PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Capsicum annuum
bHLH Family
Species TF ID Description
CA00g16330bHLH family protein
CA00g46850bHLH family protein
CA00g50270bHLH family protein
CA00g52210bHLH family protein
CA00g53720bHLH family protein
CA00g56330bHLH family protein
CA00g58390bHLH family protein
CA00g64360bHLH family protein
CA00g64680bHLH family protein
CA00g69000bHLH family protein
CA00g74140bHLH family protein
CA00g77770bHLH family protein
CA00g81450bHLH family protein
CA00g90280bHLH family protein
CA00g95620bHLH family protein
CA01g00280bHLH family protein
CA01g02540bHLH family protein
CA01g03980bHLH family protein
CA01g04070bHLH family protein
CA01g07140bHLH family protein
CA01g07270bHLH family protein
CA01g11010bHLH family protein
CA01g17310bHLH family protein
CA01g17540bHLH family protein
CA01g20090bHLH family protein
CA01g24820bHLH family protein
CA01g26770bHLH family protein
CA01g26780bHLH family protein
CA01g29420bHLH family protein
CA01g31490bHLH family protein
CA01g34700bHLH family protein
CA02g02540bHLH family protein
CA02g05210bHLH family protein
CA02g06560bHLH family protein
CA02g08580bHLH family protein
CA02g11990bHLH family protein
CA02g14270bHLH family protein
CA02g14320bHLH family protein
CA02g14440bHLH family protein
CA02g16250bHLH family protein
CA02g17470bHLH family protein
CA02g17520bHLH family protein
CA02g17720bHLH family protein
CA02g22090bHLH family protein
CA02g24210bHLH family protein
CA02g24420bHLH family protein
CA02g24530bHLH family protein
CA02g24540bHLH family protein
CA02g24550bHLH family protein
CA02g28360bHLH family protein
CA03g01440bHLH family protein
CA03g03520bHLH family protein
CA03g03750bHLH family protein
CA03g03880bHLH family protein
CA03g05590bHLH family protein
CA03g05960bHLH family protein
CA03g06220bHLH family protein
CA03g08260bHLH family protein
CA03g10970bHLH family protein
CA03g14140bHLH family protein
CA03g19200bHLH family protein
CA03g22700bHLH family protein
CA03g26850bHLH family protein
CA03g27670bHLH family protein
CA03g28940bHLH family protein
CA03g29570bHLH family protein
CA03g31220bHLH family protein
CA03g33540bHLH family protein
CA03g34690bHLH family protein
CA03g36090bHLH family protein
CA04g02940bHLH family protein
CA04g16130bHLH family protein
CA04g16920bHLH family protein
CA04g17180bHLH family protein
CA04g17900bHLH family protein
CA04g18460bHLH family protein
CA04g18570bHLH family protein
CA05g11860bHLH family protein
CA05g17200bHLH family protein
CA06g01960bHLH family protein
CA06g04950bHLH family protein
CA06g06440bHLH family protein
CA06g09750bHLH family protein
CA06g15210bHLH family protein
CA06g16490bHLH family protein
CA06g17570bHLH family protein
CA06g18230bHLH family protein
CA06g18640bHLH family protein
CA06g19080bHLH family protein
CA06g21040bHLH family protein
CA06g26450bHLH family protein
CA06g27810bHLH family protein
CA07g02200bHLH family protein
CA07g05870bHLH family protein
CA07g06670bHLH family protein
CA07g08480bHLH family protein
CA07g08980bHLH family protein
CA07g12500bHLH family protein
CA07g14840bHLH family protein
CA07g16720bHLH family protein
CA07g16740bHLH family protein
CA07g18840bHLH family protein
CA08g01690bHLH family protein
CA08g08700bHLH family protein
CA08g11740bHLH family protein
CA08g16840bHLH family protein
CA08g18860bHLH family protein
CA09g18370bHLH family protein
CA10g00130bHLH family protein
CA10g00260bHLH family protein
CA10g06410bHLH family protein
CA10g07410bHLH family protein
CA10g19940bHLH family protein
CA10g20700bHLH family protein
CA10g20710bHLH family protein
CA10g21780bHLH family protein
CA11g00840bHLH family protein
CA11g01590bHLH family protein
CA11g03130bHLH family protein
CA11g06150bHLH family protein
CA11g07790bHLH family protein
CA11g10800bHLH family protein
CA12g03230bHLH family protein
CA12g09670bHLH family protein
CA12g12200bHLH family protein
CA12g15610bHLH family protein
CA12g16720bHLH family protein
CA12g20410bHLH family protein
CA12g22470bHLH family protein
bHLH Family Introduction

The basic/helix-loop-helix (bHLH) proteins are a superfamily of transcription factors that have been well characterized in nonplant eukaryotes, especially in mammalian systems, in which considerable structural, functional, and phylogenetic analyses have been performed. The data indicate that bHLH proteins are important regulatory components in transcriptional networks in these systems, controlling a diversity of processes from cell proliferation to cell lineage establishment.

This family is defined by the bHLH signature domain, which consists of 60 amino acids with two functionally distinct regions. The basic region, located at the N-terminal end of the domain, is involved in DNA binding and consists of 15 amino acids with a high number of basic residues. The HLH region, at the C-terminal end, functions as a dimerization domain and is constituted mainly of hydrophobic residues that form two amphipathic -helices separated by a loop region of variable sequence and length. Outside of the conserved bHLH domain, these proteins exhibit considerable sequence divergence. Cocrystal structural analysis has shown that the interaction between the HLH regions of two separate polypeptides leads to the formation of homodimers and/or heterodimers and that the basic region of each partner binds to half of the DNA recognition sequence. Some bHLH proteins form homodimers or restrict their heterodimerization activity to closely related members of the family. On the other hand, some can form heterodimers with one or several different partners.

The core DNA sequence motif recognized by the bHLH proteins is a consensus hexanucleotide sequence known as the E-box (5'-CANNTG-3'). There are different types of E-boxes, depending on the identity of the two central bases. One of the most common is the palindromic G-box (5'-CACGTG-3'). Certain conserved amino acids within the basic region of the protein provide recognition of the core consensus site, whereas other residues in the domain dictate specificity for a given type of E-box . In addition, flanking nucleotides outside of the hexanucleotide core have been shown to play a role in binding specificity, and there is evidence that a loop residue in the protein plays a role in DNA binding through elements that lie outside of the core recognition sequence.

Toledo-Ortiz G, Huq E, Quail PH.
The Arabidopsis basic/helix-loop-helix transcription factor family.
Plant Cell. 2003 Aug;15(8):1749-70
PMID: 12897250