PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Carica papaya
bHLH Family
Species TF ID Description
evm.model.supercontig_1024.1bHLH family protein
evm.model.supercontig_106.57bHLH family protein
evm.model.supercontig_115.71bHLH family protein
evm.model.supercontig_1.175bHLH family protein
evm.model.supercontig_1175.1bHLH family protein
evm.model.supercontig_117.94bHLH family protein
evm.model.supercontig_120.27bHLH family protein
evm.model.supercontig_12.1bHLH family protein
evm.model.supercontig_1213.3bHLH family protein
evm.model.supercontig_124.41bHLH family protein
evm.model.supercontig_129.19bHLH family protein
evm.model.supercontig_129.37bHLH family protein
evm.model.supercontig_131.7bHLH family protein
evm.model.supercontig_1383.2bHLH family protein
evm.model.supercontig_141.19bHLH family protein
evm.model.supercontig_14.15bHLH family protein
evm.model.supercontig_142.14bHLH family protein
evm.model.supercontig_157.5bHLH family protein
evm.model.supercontig_160.32bHLH family protein
evm.model.supercontig_17.155bHLH family protein
evm.model.supercontig_175.4bHLH family protein
evm.model.supercontig_177.1bHLH family protein
evm.model.supercontig_183.32bHLH family protein
evm.model.supercontig_1892.1bHLH family protein
evm.model.supercontig_19.156bHLH family protein
evm.model.supercontig_1938.2bHLH family protein
evm.model.supercontig_19.98bHLH family protein
evm.model.supercontig_200.36bHLH family protein
evm.model.supercontig_203.5bHLH family protein
evm.model.supercontig_20.63bHLH family protein
evm.model.supercontig_20.95bHLH family protein
evm.model.supercontig_21.176bHLH family protein
evm.model.supercontig_21.177bHLH family protein
evm.model.supercontig_212.3bHLH family protein
evm.model.supercontig_21.7bHLH family protein
evm.model.supercontig_23.65bHLH family protein
evm.model.supercontig_27.162bHLH family protein
evm.model.supercontig_27.35bHLH family protein
evm.model.supercontig_282.7bHLH family protein
evm.model.supercontig_289.6bHLH family protein
evm.model.supercontig_3.225bHLH family protein
evm.model.supercontig_3.503bHLH family protein
evm.model.supercontig_3.51bHLH family protein
evm.model.supercontig_36.191bHLH family protein
evm.model.supercontig_388.7bHLH family protein
evm.model.supercontig_4.112bHLH family protein
evm.model.supercontig_4.179bHLH family protein
evm.model.supercontig_4.181bHLH family protein
evm.model.supercontig_44.78bHLH family protein
evm.model.supercontig_48.15bHLH family protein
evm.model.supercontig_489.5bHLH family protein
evm.model.supercontig_489.6bHLH family protein
evm.model.supercontig_49.31bHLH family protein
evm.model.supercontig_50.37bHLH family protein
evm.model.supercontig_5.180bHLH family protein
evm.model.supercontig_52.26bHLH family protein
evm.model.supercontig_52.7bHLH family protein
evm.model.supercontig_52.97bHLH family protein
evm.model.supercontig_5.303bHLH family protein
evm.model.supercontig_53.118bHLH family protein
evm.model.supercontig_537.2bHLH family protein
evm.model.supercontig_55.142bHLH family protein
evm.model.supercontig_55.51bHLH family protein
evm.model.supercontig_55.64bHLH family protein
evm.model.supercontig_57.28bHLH family protein
evm.model.supercontig_57.85bHLH family protein
evm.model.supercontig_58.45bHLH family protein
evm.model.supercontig_59.132bHLH family protein
evm.model.supercontig_61.16bHLH family protein
evm.model.supercontig_6.130bHLH family protein
evm.model.supercontig_6.173bHLH family protein
evm.model.supercontig_62.160bHLH family protein
evm.model.supercontig_6.255bHLH family protein
evm.model.supercontig_65.44bHLH family protein
evm.model.supercontig_65.63bHLH family protein
evm.model.supercontig_69.31bHLH family protein
evm.model.supercontig_69.33bHLH family protein
evm.model.supercontig_69.52bHLH family protein
evm.model.supercontig_70.77bHLH family protein
evm.model.supercontig_71.72bHLH family protein
evm.model.supercontig_7.53bHLH family protein
evm.model.supercontig_8.103bHLH family protein
evm.model.supercontig_81.11bHLH family protein
evm.model.supercontig_8.199bHLH family protein
evm.model.supercontig_8.253bHLH family protein
evm.model.supercontig_82.59bHLH family protein
evm.model.supercontig_84.89bHLH family protein
evm.model.supercontig_85.115bHLH family protein
evm.model.supercontig_85.120bHLH family protein
evm.model.supercontig_92.83bHLH family protein
evm.model.supercontig_9.363bHLH family protein
evm.model.supercontig_97.78bHLH family protein
evm.model.supercontig_99.32bHLH family protein
evm.TU.contig_26556.1bHLH family protein
evm.TU.contig_27490.2bHLH family protein
evm.TU.contig_28125.2bHLH family protein
evm.TU.contig_30141.2bHLH family protein
evm.TU.contig_30708.1bHLH family protein
evm.TU.contig_31184.1bHLH family protein
evm.TU.contig_34101.1bHLH family protein
evm.TU.contig_36549.1bHLH family protein
evm.TU.contig_38183.1bHLH family protein
evm.TU.contig_45766.1bHLH family protein
evm.TU.contig_45808.1bHLH family protein
evm.TU.contig_46440.1bHLH 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