLCLNGNFS 310
Cdd:pfam12533  75 SSHLLHLRTYGYCSPYESLY----SESSSPDYYSPPYDGPLSPPLSISGNFS 122

basic helix-loop-helix (bHLH) domain found in neurogenic differentiation factor 4 (NeuroD4) and similar proteins; NeuroD4, also termed Class A basic helix-loop-helix protein 4 (bHLHa4), or protein atonal homolog 3 (ATH-3), or Atoh3, or Math-3, is a bHLH transcriptional activator that mediates neuronal differentiation.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1958660507 111 MTKARLERSKLRRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILRS 179
Cdd:cd19721    19 MTKARLERFRARRVKANARERSRMHGLNDALDNLRRVMPCYSKTQKLSKIETLRLARNYIWALSEVLET 87

basic helix-loop-helix (bHLH) domain found in neurogenic differentiation factor (NeuroD) family; The NeuroD family includes NeuroD1, NeuroD2, NeuroD4 and NeuroD6. 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. 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. NeuroD4, also termed Class A basic helix-loop-helix protein 4 (bHLHa4), or protein atonal homolog 3 (ATH-3), or Atoh3, or Math-3, is a bHLH transcriptional activator that mediates neuronal differentiation. 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 1958660507 123 RQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd11427     1 RVKANARERNRMHGLNDALDNLRKVVPCYSKTQKLSKIETLRLARNYIWALSEIL 55

basic helix-loop-helix (bHLH) domain found in neurogenin (NGN) family; The NGN family includes three neural-specific bHLH transcription factors, NGN1-3, which may function at neuroblast selection genes during the development of several neuronal lineages. 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. 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. NGN-3, also termed Class A basic helix-loop-helix protein 7 (bHLHa7), or protein atonal homolog 5 (ATOH5), is a neural-specific bHLH transcription factor expressed in the developing central nervous system and the embryonic pancreas. It is involved in neurogenesis and plays an important role in spermatogenesis.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILR 178
Cdd:cd11428     1 RRLKANDRERNRMHNLNDALDALREVLPSFPDETKLTKIETLRFAHNYIWALSETLK 57

basic helix-loop-helix (bHLH) domain found in neurogenin-3 (NGN-3) and similar proteins; NGN-3, also termed Class A basic helix-loop-helix protein 7 (bHLHa7), or protein atonal homolog 5 (ATOH5), is a neural-specific bHLH transcription factor expressed in the developing central nervous system and the embryonic pancreas. It is involved in neurogenesis and plays an important role in spermatogenesis.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILR 178
Cdd:cd19718     8 RRMKANDRERNRMHNLNSALDALRSVLPTFPDDAKLTKIETLRFAHNYIWALTETLR 64

basic helix-loop-helix (bHLH) domain found in Drosophila melanogaster protein taxi and similar proteins; Protein taxi, also termed protein delilah (Dei), is a bHLH transcription factor that is involved in regulation of cell adhesion and attachment that is expressed in specialized cells that provide anchoring sites to either muscles (tendon cells), or proprioceptors (chordotonal attachment cells) during embryonic development. It probably plays an important role in the differentiation of epidermal cells into the tendon cells that form the attachment sites for all muscles.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCY---SKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd11431     1 RRKTANARERDRMREINDAFEALRRAVPEYpvaGKDGKLTKITTLRLAMNYIKALTDLL 59

basic helix-loop-helix (bHLH) domain found in protein atonal homolog 7 (ATOH7) and similar proteins; 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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1958660507 115 RLERSKLRRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILRSGKR 182
Cdd:cd19714     1 RLESAARRRLAANARERRRMQGLNTAFDRLRKVVPQWGQDKKLSKYETLQMALSYIMALTRILAEAER 68

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 1958660507 120 KLRRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd19715     6 KKRRLAANARERRRMNSLNVAFDKLRDVVPSLGDDRKLSKYETLQMAQSYITALKELL 63

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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958660507 120 KLRRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILRS 179
Cdd:cd19713     4 KQRRLAANARERRRMHGLNHAFDQLRNVIPSFNNDKKLSKYETLQMAQIYINALSELLQG 63

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 1958660507 123 RQKANARERNRMHDLNAALDNLRKVVPCY--SKTQKLSKIETLRLAKNYIWALSEILRS 179
Cdd:cd11429     1 RLKINSRERKRMHDLNSALDGLRSVMPYAqgPSVRKLSKIATLLLARNYILMLTQALEE 59

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 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd19712     1 RRLESNERERMRMHSLNDAFQGLREVIPHVNAERKLSKIETLTLAKNYIKALTNVI 56

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 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd19711     1 RRLESNERERQRMHKLNNAFQALREVIPHVRAEKKLSKIETLTLAKNYIKSLTTTI 56

basic helix-loop-helix (bHLH) domain found in achaete-scute complex-like (ASCL) family; The achaete-scute complex-like (ASCL, also known as achaete-scute complex homolog or ASH) family of bHLH transcription factors, ASCL1-5, have been implicated in cell fate specification and differentiation. They are critical for proper development of the nervous system. The deregulation of ASCL plays a key role in psychiatric and neurological disorders. 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. 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. 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 a bHLH transcription factor specifically localized in the duct cells of the salivary glands. It may act as transcriptional repressor that inhibits myogenesis. The family also includes Drosophila melanogaster achaete-scute complex (AS-C) proteins, which consists of 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
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd11418     1 RVARRNERERRRVQAVNDAFDRLRQHVPYLKRRKKLSKVKTLRRAIEYIRHLQKLL 56

basic helix-loop-helix (bHLH) domain found in Caenorhabditis elegans Helix-loop-helix protein 13 (HLH13) and similar proteins; Caenorhabditis elegans HLH13, also termed Fer3-like protein, or nephew of atonal 3, is a bHLH transcription factor that plays a role in the negative regulation of exit from L1 arrest and dauer diapause dependent on IIS signaling (insulin and insulin-like growth factor (IGF) signaling).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1958660507 120 KLRRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILRSG 180
Cdd:cd11416     3 KVQRHAANIRERKRMLSINSAFEELRCHVPTFPYEKRLSKIDTLRLAIAYIALLRDILRSG 63

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        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1958660507 123 RQKANARERNRMHDLNAALDNLRKVVPcYSKT---QKLSKIETLRLAKNYIWALSEILRSGKRpdLVSYVQ 190
Cdd:cd18954     2 RLNINARERRRMHDLNDALDELRAVIP-YAHSpsvRKLSKIATLLLAKNYILMQANALEEMRR--LVAYLN 69

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        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1958660507 117 ERSKLRRqKANARERNRMHDLNAALDNLRKVVPCYSKT-------QKLSKIETLRLAKNYIWALSEILRSGKR 182
Cdd:cd18942     2 EQQQLRR-KINSRERKRMQDLNLAMDALREVILPYSAAhcqsspgRKLSKIATLLLARNYILLLGSSLQELRR 73

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 1958660507 123 RQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILR 178
Cdd:cd11422     1 RRVANARERERVRNLNSGFSKLRRIVPLIPRDRKPSKVDTLKGATEYIRLLQRILE 56

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 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSkTQKLSKIETLRLAKNYIWALSEILRSG 180
Cdd:cd11464     1 QRVLANVRERQRTQSLNEAFTSLRKIIPTLP-SDKLSKIQTLKLAARYIDFLYQVLRSD 58

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 1958660507 127 NARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd19723     6 NERERNRVKLVNLGFATLREHVPNGRANKKMSKVETLRSAVEYIRQLQQLL 56

basic helix-loop-helix (bHLH) domain found in oligodendrocyte transcription factor 2 (Oligo2) and similar proteins; 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 a bHLH transcription factor that 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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1958660507 123 RQKANARERNRMHDLNAALDNLRKVVPCY--SKTQKLSKIETLRLAKNYIWALSEILRSGKR 182
Cdd:cd18940    16 RLKINSRERKRMHDLNIAMDGLREVMPYAhgPSVRKLSKIATLLLARNYILMLTNSLEEMKR 77

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
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILR 178
Cdd:cd19708     1 RRMFTNSRERWRQQNVNGAFAELRKLVPTHPPDKKLSKNEILRLAIKYIRLLSNVLE 57

basic helix-loop-helix (bHLH) domain found in scleraxis and similar proteins; 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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILRSGK 181
Cdd:cd18951     4 QRHTANARERDRTNSVNTAFTALRTLIPTEPADRKLSKIETLRLASSYISHLGNVLLVGE 63

basic helix-loop-helix (bHLH) domain found in heart- and neural crest derivatives-expressed protein 2 (HAND2) and similar proteins; HAND2, also termed Class A basic helix-loop-helix protein 26 (bHLHa26), or deciduum, heart, autonomic nervous system and neural crest derivatives-expressed protein 2 (dHAND), is a bHLH transcription factor that is essential for cardiac morphogenesis, particularly for the formation of the right ventricle and of the aortic arch arteries.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd11471     1 RRGTANRKERRRTQSINSAFAELRECIPNVPADTKLSKIKTLRLATSYIAYLMDLL 56

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
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILRS 179
Cdd:cd19707     2 RKIFTNTRERWRQQNVNSAFAELRKLIPTHPPDKKLSKNEILRLAMKYINFLVKLLGD 59

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 1958660507 130 ERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSE 175
Cdd:cd00083     1 ERRRRDKINDAFEELKRLLPELPDSKKLSKASILQKAVEYIRELQS 46

basic helix-loop-helix (bHLH) domain found in the mesoderm posterior protein (Mesp) family; Mesp, a bHLH tissue specific transcription factor, acts as a key regulator of the cardiovascular transcriptional network by inducing directly and/or indirectly the expression of the majority of key cardiovascular transcription factors. The Mesp family includes two bHLH transcription factors, Mesp1 and Mesp2. Mesp1, also termed Class C basic helix-loop-helix protein 5 (bHLHc5), promotes cardiovascular differentiation during embryonic development and embryonic stem cell differentiation. Mesp2, also termed Class C basic helix-loop-helix protein 6 (bHLHc6), plays an important role in somitogenesis.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVP--CYSKTQKLSKIETLRLAKNYIWALSEILRSGKRP 183
Cdd:cd18938     1 QRQSASEREKLRMRDLAKALHNLRRYLPpsVAPAGQSLTKIETLRLTIRYISHLSAQLGLSEES 64

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 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd11423     1 QRNAANARERARMRVLSKAFSRLKTTLPWVPPDTKLSKLDTLRLAASYIAHLRQIL 56

basic helix-loop-helix (bHLH) domain found in protein lyl-1 and similar proteins; Lyl-1, also termed Class A basic helix-loop-helix protein 18 (bHLHa18), or lymphoblastic leukemia-derived sequence 1, is a proto-oncogenic bHLH transcription factor involved in T-cell acute lymphoblastic leukemia. It plays an important role in hematopoietic stem cell function and is required for the late stages of postnatal angiogenesis to limit the formation of new blood vessels, notably by regulating the activity of the small GTPase Rap1. LYL-1 deficiency induces a stress erythropoiesis.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEILR 178
Cdd:cd19705     6 RRVFTNSRERWRQQNVNGAFAELRKLIPTHPPDKKLSKNEILRLAMKYIDFLVTLLR 62

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 1958660507 119 SKLRRQKANARERNRMHDLNAALDNLRKVVPCYSKtQKLSKIETLRLAKNYIWAL 173
Cdd:cd11419     1 RRIRREIANSNERRRMQSINAGFQSLRTLLPHCDG-EKLSKAAILQQTAEYIFSL 54

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
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1958660507 127 NARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd19742    10 NERERNRVKLVNMGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 60

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 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd18952     2 RKGAGPKKERRRTESINSAFAELRECIPNVPADTKLSKIKTLRLATSYIAYLMDVL 57

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 1958660507 124 QKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd19743     5 ERRNERERNRVKLVNLGFAALRQHVPQGGASKKMSKVETLRSAVEYIRALQRLL 58

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 1958660507 122 RRQKANARERNRMHDLNAALDNL-RKVVPcySKTQKLSKIETLRLAKNYIWALSEILRS 179
Cdd:cd18934     2 RRKAATLRERRRLKKINEAFEALkRRTVP--NPNQRLPKVEILRSAINYIEKLQDLLHS 58

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 1958660507 124 QKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd19747     8 QKRNERERQRVKCVNEGYARLRDHLPGAMAEKRLSKVETLRAAIRYIKYLQDLL 61

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 1958660507 128 ARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd11414     8 TRERIRVEAFNSAFAQLRKLLPTLPPDKKLSKIEILRLAICYISYLNHVL 57

basic helix-loop-helix (bHLH) domain found in achaete-scute-like protein 4 (ASCL-4) and similar proteins; ASCL-4, also termed Class A basic helix-loop-helix protein 44 (bHLHa44), or achaete-scute homolog 4 (ASH-4), or Hash4, is a bHLH transcriptional regulator that may be involved in skin development.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1958660507 124 QKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd19746    10 RKRNERERQRVRCVNEGYARLREHLPQELADKRLSKVETLRAAIDYIKHLQELL 63

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        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVpCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd11411     2 RRKAATMRERRRLKKVNEAFEALKRCT-SANPNQRLPKVEILRNAIEYIESLQDLL 56

basic helix-loop-helix (bHLH) domain found in achaete-scute-like protein 3 (ASCL-3) and similar proteins; 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 a bHLH transcription factor specifically localized in the duct cells of the salivary glands. It may act as transcriptional repressor that inhibits myogenesis.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1958660507 124 QKANARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd19745     6 RKRNERERQRVKCVNEGYAKLRRHLPQEYSEKRLSKVETLRAAIKYIKHLQSVL 59

basic helix-loop-helix (bHLH) domain found in ovary, uterus and testis protein (OUT) family; The OUT family includes transcription factor 23 (TCF-23), transcription factor 24 (TCF-24) and similar proteins. TCF-23, also termed Class A basic helix-loop-helix protein 24 (bHLHa24), is a bHLH transcription factor that is essential for progesterone-dependent decidualization. The mouse homolog is also called ovary, uterus and testis protein (OUT), which is expressed predominantly in the reproductive organs such as the uterus, ovary and testis. It shows an Id-like inhibitory activity and functions as a negative regulator of bHLH factors through the formation of a functionally inactive heterodimeric complex. OUT inhibits the formation of TCF3 and MYOD1 homodimers and heterodimers, but lacks DNA binding activity. OUT is involved in the regulation or modulation of smooth muscle contraction of the uterus during pregnancy and particularly around the time of delivery. It also plays a role in the inhibition of myogenesis. Unlike typical bHLH factors, OUT proteins do not bind E-box (CANNTG) or N-box DNA sequences and inhibit DNA binding of homo- and heterodimers consisting of E12 and MyoD in gel mobility shift assays. TCF-24 is an uncharacterized bHLH transcription factor that shows high sequence similarity with TCF-23.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1958660507 128 ARERNRMHDLNAALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 177
Cdd:cd11424     6 ARERSRVRTLRTAFQSLQRALPAVPPDTKLSKLDVLLLASRYIAHLTRKL 55

basic helix-loop-helix (bHLH) domain found in myogenin (MYOG) and similar proteins; MYOG, also termed Class C basic helix-loop-helix protein 3 (bHLHc3), or myogenic factor 4 (Myf-4), is a bHLH transcriptional activator that promotes transcription of muscle-specific target genes and plays a role in muscle differentiation, cell cycle exit and muscle atrophy.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1958660507 122 RRQKANARERNRMHDLNAALDNLRKVVpCYSKTQKLSKIETLRLAKNYIWALSEILRS 179
Cdd:cd18935     2 RRRAATLREKRRLKKVNEAFEALKRST-LLNPNQRLPKVEILRSAIQYIERLQALLSS 58

basic helix-loop-helix (bHLH) domain found in transcription factor 4 (TCF-4) and similar proteins; TCF-4, also termed E2-2, or Class B basic helix-loop-helix protein 19 (bHLHb19), or immunoglobulin transcription factor 2 (ITF-2), or SL3-3 enhancer factor 2 (SEF-2), is a bHLH transcription factor that binds to the immunoglobulin enhancer Mu-E5/KE5-motif. It is involved in the initiation of neuronal differentiation.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1958660507 115 RLERSKLRRQKANARERNRMHDLNAALDNLRKVVPCYSKTQK-LSKIETLRLAKNYIWALSEILR 178
Cdd:cd18945     1 KAEREKERRMANNARERLRVRDINEAFKELGRMVQLHLKSDKpQTKLLILHQAVAVILSLEQQVR 65