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.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1229750566 327 PPFKVRKEKLGDRIAALQQLVAPFGKTDTASVLMEAIGYIKFLQNQ 372
Cdd:cd11393     3 IAERKRREKINERIRALRSLVPNGGKTDKASILDEAIEYIKFLQEQ 48

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
                  ....*....|....*....|....*....|....*....|....*.
gi 1229750566 327 PPFKVRKEKLGDRIAALQQLVAPFGKTDTASVLMEAIGYIKFLQNQ 372
Cdd:cd11393     3 IAERKRREKINERIRALRSLVPNGGKTDKASILDEAIEYIKFLQEQ 48

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
                  ....*....|....*....|....*....|....*....|....*.
gi 1229750566 327 PPFKVRKEKLGDRIAALQQLVAPFGKTDTASVLMEAIGYIKFLQNQ 372
Cdd:cd11393     3 IAERKRREKINERIRALRSLVPNGGKTDKASILDEAIEYIKFLQEQ 48

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana phytochrome interacting factors (PIFs) and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as PIFs, ALC, PIL1, SPATULA, and UNE10. PIFs (PIF1, PIF3, PIF4, PIF5, PIF6 and PIF7) have been shown to control light-regulated gene expression. They directly bind to the photoactivated phytochromes and are degraded in response to light signals. ALC, also termed AtbHLH73, or protein ALCATRAZ, or EN 98, is required for the dehiscence of fruit, especially for the separation of the valve cells from the replum. It promotes the differentiation of a strip of labile non-lignified cells sandwiched between layers of lignified cells. PIL1, also termed AtbHLH124, or protein phytochrome interacting factor 3-like 1, or EN 110, is involved in responses to transient and long-term shade. It is required for the light-mediated inhibition of hypocotyl elongation and necessary for rapid light-induced expression of the photomorphogenesis- and circadian-related gene APRR9. PIL1 seems to play a role in multiple PHYB responses, such as flowering transition and petiole elongation. SPATULA, also termed AtbHLH24, or EN 99, plays a role in floral organogenesis. It promotes the growth of carpel margins and of pollen tract tissues derived from them. UNE10, also termed AtbHLH16, or protein UNFERTILIZED EMBRYO SAC 10, or EN 99, is required during the fertilization of ovules by pollen.

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                  ....*....|....*....|....*....|....*....|.
gi 1229750566 332 RKEKLGDRIAALQQLVAPFGKTDTASVLMEAIGYIKFLQNQ 372
Cdd:cd11445    13 RRDRINEKMKALQELIPNCNKTDKASMLDEAIEYLKSLQLQ 53

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana Fe-deficiency induced transcription factor 1 (FIT) and similar proteins; The family includes bHLH transcription factors from Arabidopsis thaliana, such as FIT and DYT1. FIT, also termed FER-like iron deficiency-induced transcription factor, or FER-like regulator of iron uptake, or AtbHLH29, or EN 43, is a bHLH transcription factor that is required for the iron deficiency response in plant. It regulates FRO2 at the level of mRNA accumulation and IRT1 at the level of protein accumulation. DYT1, also termed AtbHLH22, or protein dysfunctional tapetum 1, or EN 49, is a bHLH transcription factor involved in the control of tapetum development. It is required for male fertility and pollen differentiation, especially during callose deposition.

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                  ....*....|....*....|....*....|....*....|.
gi 1229750566 332 RKEKLGDRIAALQQLVAPFGKTDTASVLMEAIGYIKFLQNQ 372
Cdd:cd11450    14 RRQKLNQRLFALRSVVPNITKMDKASIIKDAISYIQELQYQ 54

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana BES1-interacting Myc-like proteins (BIMs) and similar proteins; The family includes Arabidopsis thaliana BIM1 and its homologs (BIM2 and BIM3), which are bHLH transcription factors that interact with BES1 to regulate transcription of Brassinosteroid (BR)-induced gene. BR regulates many growth and developmental processes such as cell elongation, vascular development, senescence stress responses, and photomorphogenesis. BIM1 heterodimerize with BES1 and bind to E-box sequences present in many BR-induced promoters to regulated BR-induced genes.

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                  ....*....|....*....|....*....|....*....|....*
gi 1229750566 332 RKEKLGDRIAALQQLVaPFG--KTDTASVLMEAIGYIKFLQNQTL 374
Cdd:cd11453    14 RRSKINERLQALRDLI-PHSdqKRDKASFLLEVIEYIQALQEKVA 57

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein ABA-INDUCIBLE bHLH-TYPE (AIB) and similar proteins; The family includes several bHLH transcription factors from Arabidopsis thaliana, such as AIB and MYC proteins (MYC2, MYC3 and MYC4). AIB, also termed AtbHLH17, or EN 35, is a transcription activator that regulates positively abscisic acid (ABA) response. MYC2, also termed protein jasmonate insensitive 1, or R-homologous Arabidopsis protein 1 (RAP-1), or AtbHLH6, or EN 38, or Z-box binding factor 1 protein, is a transcriptional activator involved in abscisic acid (ABA), jasmonic acid (JA), and light signaling pathways. MYC3, also termed protein altered tryptophan regulation 2, or AtbHLH5, or transcription factor ATR2, or EN 36, is a transcription factor involved in tryptophan, jasmonic acid (JA) and other stress-responsive gene regulation. MYC4, also termed AtbHLH4, or EN 37, is a transcription factor involved in jasmonic acid (JA) gene regulation. MYC2, together with MYC3 and MYC4, controls additively subsets of JA-dependent responses.

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                  ....*....|....*....|....*....|....*....|.
gi 1229750566 332 RKEKLGDRIAALQQLVAPFGKTDTASVLMEAIGYIKFLQNQ 372
Cdd:cd11449    16 RREKLNQRFYALRAVVPNVSKMDKASLLGDAISYINELKSK 56

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.

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                  ....*....|....*....|....*....|....*....|....
gi 1229750566 330 KVRKEKLGDRIAALQQLV---APFGKTDTASVLMEAIGYIKFLQ 370
Cdd:cd00083     2 RRRRDKINDAFEELKRLLpelPDSKKLSKASILQKAVEYIRELQ 45

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.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1229750566 332 RKEKLGDRIAALQQLVAPFGKTDTASVLMEAIGYIKFLQNQTLSVP 377
Cdd:cd11455    18 RRERINSHLATLRTLLPNLSKTDKASLLAEVVQHVKELKRQAAEIT 63

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.

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                  ....*....|....*....|....*....|....*....|.
gi 1229750566 332 RKEKLGDRIAALQQLVAPFGKTDTASVLMEAIGYIKFLQNQ 372
Cdd:cd18918     8 RREKLNEKFSDLRNLIPNPTKNDRASILSDAIKYINELQRT 48