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 408359975 110 QQPAAVARRNERERNRVKLVNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEHDAVSAAFQ 180
Cdd:cd19742    1 QQPAAVARRNERERNRVKLVNMGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEHDAVSAAFQ 71

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 408359975 110 QQPAAVARRNERERNRVKLVNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEHDAVSAAFQ 180
Cdd:cd19742    1 QQPAAVARRNERERNRVKLVNMGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEHDAVSAAFQ 71

Helix-loop-helix DNA-binding domain;

                          10        20        30
                  ....*....|....*....|....*....|....*...
gi 408359975  129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQ 166
Cdd:pfam00010  16 INDAFDELRELLPTLPPDKKLSKAEILRLAIEYIKHLQ 53

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 408359975 110 QQPAAVARRNERERNRVKLVNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEHDAVSAAFQ 180
Cdd:cd19742    1 QQPAAVARRNERERNRVKLVNMGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEHDAVSAAFQ 71

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        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 408359975 113 AAVARRNERERNRVKLVNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEHDAV 175
Cdd:cd19743    2 AAVERRNERERNRVKLVNLGFAALRQHVPQGGASKKMSKVETLRSAVEYIRALQRLLGEHDAE 64

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
                 ....*....|....*....|....*....|....*....|....
gi 408359975 126 VKLVNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd11390   12 MHDLNDAFEALRKVLPTVPPDKKLSKIETLRLAINYIAALSDLL 55

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        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 408359975 111 QPAAVARRNERERNRVKLVNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLD 170
Cdd:cd19746    5 EPAFIRKRNERERQRVRCVNEGYARLREHLPQELADKRLSKVETLRAAIDYIKHLQELLE 64

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 408359975 114 AVARRNERERNRVKLVNLGFATLREHVP--------NGA---ANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd19744    1 SVARRNARERNRVKQVNNGFAILRQHIPqsviedltAGGgrgKSKKLSKVDTLRMAVEYIRRLQKLL 67

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 408359975 112 PAAVARRNERERNRVKLVNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd19745    2 PAFIRKRNERERQRVKCVNEGYAKLRRHLPQEYSEKRLSKVETLRAAIKYIKHLQSVL 59

Helix-loop-helix DNA-binding domain;

                          10        20        30
                  ....*....|....*....|....*....|....*...
gi 408359975  129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQ 166
Cdd:pfam00010  16 INDAFDELRELLPTLPPDKKLSKAEILRLAIEYIKHLQ 53

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
                 ....*....|....*....|....*....|....*....|.
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd11465   15 VNSAFTALRTLIPTEPADRKLSKIETLRLASSYISHLATVL 55

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
                 ....*....|....*....|....*....|....*....|....*
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEHD 173
Cdd:cd11471   16 INSAFAELRECIPNVPADTKLSKIKTLRLATSYIAYLMDLLAKDD 60

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
                 ....*....|....*....|....*....|....
gi 408359975 136 LREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd11427   22 LRKVVPCYSKTQKLSKIETLRLARNYIWALSEIL 55

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
                 ....*....|....*....|....*....|....*....|....*
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEHD 173
Cdd:cd19707   17 VNSAFAELRKLIPTHPPDKKLSKNEILRLAMKYINFLVKLLGDQG 61

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
                 ....*....|....*....|....*....|....*....|
gi 408359975 130 NLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd11430   17 NRAFDQLRSVVPSIGNDKKLSKYETLQMAQIYIETLSELL 56

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
                 ....*....|....*....|....*....|....*....|....
gi 408359975 129 VNLGFATLREHVP---NGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd11431   16 INDAFEALRRAVPeypVAGKDGKLTKITTLRLAMNYIKALTDLL 59

basic helix-loop-helix (bHLH) domain found in Drosophila melanogaster myogenic-determination protein (dMYOD) and similar proteins; dMYOD, also termed protein nautilus, or Myd, may play an important role in the early development of muscle in Drosophila.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 408359975 126 VKLVNLGFATLREHVPNGAaNKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd19699   14 LRKVNEAFEVLKRRTCPNP-NQRLPKVEILRNAIEYIESLEDLL 56

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
                 ....*....|....*....|....*....|....*....|....*
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEHD 173
Cdd:cd19706   19 VNGAFAELRKLIPTHPPDKKLSKNEILRLAMKYINFLAKLLNDQE 63

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
                 ....*....|....*....|....*....|....*....|....*....|..
gi 408359975 133 FATLREHVPNGAANKKMSKVETLRSAVEYIRALQ----QLLDEHDAVSAAFQ 180
Cdd:cd11456   24 FLTLRDHVPELVKNEKAAKVVILKKATEYVHSLQaeeqKLLLEKEKLQARQQ 75

basic helix-loop-helix (bHLH) domain found in DNA-binding protein inhibitor ID2 and similar proteins; ID2, also termed Class B basic helix-loop-helix protein 26 (bHLHb26), or inhibitor of DNA binding 2, or inhibitor of differentiation 2, 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 has been implicated in the regulation of cell proliferation and differentiation in myogenesis, neurogenesis, and/or hematopoiesis.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEH 172
Cdd:cd19692   22 MNDCYSKLKELVPSIPQNKKVSKMEILQHVIDYILDLQIALDSH 65

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
                 ....*....|....*....|....*....|....*..
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRAL 165
Cdd:cd19711   16 LNNAFQALREVIPHVRAEKKLSKIETLTLAKNYIKSL 52

basic helix-loop-helix (bHLH) domain found in DNA-binding protein inhibitor ID1 and similar proteins; ID1, also termed Class B basic helix-loop-helix protein 24 (bHLHb24), or inhibitor of DNA binding 1, or inhibitor of differentiation 1, 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. ID1 interferes with centrosomal function. It has been implicated in the regulation of cell proliferation and differentiation in myogenesis, neurogenesis, and/or hematopoiesis.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|
gi 408359975 133 FATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDEH 172
Cdd:cd19691   12 YSRLKELVPTLPQNRKVSKVEILQHVIDYIWDLQVELDSG 51

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
                 ....*....|....*....|....*....|....*....|.
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd11416   20 INSAFEELRCHVPTFPYEKRLSKIDTLRLAIAYIALLRDIL 60

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
                 ....*....|....*....|....*....|....*....|....*
gi 408359975 126 VKLVNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLD 170
Cdd:cd19702   28 VEAFNLAFAELRKLLPTLPPDKKLSKIEILRLAICYISYLNHVLD 72

basic helix-loop-helix (bHLH) domain found in the DNA-binding protein inhibitor (ID) family; The ID family includes a dominant negative group of helix-loop-helix (dnHLH) proteins, ID1-4, that are negative regulators of bHLH transcription factors. They contain the HLH-dimerization domain but lack the basic domain necessary for DNA-binding. ID proteins inhibit binding to DNA and transcriptional transactivation by heterodimerization with bHLH proteins. They also interact with many non-bHLH proteins in complex networks. ID proteins have been implicated in regulating gene expression as well as cell-cycle progression. Whereas ID-1, ID-2 and ID-3, are generally considered as tumor promoters, ID4 on the contrary has emerged as a tumor suppressor.

                         10        20        30
                 ....*....|....*....|....*....|....
gi 408359975 133 FATLREHVPNGAANKKMSKVETLRSAVEYIRALQ 166
Cdd:cd19684   12 YSKLKELVPTIPQNKKVSKVEILQHVIDYILDLQ 45

basic helix-loop-helix (bHLH) domain found in 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. The family also includes mesogenin-1 (Msgn1) and similar proteins. Msgn1, also termed paraxial mesoderm-specific mesogenin1, or pMesogenin1 (pMsgn1), is a bHLH transcription factor required for maturation and segmentation of paraxial mesoderm. It may regulate the expression of T-box transcription factors essential for mesoderm formation and differentiation.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|
gi 408359975 132 GFATLREHVPNGAA--NKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd11425   19 ALGELRQHLPPSVApkGKRLSKIQTLKYAIRYIGYLGNVL 58

basic helix-loop-helix (bHLH) domain found in myogenic factor 5 (Myf-5) and similar proteins; Myf-5, also termed Class C basic helix-loop-helix protein 2 (bHLHc2), is a nuclear bHLH transcriptional activator that promotes transcription of muscle-specific target genes and plays a role in muscle specification and differentiation. It also acts as an RNA-binding protein which enhances Ccnd1/Cyclin D1 mRNA translation during myogenesis.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 408359975 126 VKLVNLGFATLREhVPNGAANKKMSKVETLRSAVEYIRALQQLLDEH 172
Cdd:cd18937   14 LKKVNQAFETLKR-CTTSNPNQRLPKVEILRNAIRYIESLQDLLREQ 59

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
                 ....*....|....*....|....*....|....*....|.
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd19722   29 LNDALDSLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 69

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
                 ....*....|....*....|....*....|....*
gi 408359975 136 LREHVPNGAANKKMSKVETLRSAVEYIRALQQLLD 170
Cdd:cd11428   23 LREVLPSFPDETKLTKIETLRFAHNYIWALSETLK 57

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
                 ....*....|....*....|....*....|....*..
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRAL 165
Cdd:cd19712   16 LNDAFQGLREVIPHVNAERKLSKIETLTLAKNYIKAL 52

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
                 ....*....|....*....|....*....|....*....|.
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd18951   19 VNTAFTALRTLIPTEPADRKLSKIETLRLASSYISHLGNVL 59

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
                 ....*....|....*....|....*....|....*....|.
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd19713   21 LNHAFDQLRNVIPSFNNDKKLSKYETLQMAQIYINALSELL 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
                 ....*....|....*....|....*....|....*....|.
gi 408359975 129 VNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd19720   50 LNSALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 90

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in Max-binding protein Mnt and similar proteins; Mnt, also termed Class D basic helix-loop-helix protein 3 (bHLHd3), or Myc antagonist MNT, or protein ROX, is a bHLHZip transcriptional repressor that binds DNA as a heterodimer with MAX. It binds to the canonical E box sequence 5'-CACGTG-3' and, with higher affinity, to 5'-CACGCG-3'. Mnt has an important role as an antagonist and regulator of Myc activities and it is a potential tumor suppressor. Mnt is ubiquitously expressed. Mnt-deficient mice shown to exhibit early postnatal lethality.

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                 ....*....|....*....|....*....|....*....|..
gi 408359975 133 FATLREHVPNGAaNKKMSKVETLRSAVEYIRALQQLLDEHDA 174
Cdd:cd11402   21 FETLKRQIPNLD-DKKTSNLNILRSALRYIQILKRKEKEYEH 61

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
                 ....*....|....*....|....*....|....*....|....*
gi 408359975 126 VKLVNLGFATL-REHVPNgaANKKMSKVETLRSAVEYIRALQQLL 169
Cdd:cd18935   14 LKKVNEAFEALkRSTLLN--PNQRLPKVEILRSAIQYIERLQALL 56

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 408359975 129 VNLGFATLREHVPNGAA--NKKMSKVETLRSAVEYIRALQQ 167
Cdd:cd11405   18 IKSGFDTLQSLIPSLGQnpNQKVSKAAMLQKAAEYIKSLKR 58

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
                 ....*....|....*....|....*....|....*....|....*.
gi 408359975 131 LGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQllDEHDAVS 176
Cdd:cd11458   22 LSFFALRDQIPEVANNEKAPKVVILKKATEYILSMQA--DEQRLIS 65

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
                 ....*....|....*....|....*....|....*....|....*.
gi 408359975 126 VKLVNLGFATLREHVPNGAANKKMSKVETLRSAVEYIRALQQLLDE 171
Cdd:cd19703   16 MRVLSKAFSRLKTSLPWVPPDTKLSKLDTLRLASSYIAHLRQLLQE 61

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
                 ....*....|....*....|....*....|....*....|....*....|....
gi 408359975 129 VNLGFATLREHVP---------------NGAANKKMSKVETLRSAVEYIRALQQ 167
Cdd:cd11395   18 LNTKIERLRDAIPslrspegksddgglgGLAPTTKLSKATILTKAIEYIRHLEQ 71

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
                 ....*....|....*....|....*....|....*....|.
gi 408359975 129 VNLGFATLREHVPNGAANKkMSKVETLRSAVEYIRALQQLL 169
Cdd:cd11464   16 LNEAFTSLRKIIPTLPSDK-LSKIQTLKLAARYIDFLYQVL 55

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
                 ....*....|....*....|....*....|....*....|....
gi 408359975 130 NLGFATLREHVP--NGAANKKMSKVETLRSAVEYIRALQQLLDE 171
Cdd:cd11429   16 NSALDGLRSVMPyaQGPSVRKLSKIATLLLARNYILMLTQALEE 59