PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Arabis alpina
bHLH Family
Species TF ID Description
KFK21944.1bHLH family protein
KFK22396.1bHLH family protein
KFK23754.1bHLH family protein
KFK23906.1bHLH family protein
KFK24631.1bHLH family protein
KFK24862.1bHLH family protein
KFK25753.1bHLH family protein
KFK26541.1bHLH family protein
KFK26787.1bHLH family protein
KFK26940.1bHLH family protein
KFK27081.1bHLH family protein
KFK27270.1bHLH family protein
KFK27334.1bHLH family protein
KFK27804.1bHLH family protein
KFK27990.1bHLH family protein
KFK28233.1bHLH family protein
KFK28384.1bHLH family protein
KFK28388.1bHLH family protein
KFK28472.1bHLH family protein
KFK28692.1bHLH family protein
KFK28713.1bHLH family protein
KFK29420.1bHLH family protein
KFK29422.1bHLH family protein
KFK29423.1bHLH family protein
KFK29424.1bHLH family protein
KFK29425.1bHLH family protein
KFK29460.1bHLH family protein
KFK29682.1bHLH family protein
KFK30238.1bHLH family protein
KFK30277.1bHLH family protein
KFK30278.1bHLH family protein
KFK30312.1bHLH family protein
KFK30584.1bHLH family protein
KFK30585.1bHLH family protein
KFK30591.1bHLH family protein
KFK30627.1bHLH family protein
KFK30628.1bHLH family protein
KFK30669.1bHLH family protein
KFK31189.1bHLH family protein
KFK31230.1bHLH family protein
KFK31426.1bHLH family protein
KFK31432.1bHLH family protein
KFK31444.1bHLH family protein
KFK31544.1bHLH family protein
KFK32044.1bHLH family protein
KFK32082.1bHLH family protein
KFK32220.1bHLH family protein
KFK32340.1bHLH family protein
KFK32666.1bHLH family protein
KFK32795.1bHLH family protein
KFK33021.1bHLH family protein
KFK33185.1bHLH family protein
KFK33226.1bHLH family protein
KFK33352.1bHLH family protein
KFK33759.1bHLH family protein
KFK34072.1bHLH family protein
KFK34282.1bHLH family protein
KFK34607.1bHLH family protein
KFK34915.1bHLH family protein
KFK34930.1bHLH family protein
KFK35018.1bHLH family protein
KFK35066.1bHLH family protein
KFK35381.1bHLH family protein
KFK35883.1bHLH family protein
KFK36171.1bHLH family protein
KFK36676.1bHLH family protein
KFK36960.1bHLH family protein
KFK37059.1bHLH family protein
KFK37090.1bHLH family protein
KFK37155.1bHLH family protein
KFK37416.1bHLH family protein
KFK37445.1bHLH family protein
KFK37457.1bHLH family protein
KFK38048.1bHLH family protein
KFK38192.1bHLH family protein
KFK39275.1bHLH family protein
KFK39385.1bHLH family protein
KFK39507.1bHLH family protein
KFK39609.1bHLH family protein
KFK39667.1bHLH family protein
KFK40214.1bHLH family protein
KFK40384.1bHLH family protein
KFK40554.1bHLH family protein
KFK40679.1bHLH family protein
KFK41064.1bHLH family protein
KFK41238.1bHLH family protein
KFK41315.1bHLH family protein
KFK41327.1bHLH family protein
KFK41328.1bHLH family protein
KFK41329.1bHLH family protein
KFK41642.1bHLH family protein
KFK41823.1bHLH family protein
KFK41891.1bHLH family protein
KFK42197.1bHLH family protein
KFK42564.1bHLH family protein
KFK42664.1bHLH family protein
KFK42914.1bHLH family protein
KFK42944.1bHLH family protein
KFK43254.1bHLH family protein
KFK43307.1bHLH family protein
KFK43332.1bHLH family protein
KFK43521.1bHLH family protein
KFK43999.1bHLH family protein
KFK44344.1bHLH family protein
KFK44529.1bHLH family protein
KFK44530.1bHLH family protein
KFK44602.1bHLH family protein
KFK44657.1bHLH family protein
KFK44872.1bHLH family protein
KFK44896.1bHLH family protein
KFK45000.1bHLH 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