PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Genlisea aurea
bHLH Family
Species TF ID Description
EPS57409.1bHLH family protein
EPS57585.1bHLH family protein
EPS57632.1bHLH family protein
EPS57728.1bHLH family protein
EPS57820.1bHLH family protein
EPS57853.1bHLH family protein
EPS58336.1bHLH family protein
EPS58430.1bHLH family protein
EPS58961.1bHLH family protein
EPS59561.1bHLH family protein
EPS59766.1bHLH family protein
EPS59989.1bHLH family protein
EPS60825.1bHLH family protein
EPS60924.1bHLH family protein
EPS61442.1bHLH family protein
EPS61800.1bHLH family protein
EPS62318.1bHLH family protein
EPS62474.1bHLH family protein
EPS62617.1bHLH family protein
EPS62731.1bHLH family protein
EPS62866.1bHLH family protein
EPS62935.1bHLH family protein
EPS63404.1bHLH family protein
EPS63910.1bHLH family protein
EPS64228.1bHLH family protein
EPS64380.1bHLH family protein
EPS64516.1bHLH family protein
EPS64682.1bHLH family protein
EPS64790.1bHLH family protein
EPS65511.1bHLH family protein
EPS65759.1bHLH family protein
EPS65891.1bHLH family protein
EPS66017.1bHLH family protein
EPS66389.1bHLH family protein
EPS66403.1bHLH family protein
EPS66447.1bHLH family protein
EPS66593.1bHLH family protein
EPS66715.1bHLH family protein
EPS66915.1bHLH family protein
EPS67038.1bHLH family protein
EPS67081.1bHLH family protein
EPS67147.1bHLH family protein
EPS67384.1bHLH family protein
EPS67518.1bHLH family protein
EPS67626.1bHLH family protein
EPS67749.1bHLH family protein
EPS68093.1bHLH family protein
EPS68095.1bHLH family protein
EPS68274.1bHLH family protein
EPS68388.1bHLH family protein
EPS68391.1bHLH family protein
EPS68402.1bHLH family protein
EPS68800.1bHLH family protein
EPS69456.1bHLH family protein
EPS70109.1bHLH family protein
EPS70176.1bHLH family protein
EPS70314.1bHLH family protein
EPS70340.1bHLH family protein
EPS70400.1bHLH family protein
EPS70613.1bHLH family protein
EPS70639.1bHLH family protein
EPS70844.1bHLH family protein
EPS71023.1bHLH family protein
EPS71051.1bHLH family protein
EPS71427.1bHLH family protein
EPS71585.1bHLH family protein
EPS71706.1bHLH family protein
EPS72135.1bHLH family protein
EPS72555.1bHLH family protein
EPS72657.1bHLH family protein
EPS72893.1bHLH family protein
EPS73028.1bHLH family protein
EPS73774.1bHLH family protein
EPS73915.1bHLH family protein
EPS74146.1bHLH family protein
EPS74183.1bHLH family protein
EPS74199.1bHLH family protein
EPS74336.1bHLH family protein
EPS74560.1bHLH family protein
EPS74590.1bHLH 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