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        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907129176 561 KAEREKERRMANNARERLRVRDINEAFKELGRMVQLHLKSDKPQTKLLILHQAVAVILSLEQQVRERNLNPKAACLKRRE 640
Cdd:cd18945     1 KAEREKERRMANNARERLRVRDINEAFKELGRMVQLHLKSDKPQTKLLILHQAVAVILSLEQQVRERNLNPKAACLKRRE 80

                  ....*
gi 1907129176 641 EEKVS 645
Cdd:cd18945    81 EEKVS 85

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        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907129176 561 KAEREKERRMANNARERLRVRDINEAFKELGRMVQLHLKSDKPQTKLLILHQAVAVILSLEQQVRERNLNPKAACLKRRE 640
Cdd:cd18945     1 KAEREKERRMANNARERLRVRDINEAFKELGRMVQLHLKSDKPQTKLLILHQAVAVILSLEQQVRERNLNPKAACLKRRE 80

                  ....*
gi 1907129176 641 EEKVS 645
Cdd:cd18945    81 EEKVS 85

Helix-loop-helix DNA-binding domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1907129176 568 RRMANNARERLRVRDINEAFKELGRMVQlHLKSDKPQTKLLILHQAVAVILSLE 621
Cdd:pfam00010   1 RREAHNERERRRRDRINDAFDELRELLP-TLPPDKKLSKAEILRLAIEYIKHLQ 53

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        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907129176 561 KAEREKERRMANNARERLRVRDINEAFKELGRMVQLHLKSDKPQTKLLILHQAVAVILSLEQQVRERNLNPKAACLKRRE 640
Cdd:cd18945     1 KAEREKERRMANNARERLRVRDINEAFKELGRMVQLHLKSDKPQTKLLILHQAVAVILSLEQQVRERNLNPKAACLKRRE 80

                  ....*
gi 1907129176 641 EEKVS 645
Cdd:cd18945    81 EEKVS 85

basic helix-loop-helix (bHLH) domain found in transcription factor 12 (TCF-12) and similar proteins; TCF-12, also termed HEB, or Class B basic helix-loop-helix protein 20 (bHLHb20), or DNA-binding protein HTF4, or E-box-binding protein, or transcription factor HTF-4, is a bHLH transcription factor that is involved in the initiation of neuronal differentiation.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1907129176 568 RRMANNARERLRVRDINEAFKELGRMVQLHLKSDKPQTKLLILHQAVAVILSLEQQVRERNLNPKAACLKRREEEKVSS 646
Cdd:cd18946     1 RRMANNARERLRVRDINEAFKELGRMCQLHLKSEKPQTKLLILHQAVAVILSLEQQVRERNLNPKAACLKRREEEKVSA 79

basic helix-loop-helix (bHLH) domain found in Drosophila melanogaster protein daughterless (Da) and similar proteins; Da is a nuclear bHLH transcription factor that is a sole E protein ortholog essential for both neurogenesis and sex determination in Drosophila. Da is expressed in a broad range of tissues and is involved in diverse developmental processes such as oogenesis, sex determination and neurogenesis depending on its bHLH-binding partners. Da and achaete-scute complex (AS-C) form heterodimers that act as transcriptional activators of neural cell fates and are involved in sex determination.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907129176 567 ERRMANNARERLRVRDINEAFKELGRMVQLHLKSDKPQTKLLILHQAVAVILSLEQQVRERNLNPKAACL 636
Cdd:cd11467     1 ERRQANNARERIRIRDINEALKELGRMCMTHLKSDKPQTKLGILNMAVEVIMTLEQQVRERNLNPKAACL 70

helix loop helix domain;

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....
gi 1907129176  573 NARERLRVRDINEAFKELGRMVQLHLKSDKPqTKLLILHQAVAVILSLEQQVRE 626
Cdd:smart00353   1 NARERRRRRKINEAFDELRSLLPTLPKNKKL-SKAEILRLAIEYIKSLQEELQK 53

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1907129176 569 RMANNARERLRVRDINEAFKELgRMVQLHLKSDKPQTKLLILHQAVAVILSLEQ 622
Cdd:cd11390     1 RNAANARERRRMHDLNDAFEAL-RKVLPTVPPDKKLSKIETLRLAINYIAALSD 53

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 1907129176 568 RRMANnARERLRVRDINEAFKELGRMVQLHLKSDKPqTKLLILHQAVAVILSLEQ 622
Cdd:cd11422     1 RRVAN-ARERERVRNLNSGFSKLRRIVPLIPRDRKP-SKVDTLKGATEYIRLLQR 53

basic helix-loop-helix (bHLH) domain found in Class A basic helix-loop-helix protein 9 (bHLHa9) and similar proteins; bHLHa9, also termed Class F basic helix-loop-helix factor 42 (bHLHf42), is a bHLH transcription factor that plays an essential role in limb development.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1907129176 564 REKERRMANNARERLRVRDINEAFKELgRMVQLHLKSDKPQTKLLILHQAVAVILSL 620
Cdd:cd18912     4 RSKARRVAANVRERKRILDYNQAFNAL-RLALKHDLGGKRLSKIATLRRAINRISAL 59

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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1907129176 566 KERRMANNARERLRVRDINEAFKELgRMVQLHLKSDKpQTKLLILHQAVAVILSLEQQVRE 626
Cdd:cd11419     2 RIRREIANSNERRRMQSINAGFQSL-RTLLPHCDGEK-LSKAAILQQTAEYIFSLEQEKTR 60

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 1907129176 566 KERRmanNARERLRVRDINEAFKELGRMVQlHLKSDKPQTKLLILHQAVAVILSLEQQ 623
Cdd:cd11418     2 VARR---NERERRRVQAVNDAFDRLRQHVP-YLKRRKKLSKVKTLRRAIEYIRHLQKL 55

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 1907129176 565 EKERRMANNARERLRVRDINEAFKELgRMVQLHLKSDKPQTKLLILHQAVAVILSLEQ 622
Cdd:cd19713     3 QKQRRLAANARERRRMHGLNHAFDQL-RNVIPSFNNDKKLSKYETLQMAQIYINALSE 59

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 1907129176 568 RRMANNARERLRVRDINEAFKELGRMVQLHlKSDKPQTKLLILHQAVAVILSLEQQVR 625
Cdd:cd19708     1 RRMFTNSRERWRQQNVNGAFAELRKLVPTH-PPDKKLSKNEILRLAIKYIRLLSNVLE 57

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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1907129176 557 TPEQKAEREKERRMANNARERLRVRDINEAFKELGRMVQLHLKSDKpQTKLLILHQAVAVILSLEQQVR 625
Cdd:cd19722     3 MTKARMERVKVRRQEANARERNRMHGLNDALDSLRKVVPCYSKTQK-LSKIETLRLAKNYIWALSEILR 70

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 1907129176 568 RRMANNARERLRVRDINEAFKELgRMVQLHLKSDKPQTKLLILHQAVAVILSL 620
Cdd:cd19711     1 RRLESNERERQRMHKLNNAFQAL-REVIPHVRAEKKLSKIETLTLAKNYIKSL 52

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 1907129176 566 KERRMANNARERLRVRDINEAFKELgRMVQLHLKSDKPQTKLLILHQAVAVILSL 620
Cdd:cd19715     6 KKRRLAANARERRRMNSLNVAFDKL-RDVVPSLGDDRKLSKYETLQMAQSYITAL 59

basic helix-loop-helix (bHLH) domain found in T-cell acute lymphocytic leukemia protein/ lymphoblastic leukemia-derived sequence (TAL/LYL) family; The TAL/LYL family includes a group of bHLH transcription factors (TAL1, TAL2 and LYL1) implicated in T cell acute leukaemia. They act as mediators of T cell leukaemogenesis. 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-2, also termed Class A basic helix-loop-helix protein 19 (bHLHa19), is a bHLH transcription factor essential for the normal brain development. 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 that 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 1907129176 568 RRMANNARERLRVRDINEAFKELGRMVQLHlKSDKPQTKLLILHQAVAVILSLE 621
Cdd:cd11413     1 RRIFTNTRERWRQQNVNGAFAELRKLIPTH-PPDKKLSKNEILRLAMKYIKFLE 53

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 1907129176 568 RRMANNARERLRVRDINEAFKELGRMVQLHlKSDKPQTKLLILHQAVAVI 617
Cdd:cd19707     2 RKIFTNTRERWRQQNVNSAFAELRKLIPTH-PPDKKLSKNEILRLAMKYI 50

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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907129176 568 RRMANNARERLRVRDINEAFKELGRMVQLHlKSDKPQTKLLILHQAVAVILSLEQQVRER 627
Cdd:cd19705     6 RRVFTNSRERWRQQNVNGAFAELRKLIPTH-PPDKKLSKNEILRLAMKYIDFLVTLLRDQ 64

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1907129176 572 NNARERLRVRDINEAFKELGRMVQLHLKSDkpqtKLLILHQAVAVILSLEQQVRE 626
Cdd:cd11393     1 HSIAERKRREKINERIRALRSLVPNGGKTD----KASILDEAIEYIKFLQEQVKV 51

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
                  ....*....|....*....|....*....|....*....|....*....|
gi 1907129176 568 RRMANNARERLRVRDINEAFKELGRMVQLHlKSDKPQTKLLILHQAVAVI 617
Cdd:cd19706     4 RRIFTNSRERWRQQNVNGAFAELRKLIPTH-PPDKKLSKNEILRLAMKYI 52

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        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907129176 552 DDEDLTPEQKA-----------EREKERRMANNARERLRVRDINEAFKELGRMVQLHLKSDKpQTKLLILHQAVAVILSL 620
Cdd:cd19719     1 EDDDQKPKRRGpkkkkmtkarlERFKMRRMKANARERNRMHGLNAALDNLRKVVPCYSKTQK-LSKIETLRLAKNYIWAL 79

                  ....*
gi 1907129176 621 EQQVR 625
Cdd:cd19719    80 SEILR 84

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in MAX gene-associated protein (MGA) family; The MGA family includes MGA, Schizosaccharomyces pombe ESC1 (spESC1) and similar proteins. MGA, also termed MAX dimerization protein 5 (MAD5), is a dual specificity T-box/ bHLHzip transcription factor that regulates the expression of both Max-network and T-box family target genes. It contains a Myc-like bHLHZip motif and requires heterodimerization with Max for binding to the preferred Myc-Max-binding site CACGTG. In addition to the bHLHZip domain, MGA harbors a second DNA-binding domain, the T-box or T-domain. It thus binds the preferred Brachyury-binding sequence and represses transcription of reporter genes containing promoter-proximal Brachyury-binding sites. spESC1 is a bHLHzip protein with homology to human MyoD and Myf-5 myogenic differentiation inducers. It is involved in the sexual differentiation process.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1907129176 569 RMANNARERLRVRDINEAFKELgrMVQLHLKSDKPQTKLLILHQAVAVILSLEQQ 623
Cdd:cd19682     1 RLRHKKRERERRSELRELFDKL--KQLLGLDSDEKASKLAVLTEAIEEIQQLKRE 53

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 1907129176 568 RRMANNARERLRVRDINEAFKELgRMVQLHLKSDKPQTKLLILHQAVAVILSLEQQVR 625
Cdd:cd11428     1 RRLKANDRERNRMHNLNDALDAL-REVLPSFPDETKLTKIETLRFAHNYIWALSETLK 57

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 1907129176 573 NARERLRVRDINEAFKELGRMVQLHLKsDKPQTKLLILHQAVAVILSLEQQ 623
Cdd:cd19724     6 NERERQRVRCVNEGYARLRRHLPLENK-DKRLSKVETLRAAIRYIKHLQEL 55