PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Thellungiella parvula
bHLH Family
Species TF ID Description
Tp1g01020bHLH family protein
Tp1g01430bHLH family protein
Tp1g02030bHLH family protein
Tp1g04530bHLH family protein
Tp1g04610bHLH family protein
Tp1g04980bHLH family protein
Tp1g08130bHLH family protein
Tp1g08750bHLH family protein
Tp1g09050bHLH family protein
Tp1g09250bHLH family protein
Tp1g09290bHLH family protein
Tp1g11120bHLH family protein
Tp1g11440bHLH family protein
Tp1g16350bHLH family protein
Tp1g19970bHLH family protein
Tp1g21830bHLH family protein
Tp1g22410bHLH family protein
Tp1g22900bHLH family protein
Tp1g23870bHLH family protein
Tp1g23970bHLH family protein
Tp1g25810bHLH family protein
Tp1g26570bHLH family protein
Tp1g26900bHLH family protein
Tp1g28280bHLH family protein
Tp1g30180bHLH family protein
Tp1g36660bHLH family protein
Tp1g37790bHLH family protein
Tp1g37890bHLH family protein
Tp2g01010bHLH family protein
Tp2g01630bHLH family protein
Tp2g02900bHLH family protein
Tp2g04920bHLH family protein
Tp2g07960bHLH family protein
Tp2g11500bHLH family protein
Tp2g11570bHLH family protein
Tp2g11630bHLH family protein
Tp2g14970bHLH family protein
Tp2g15870bHLH family protein
Tp2g17480bHLH family protein
Tp2g18920bHLH family protein
Tp2g24120bHLH family protein
Tp2g24500bHLH family protein
Tp2g25790bHLH family protein
Tp2g27400bHLH family protein
Tp2g28160bHLH family protein
Tp2g28430bHLH family protein
Tp2g28730bHLH family protein
Tp2g29570bHLH family protein
Tp2g29620bHLH family protein
Tp3g05070bHLH family protein
Tp3g06280bHLH family protein
Tp3g17550bHLH family protein
Tp3g17880bHLH family protein
Tp3g18680bHLH family protein
Tp3g19390bHLH family protein
Tp3g19920bHLH family protein
Tp3g20860bHLH family protein
Tp3g21400bHLH family protein
Tp3g21660bHLH family protein
Tp3g21790bHLH family protein
Tp3g21800bHLH family protein
Tp3g27680bHLH family protein
Tp3g27940bHLH family protein
Tp3g29570bHLH family protein
Tp3g30190bHLH family protein
Tp3g31710bHLH family protein
Tp3g33420bHLH family protein
Tp4g01740bHLH family protein
Tp4g01750bHLH family protein
Tp4g01760bHLH family protein
Tp4g03250bHLH family protein
Tp4g10970bHLH family protein
Tp4g13700bHLH family protein
Tp4g13710bHLH family protein
Tp4g14190bHLH family protein
Tp4g17100bHLH family protein
Tp4g20590bHLH family protein
Tp4g22550bHLH family protein
Tp4g23440bHLH family protein
Tp4g23560bHLH family protein
Tp4g24450bHLH family protein
Tp4g24470bHLH family protein
Tp4g25140bHLH family protein
Tp4g25270bHLH family protein
Tp4g28550bHLH family protein
Tp4g28840bHLH family protein
Tp4g28970bHLH family protein
Tp5g01280bHLH family protein
Tp5g01400bHLH family protein
Tp5g03920bHLH family protein
Tp5g04890bHLH family protein
Tp5g05600bHLH family protein
Tp5g05610bHLH family protein
Tp5g05800bHLH family protein
Tp5g11860bHLH family protein
Tp5g14210bHLH family protein
Tp5g14280bHLH family protein
Tp5g21530bHLH family protein
Tp5g23280bHLH family protein
Tp5g23300bHLH family protein
Tp5g23920bHLH family protein
Tp5g24060bHLH family protein
Tp5g24120bHLH family protein
Tp5g26360bHLH family protein
Tp5g27300bHLH family protein
Tp5g29030bHLH family protein
Tp5g29680bHLH family protein
Tp6g00110bHLH family protein
Tp6g00190bHLH family protein
Tp6g00520bHLH family protein
Tp6g02500bHLH family protein
Tp6g03820bHLH family protein
Tp6g07700bHLH family protein
Tp6g13050bHLH family protein
Tp6g13070bHLH family protein
Tp6g14000bHLH family protein
Tp6g14030bHLH family protein
Tp6g15390bHLH family protein
Tp6g16640bHLH family protein
Tp6g18670bHLH family protein
Tp6g18880bHLH family protein
Tp6g19690bHLH family protein
Tp6g28910bHLH family protein
Tp6g32860bHLH family protein
Tp6g33650bHLH family protein
Tp6g34830bHLH family protein
Tp6g38600bHLH family protein
Tp6g40630bHLH family protein
Tp7g00630bHLH family protein
Tp7g02200bHLH family protein
Tp7g03050bHLH family protein
Tp7g12010bHLH family protein
Tp7g12480bHLH family protein
Tp7g14960bHLH family protein
Tp7g16240bHLH family protein
Tp7g19420bHLH family protein
Tp7g23420bHLH family protein
Tp7g23430bHLH family protein
Tp7g26810bHLH family protein
Tp7g27030bHLH family protein
Tp7g27740bHLH family protein
Tp7g28850bHLH family protein
Tp7g31600bHLH family protein
Tp7g32320bHLH family protein
Tp7g33840bHLH family protein
Tp7g34190bHLH family protein
Tp7g35490bHLH family protein
Tp_un0002_054bHLH family protein
Tp_un0010_011bHLH family protein
Tp_un0036_004bHLH family protein
Tp_un0398_001bHLH family protein
Tp_un0429_001bHLH family protein
Tp_un0744_001bHLH family protein
Tp_un1580_001bHLH 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