PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Aethionema arabicum
bHLH Family
Species TF ID Description
AA102G00037bHLH family protein
AA102G00055bHLH family protein
AA102G00134bHLH family protein
AA112G00015bHLH family protein
AA123G00108bHLH family protein
AA123G00123bHLH family protein
AA12G00203bHLH family protein
AA13G00077bHLH family protein
AA150G00001bHLH family protein
AA167G00002bHLH family protein
AA17G00021bHLH family protein
AA17G00120bHLH family protein
AA18G00139bHLH family protein
AA1G00054bHLH family protein
AA21G00006bHLH family protein
AA21G00007bHLH family protein
AA21G00100bHLH family protein
AA21G00382bHLH family protein
AA21G00409bHLH family protein
AA21G00425bHLH family protein
AA21G00569bHLH family protein
AA221G00010bHLH family protein
AA22G00101bHLH family protein
AA23G00016bHLH family protein
AA25G00005bHLH family protein
AA26G00618bHLH family protein
AA26G00655bHLH family protein
AA26G00731bHLH family protein
AA26G00745bHLH family protein
AA26G00784bHLH family protein
AA273G00003bHLH family protein
AA27G00055bHLH family protein
AA29G00003bHLH family protein
AA29G00047bHLH family protein
AA29G00117bHLH family protein
AA2G00103bHLH family protein
AA2G00194bHLH family protein
AA30G00129bHLH family protein
AA30G00162bHLH family protein
AA30G00231bHLH family protein
AA30G00292bHLH family protein
AA30G00317bHLH family protein
AA31G00060bHLH family protein
AA31G00146bHLH family protein
AA31G00496bHLH family protein
AA31G00559bHLH family protein
AA32G00014bHLH family protein
AA32G00085bHLH family protein
AA32G00177bHLH family protein
AA32G00192bHLH family protein
AA32G00287bHLH family protein
AA32G00417bHLH family protein
AA32G00569bHLH family protein
AA32G00600bHLH family protein
AA32G00604bHLH family protein
AA32G00885bHLH family protein
AA32G01114bHLH family protein
AA33G00005bHLH family protein
AA33G00144bHLH family protein
AA33G00286bHLH family protein
AA351G00002bHLH family protein
AA39G00438bHLH family protein
AA39G00699bHLH family protein
AA3G00257bHLH family protein
AA40G00572bHLH family protein
AA42G00002bHLH family protein
AA44G00139bHLH family protein
AA44G00240bHLH family protein
AA44G00589bHLH family protein
AA44G00672bHLH family protein
AA44G00691bHLH family protein
AA45G00017bHLH family protein
AA46G00163bHLH family protein
AA4G00283bHLH family protein
AA50G00006bHLH family protein
AA53G00247bHLH family protein
AA53G00325bHLH family protein
AA53G00385bHLH family protein
AA53G00412bHLH family protein
AA53G00440bHLH family protein
AA53G00560bHLH family protein
AA53G00812bHLH family protein
AA53G00886bHLH family protein
AA53G01073bHLH family protein
AA53G01357bHLH family protein
AA53G01394bHLH family protein
AA54G00103bHLH family protein
AA55G00066bHLH family protein
AA56G00010bHLH family protein
AA56G00017bHLH family protein
AA57G00303bHLH family protein
AA57G00339bHLH family protein
AA57G00340bHLH family protein
AA5G00056bHLH family protein
AA5G00159bHLH family protein
AA5G00195bHLH family protein
AA61G00144bHLH family protein
AA61G00160bHLH family protein
AA61G00163bHLH family protein
AA61G00221bHLH family protein
AA61G00311bHLH family protein
AA61G00549bHLH family protein
AA61G00561bHLH family protein
AA65G00070bHLH family protein
AA65G00112bHLH family protein
AA65G00297bHLH family protein
AA6G00226bHLH family protein
AA6G00227bHLH family protein
AA76G00026bHLH family protein
AA77G00033bHLH family protein
AA78G00039bHLH family protein
AA78G00043bHLH family protein
AA7G00048bHLH family protein
AA7G00135bHLH family protein
AA7G00144bHLH family protein
AA87G00064bHLH family protein
AA87G00308bHLH family protein
AA8G00019bHLH family protein
AA8G00023bHLH family protein
AA93G00012bHLH family protein
AA96G00033bHLH family protein
AA9G00050bHLH family protein
AA9G00062bHLH family protein
AA9G00152bHLH family protein
AA9G00194bHLH 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