basic helix-loop-helix (bHLH) domain found in the spermatogenesis- and oogenesis-specific basic helix-loop-helix-containing protein (SOHLH) family; The SOHLH family includes two bHLH transcription factors, SOHLH1 and SOHLH2. They are specifically in spermatogonia and oocytes and essential for early spermatogonial and oocyte differentiation.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 158081743 202 SFLHSTKEKLRRERIKSCCEQLRTLLPYVKGRKSDVASVIEATVDYVKQVRESLSPA 258
Cdd:cd18908    3 ASSHSLKERLRRERIKSSCDQLRDLLPYIKGRKLDMASVLEMTVKYIRYIQERIPPE 59

basic helix-loop-helix (bHLH) domain found in the spermatogenesis- and oogenesis-specific basic helix-loop-helix-containing protein (SOHLH) family; The SOHLH family includes two bHLH transcription factors, SOHLH1 and SOHLH2. They are specifically in spermatogonia and oocytes and essential for early spermatogonial and oocyte differentiation.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 158081743 202 SFLHSTKEKLRRERIKSCCEQLRTLLPYVKGRKSDVASVIEATVDYVKQVRESLSPA 258
Cdd:cd18908    3 ASSHSLKERLRRERIKSSCDQLRDLLPYIKGRKLDMASVLEMTVKYIRYIQERIPPE 59

Helix-loop-helix DNA-binding domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 158081743  205 HSTKEKLRRERIKSCCEQLRTLLPYV-KGRKSDVASVIEATVDYVKQ 250
Cdd:pfam00010   5 HNERERRRRDRINDAFDELRELLPTLpPDKKLSKAEILRLAIEYIKH 51

basic helix-loop-helix (bHLH) domain found in the spermatogenesis- and oogenesis-specific basic helix-loop-helix-containing protein (SOHLH) family; The SOHLH family includes two bHLH transcription factors, SOHLH1 and SOHLH2. They are specifically in spermatogonia and oocytes and essential for early spermatogonial and oocyte differentiation.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 158081743 202 SFLHSTKEKLRRERIKSCCEQLRTLLPYVKGRKSDVASVIEATVDYVKQVRESLSPA 258
Cdd:cd18908    3 ASSHSLKERLRRERIKSSCDQLRDLLPYIKGRKLDMASVLEMTVKYIRYIQERIPPE 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 158081743 209 EKLRRERIKSCCEQLRTLLPYV-KGRKSDVASVIEATVDYVKQVRE 253
Cdd:cd00083    1 ERRRRDKINDAFEELKRLLPELpDSKKLSKASILQKAVEYIRELQS 46

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein maternal effect embryo arrest 8 (AtMEE8) and similar proteins; AtMEE8, also termed AtbHLH108, or EN 132, is a bHLH transcription factor required during early embryo development, for the endosperm formation.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 158081743 205 HSTKEKLRRERIKSCCEQLRTLLPYVKgRKSDVASVIEATVDYVKQVR---ESLSPAIM 260
Cdd:cd19698    1 HNLLEKKRRERIKDKIEILKGLTPNCT-PKSDIASILSCVIDYIKSLLlqvEKLSMGIC 58

basic helix-loop-helix-orange (bHLH-O) domain found in transcription factor HES-5 and similar proteins; HES-5, also termed Class B basic helix-loop-helix protein 38 (bHLHb38), or hairy and enhancer of split 5, is a bHLH-O transcription factor that is involved in cell differentiation and proliferation in a variety of tissues. HES-5 is an essential effector for Notch signaling. It acts as a transducer of Notch signals in brain vascular development. It also acts as a key mediator of Wnt-3a-induced neuronal differentiation and plays a crucial role in normal inner ear hair cell development. HES-5 is one mammalian counterpart of the Hairy and Enhancer of split proteins that play a critical role in many physiological processes including cellular differentiation, cell cycle arrest, apoptosis and self-renewal ability.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 158081743 209 EKLRRERIKSCCEQLRTLL--------PYVKGRKSDvasVIEATVDYVKQVRES 254
Cdd:cd11461    8 EKTRRDRINSSIEQLKTLLekefqrhqPNSKLEKAD---ILEMTVSFLKQSAKL 58

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein AIG1 and similar proteins; AIG1, also termed AtbHLH32, or EN 54, or protein target of MOOPTEROS 5, is a transcription factor required for MONOPTEROS-dependent root initiation in embryo.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 158081743 196 DKSKQASFLHSTKEKLRRERIKSCCEQLRTLLPyvKGRKSDVASVIEATVDYVKQVR 252
Cdd:cd11455    2 DKALAASKSHSEAERRRRERINSHLATLRTLLP--NLSKTDKASLLAEVVQHVKELK 56

basic helix-loop-helix-orange (bHLH-O) domain found in hairy and enhancer of split (HES)-related repressor protein (HERP)-like family; The HERP-like family includes bHLH-O transcriptional regulators that are related to the Drosophila hairy and Enhancer-of-split proteins. They contain a basic helix-loop-helix (bHLH) domain with an invariant glycine residue in its basic region, an orange domain in the central region and YXXW sequence motif at its C-terminal region. HERP proteins (HEY1, HEY2 and HEYL) act as downstream effectors of Notch signaling. They are involved in cardiovascular development and have roles in somitogenesis, myogenesis and gliogenesis. Hairy and enhancer of split-related protein HELT is a transcriptional repressor expressed in the developing central nervous system. It binds preferentially to the canonical E box sequence 5'-CACGCG-3' and regulates neuronal differentiation and/or identity. Differentially expressed in chondrocytes proteins, DEC1 and DEC2, are widely expressed in both embryonic and adult tissues and have been implicated in apoptosis, cell proliferation, and circadian rhythms, as well as malignancy in various cancers. Drosophila melanogaster protein clockwork orange (Cwo) is also included in this family. It is involved in the regulation of Drosophila circadian rhythms. It functions as both an activator and a repressor of clock gene expression.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 158081743 205 HSTKEKLRRERIKSCCEQLRTLLP----YVKGRKSDVASVIEATVDYVKQ 250
Cdd:cd11389    1 HKVIEKRRRDRINESLAELRRLVPearkSKGSGKLEKAEILEMTLQHLKA 50

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein IAA-leucine resistant 3 (ILR3) and similar proteins; ILR3, also termed AtbHLH105, or EN 133, is a bHLH transcription factor that plays a role in resistance to amide-linked indole-3-acetic acid (IAA) conjugates such as IAA-Leu and IAA-Phe. It may regulate gene expression in response to metal homeostasis changes.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 158081743 206 STKEKLRRERIKSCCEQLRTLLPYVKGRKSDVASVIEATVDYVKQVR 252
Cdd:cd11446    2 ACREKLRRDKLNERFMELSNVLEPGRPPKTDKATILGDAIRMLKQLR 48

basic helix-loop-helix (bHLH) domain found in transcription factor-like 5 protein (TCFL5) and similar proteins; TCFL5, also termed Cha transcription factor, or HPV-16 E2-binding protein 1 (E2BP-1), is a bHLH transcription factor that plays a crucial role in spermatogenesis. It regulates cell proliferation or differentiation of cells through binding to a specific DNA sequence like other bHLH molecules.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 158081743 205 HSTKEKLRRERIKSCCEQLRTLLPYVKGrKSDVASVIEATVDYVKQVRE 253
Cdd:cd18909    6 HNRMERDRRRRIRICCDELNLLVPFCNA-ETDKATTLQWTTAFLKYIQE 53

basic helix-loop-helix-orange (bHLH-O) domain found in Drosophila melanogaster enhancer of split mbeta protein (ESMB) and similar proteins; ESMB, also termed E(spl)mbeta, or HLH-mbeta, or split locus enhancer protein mA, is a bHLH-O transcriptional repressor of genes that require a bHLH protein for their transcription. It is involved in the neural-epidermal lineage decision during early neurogenesis. The family also includes Enhancer of split m7 protein (also known as E(spl)m7), which acts as a transcriptional repressor that participates in the control of cell fate choice by uncommitted neuroectodermal cells in the embryo.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 158081743 198 SKQASFLHSTK---EKLRRERIKSCCEQLRTLLPYVKGR------KSDVASVIEATVDYVKQVRES 254
Cdd:cd19741    2 SKTYQYRKVTKpllERKRRARINKCLDELKDLMVEALATeaenvsKLEKADILELTVRHLKKLRRQ 67

basic helix-loop-helix-orange (bHLH-O) domain found in HERP/HES-like family; The HERP/HES-like family includes bHLH-O transcriptional regulators that are related to the Drosophila hairy and Enhancer-of-split (HES) proteins. The HERP (HES-related repressor protein) subfamily proteins contain a basic helix-loop-helix (bHLH) domain with an invariant glycine residue in its basic region, an orange domain in the central region and YXXW sequence motif at its C-terminal region. Hairy and enhancer of split (HES)-related repressor protein (HERP) proteins (HEY1, HEY2 and HEYL) act as downstream effectors of Notch signaling. They are involved in cardiovascular development and have roles in somitogenesis, myogenesis and gliogenesis. Hairy and enhancer of split-related protein HELT is a transcriptional repressor expressed in the developing central nervous system. It binds preferentially to the canonical E box sequence 5'-CACGCG-3' and regulates neuronal differentiation and/or identity. Differentially expressed in chondrocytes proteins, DEC1 and DEC2, are widely expressed in both embryonic and adult tissues and have been implicated in apoptosis, cell proliferation, and circadian rhythms, as well as malignancy in various cancers. Drosophila melanogaster protein clockwork orange (Cwo) is also included in this subfamily. It is involved in the regulation of Drosophila circadian rhythms. It functions as both an activator and a repressor of clock gene expression. The HES subfamily proteins contain a basic helix-loop-helix (bHLH) domain with an invariant proline residue in its basic region, an orange domain in the central region and a conserved tetrapeptide motif, WRPW, at its C-terminal region. They form heterodimers or homodimers via their HLH domain and bind DNA to repress gene transcription that play an essential role in development of both compartment and boundary cells of the central nervous system.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 158081743 209 EKLRRERIKSCCEQLRTLLP----YVKGRKSDVASVIEATVDYVKQVR 252
Cdd:cd19685    2 EKRRRQRINDKLNQLKELLPpnlsKQSRSKLSKAEILEMAITELRRLQ 49

basic Helix-Loop-Helix (bHLH) domain found in Arabidopsis thaliana MYC1 and similar proteins; MYC1, also termed AtbHLH12, or EN 58, acts as a transcription activator, when associated with MYB75/PAP1 or MYB90/PAP2.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 158081743 205 HSTKEKLRRERIKSCCEQLRTLLPYVKgrKSDVASVIEATVDYVKQVR 252
Cdd:cd18918    1 LFATERERREKLNEKFSDLRNLIPNPT--KNDRASILSDAIKYINELQ 46

basic helix-loop-helix-orange (bHLH-O) domain found in hairy and enhancer of split (HES)-related repressor protein (HERP) family; HERP (also called Hey/Hesr/HRT/CHF/gridlock) proteins corresponds to a family of bHLH-O transcriptional repressors that are related to the Drosophila hairy and Enhancer-of-split proteins and act as downstream effectors of Notch signaling. They contain a basic helix-loop-helix (bHLH) domain with an invariant glycine residue in its basic region, an orange domain in the central region and YXXW sequence motif at its C-terminal region. HERP proteins are involved in cardiovascular development and have roles in somitogenesis, myogenesis and gliogenesis.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 158081743 209 EKLRRERIKSCCEQLRTLLP--YVK--GRKSDVASVIEATVDYVKQVR 252
Cdd:cd11407    9 EKRRRDRINNSLAELRRLVPtaFEKqgSAKLEKAEILQMTVDHLKMLH 56