Plant Transcription Factor Database
Previous version: v3.0
Fragaria x ananassa
bHLH Family
Species TF ID Description
FANhyb_icon00001650_a.1.g00001.1bHLH family protein
FANhyb_icon00001738_a.1.g00001.1bHLH family protein
FANhyb_icon00001839_a.1.g00001.1bHLH family protein
FANhyb_icon00003056_a.1.g00001.1bHLH family protein
FANhyb_icon00003699_a.1.g00001.1bHLH family protein
FANhyb_icon00005720_a.1.g00001.1bHLH family protein
FANhyb_icon00005989_a.1.g00001.1bHLH family protein
FANhyb_icon00006028_a.1.g00001.1bHLH family protein
FANhyb_icon00006341_a.1.g00001.1bHLH family protein
FANhyb_icon00013202_a.1.g00001.1bHLH family protein
FANhyb_icon00014569_a.1.g00001.1bHLH family protein
FANhyb_icon00015098_a.1.g00001.1bHLH family protein
FANhyb_icon00017764_a.1.g00001.1bHLH family protein
FANhyb_icon00020217_a.1.g00001.1bHLH family protein
FANhyb_icon00020780_a.1.g00001.1bHLH family protein
FANhyb_icon00020838_a.1.g00001.1bHLH family protein
FANhyb_icon00022263_a.1.g00001.1bHLH family protein
FANhyb_icon00043757_a.1.g00001.1bHLH family protein
FANhyb_icon00059902_a.1.g00001.1bHLH family protein
FANhyb_rscf00000006.1.g00024.1bHLH family protein
FANhyb_rscf00000007.1.g00021.1bHLH family protein
FANhyb_rscf00000010.1.g00030.1bHLH family protein
FANhyb_rscf00000013.1.g00009.1bHLH family protein
FANhyb_rscf00000026.1.g00008.1bHLH family protein
FANhyb_rscf00000032.1.g00007.1bHLH family protein
FANhyb_rscf00000033.1.g00028.1bHLH family protein
FANhyb_rscf00000043.1.g00015.1bHLH family protein
FANhyb_rscf00000052.1.g00005.1bHLH family protein
FANhyb_rscf00000063.1.g00022.1bHLH family protein
FANhyb_rscf00000091.1.g00001.1bHLH family protein
FANhyb_rscf00000094.1.g00022.1bHLH family protein
FANhyb_rscf00000096.1.g00003.1bHLH family protein
FANhyb_rscf00000098.1.g00003.1bHLH family protein
FANhyb_rscf00000100.1.g00011.1bHLH family protein
FANhyb_rscf00000140.1.g00010.1bHLH family protein
FANhyb_rscf00000147.1.g00016.1bHLH family protein
FANhyb_rscf00000170.1.g00006.1bHLH family protein
FANhyb_rscf00000212.1.g00023.1bHLH family protein
FANhyb_rscf00000238.1.g00007.1bHLH family protein
FANhyb_rscf00000292.1.g00004.1bHLH family protein
FANhyb_rscf00000295.1.g00003.1bHLH family protein
FANhyb_rscf00000311.1.g00007.1bHLH family protein
FANhyb_rscf00000311.1.g00008.1bHLH family protein
FANhyb_rscf00000356.1.g00010.1bHLH family protein
FANhyb_rscf00000356.1.g00011.1bHLH family protein
FANhyb_rscf00000390.1.g00003.1bHLH family protein
FANhyb_rscf00000390.1.g00006.1bHLH family protein
FANhyb_rscf00000397.1.g00002.1bHLH family protein
FANhyb_rscf00000397.1.g00003.1bHLH family protein
FANhyb_rscf00000468.1.g00011.1bHLH family protein
FANhyb_rscf00000497.1.g00005.1bHLH family protein
FANhyb_rscf00000515.1.g00001.1bHLH family protein
FANhyb_rscf00000570.1.g00008.1bHLH family protein
FANhyb_rscf00000591.1.g00002.1bHLH family protein
FANhyb_rscf00000615.1.g00003.1bHLH family protein
FANhyb_rscf00000669.1.g00002.1bHLH family protein
FANhyb_rscf00000702.1.g00008.1bHLH family protein
FANhyb_rscf00000844.1.g00004.1bHLH family protein
FANhyb_rscf00000916.1.g00005.1bHLH family protein
FANhyb_rscf00000935.1.g00005.1bHLH family protein
FANhyb_rscf00000964.1.g00002.1bHLH family protein
FANhyb_rscf00001055.1.g00004.1bHLH family protein
FANhyb_rscf00001056.1.g00004.1bHLH family protein
FANhyb_rscf00001184.1.g00001.1bHLH family protein
FANhyb_rscf00001230.1.g00003.1bHLH family protein
FANhyb_rscf00001251.1.g00004.1bHLH family protein
FANhyb_rscf00001292.1.g00003.1bHLH family protein
FANhyb_rscf00001319.1.g00001.1bHLH family protein
FANhyb_rscf00001606.1.g00002.1bHLH family protein
FANhyb_rscf00001727.1.g00002.1bHLH family protein
FANhyb_rscf00002067.1.g00001.1bHLH family protein
FANhyb_rscf00002107.1.g00002.1bHLH family protein
FANhyb_rscf00002184.1.g00002.1bHLH family protein
FANhyb_rscf00002254.1.g00002.1bHLH family protein
FANhyb_rscf00002311.1.g00001.1bHLH family protein
FANhyb_rscf00002319.1.g00002.1bHLH family protein
FANhyb_rscf00002483.1.g00001.1bHLH family protein
FANhyb_rscf00002534.1.g00001.1bHLH family protein
FANhyb_rscf00002544.1.g00001.1bHLH family protein
FANhyb_rscf00002590.1.g00001.1bHLH family protein
FANhyb_rscf00002609.1.g00002.1bHLH family protein
FANhyb_rscf00002925.1.g00001.1bHLH family protein
FANhyb_rscf00003291.1.g00001.1bHLH family protein
FANhyb_rscf00003752.1.g00002.1bHLH family protein
FANhyb_rscf00003999.1.g00001.1bHLH family protein
FANhyb_rscf00004574.1.g00001.1bHLH family protein
FANhyb_rscf00004806.1.g00001.1bHLH family protein
FANhyb_rscf00005077.1.g00001.1bHLH family protein
FANhyb_rscf00005094.1.g00001.1bHLH family protein
FANhyb_rscf00005471.1.g00001.1bHLH family protein
FANhyb_rscf00005836.1.g00001.1bHLH family protein
FANhyb_rscf00006669.1.g00001.1bHLH family protein
FANhyb_rscf00006996.1.g00001.1bHLH family protein
FANhyb_rscf00007145.1.g00001.1bHLH 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