PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Populus euphratica
bHLH Family
Species TF ID Description
CCG000075.1bHLH family protein
CCG000223.2bHLH family protein
CCG000557.1bHLH family protein
CCG000564.1bHLH family protein
CCG000588.1bHLH family protein
CCG001062.1bHLH family protein
CCG001161.1bHLH family protein
CCG001259.1bHLH family protein
CCG001493.1bHLH family protein
CCG001517.1bHLH family protein
CCG001610.2bHLH family protein
CCG001791.1bHLH family protein
CCG002083.1bHLH family protein
CCG002218.1bHLH family protein
CCG002297.2bHLH family protein
CCG002572.1bHLH family protein
CCG002630.1bHLH family protein
CCG002721.2bHLH family protein
CCG003376.1bHLH family protein
CCG003952.1bHLH family protein
CCG003977.1bHLH family protein
CCG004347.1bHLH family protein
CCG004564.1bHLH family protein
CCG004583.1bHLH family protein
CCG005639.1bHLH family protein
CCG005828.1bHLH family protein
CCG005959.1bHLH family protein
CCG006492.1bHLH family protein
CCG006663.1bHLH family protein
CCG007165.1bHLH family protein
CCG007427.1bHLH family protein
CCG007576.1bHLH family protein
CCG007789.1bHLH family protein
CCG007824.1bHLH family protein
CCG007912.1bHLH family protein
CCG007925.1bHLH family protein
CCG008342.1bHLH family protein
CCG008415.1bHLH family protein
CCG008436.1bHLH family protein
CCG008622.1bHLH family protein
CCG008652.2bHLH family protein
CCG009208.1bHLH family protein
CCG009265.1bHLH family protein
CCG010244.2bHLH family protein
CCG010245.1bHLH family protein
CCG010255.1bHLH family protein
CCG010529.1bHLH family protein
CCG010807.1bHLH family protein
CCG010847.1bHLH family protein
CCG010869.1bHLH family protein
CCG010909.1bHLH family protein
CCG011165.1bHLH family protein
CCG011166.1bHLH family protein
CCG011167.1bHLH family protein
CCG011311.2bHLH family protein
CCG011314.1bHLH family protein
CCG011315.1bHLH family protein
CCG011365.2bHLH family protein
CCG012004.1bHLH family protein
CCG012079.1bHLH family protein
CCG012101.1bHLH family protein
CCG012190.1bHLH family protein
CCG012310.1bHLH family protein
CCG012388.1bHLH family protein
CCG012955.1bHLH family protein
CCG013099.1bHLH family protein
CCG013244.1bHLH family protein
CCG013253.3bHLH family protein
CCG014012.1bHLH family protein
CCG014017.1bHLH family protein
CCG014033.1bHLH family protein
CCG014239.1bHLH family protein
CCG014442.1bHLH family protein
CCG014454.1bHLH family protein
CCG014703.2bHLH family protein
CCG015339.1bHLH family protein
CCG015724.1bHLH family protein
CCG015838.1bHLH family protein
CCG015907.1bHLH family protein
CCG016056.1bHLH family protein
CCG016545.1bHLH family protein
CCG017162.1bHLH family protein
CCG017221.2bHLH family protein
CCG017317.1bHLH family protein
CCG017558.1bHLH family protein
CCG017618.1bHLH family protein
CCG017754.1bHLH family protein
CCG017779.1bHLH family protein
CCG017859.1bHLH family protein
CCG017869.1bHLH family protein
CCG017998.1bHLH family protein
CCG018234.1bHLH family protein
CCG018235.1bHLH family protein
CCG018236.2bHLH family protein
CCG018237.1bHLH family protein
CCG018438.1bHLH family protein
CCG018612.1bHLH family protein
CCG018920.1bHLH family protein
CCG018959.1bHLH family protein
CCG019068.1bHLH family protein
CCG019360.1bHLH family protein
CCG019557.1bHLH family protein
CCG019618.1bHLH family protein
CCG019679.1bHLH family protein
CCG019730.1bHLH family protein
CCG019770.1bHLH family protein
CCG019840.1bHLH family protein
CCG020038.1bHLH family protein
CCG020127.1bHLH family protein
CCG020429.1bHLH family protein
CCG020621.1bHLH family protein
CCG020759.1bHLH family protein
CCG021155.1bHLH family protein
CCG021177.1bHLH family protein
CCG021554.1bHLH family protein
CCG021565.1bHLH family protein
CCG021655.1bHLH family protein
CCG021831.1bHLH family protein
CCG022273.1bHLH family protein
CCG022614.1bHLH family protein
CCG022623.1bHLH family protein
CCG022793.1bHLH family protein
CCG022996.1bHLH family protein
CCG023066.1bHLH family protein
CCG023265.1bHLH family protein
CCG023532.1bHLH family protein
CCG023655.1bHLH family protein
CCG023931.1bHLH family protein
CCG024415.1bHLH family protein
CCG024505.1bHLH family protein
CCG024785.1bHLH family protein
CCG024796.1bHLH family protein
CCG025128.1bHLH family protein
CCG025175.2bHLH family protein
CCG025188.1bHLH family protein
CCG026522.1bHLH family protein
CCG026575.1bHLH family protein
CCG026846.1bHLH family protein
CCG027047.3bHLH family protein
CCG027089.1bHLH family protein
CCG027357.1bHLH family protein
CCG027402.1bHLH family protein
CCG027404.1bHLH family protein
CCG027405.1bHLH family protein
CCG027553.1bHLH family protein
CCG027609.1bHLH family protein
CCG027666.1bHLH family protein
CCG027701.1bHLH family protein
CCG027755.1bHLH family protein
CCG027761.1bHLH family protein
CCG027920.1bHLH family protein
CCG028110.1bHLH family protein
CCG028287.1bHLH family protein
CCG028681.2bHLH family protein
CCG028867.1bHLH family protein
CCG029417.2bHLH family protein
CCG029625.1bHLH family protein
CCG029773.1bHLH family protein
CCG029930.1bHLH family protein
CCG030221.2bHLH family protein
CCG030366.1bHLH family protein
CCG030604.1bHLH family protein
CCG030855.1bHLH family protein
CCG030899.1bHLH family protein
CCG031204.1bHLH family protein
CCG031213.1bHLH family protein
CCG031585.1bHLH family protein
CCG031933.1bHLH family protein
CCG032123.1bHLH family protein
CCG032214.1bHLH family protein
CCG033096.1bHLH family protein
CCG033103.1bHLH family protein
CCG033207.1bHLH family protein
CCG033618.1bHLH family protein
CCG033813.1bHLH family protein
CCG033835.1bHLH family protein
CCG033938.1bHLH family protein
CCG034191.1bHLH 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