PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Ipomoea trifida
bHLH Family
Species TF ID Description
Itr_sc000002.1_g00047.1bHLH family protein
Itr_sc000002.1_g00050.1bHLH family protein
Itr_sc000003.1_g00017.1bHLH family protein
Itr_sc000009.1_g00019.1bHLH family protein
Itr_sc000010.1_g00057.1bHLH family protein
Itr_sc000011.1_g00140.1bHLH family protein
Itr_sc000021.1_g00041.1bHLH family protein
Itr_sc000022.1_g00030.1bHLH family protein
Itr_sc000027.1_g00005.1bHLH family protein
Itr_sc000031.1_g00007.1bHLH family protein
Itr_sc000031.1_g00012.1bHLH family protein
Itr_sc000032.1_g00021.1bHLH family protein
Itr_sc000036.1_g00031.1bHLH family protein
Itr_sc000037.1_g00007.1bHLH family protein
Itr_sc000038.1_g00006.1bHLH family protein
Itr_sc000042.1_g00004.1bHLH family protein
Itr_sc000049.1_g00015.1bHLH family protein
Itr_sc000049.1_g00016.1bHLH family protein
Itr_sc000049.1_g00017.1bHLH family protein
Itr_sc000051.1_g00004.1bHLH family protein
Itr_sc000051.1_g00014.1bHLH family protein
Itr_sc000056.1_g00007.1bHLH family protein
Itr_sc000061.1_g00025.1bHLH family protein
Itr_sc000063.1_g00003.1bHLH family protein
Itr_sc000065.1_g00034.1bHLH family protein
Itr_sc000073.1_g00007.1bHLH family protein
Itr_sc000079.1_g00045.1bHLH family protein
Itr_sc000083.1_g00016.1bHLH family protein
Itr_sc000083.1_g00061.1bHLH family protein
Itr_sc000090.1_g00019.1bHLH family protein
Itr_sc000098.1_g00038.1bHLH family protein
Itr_sc000102.1_g00010.1bHLH family protein
Itr_sc000115.1_g00002.1bHLH family protein
Itr_sc000115.1_g00045.1bHLH family protein
Itr_sc000115.1_g00046.1bHLH family protein
Itr_sc000116.1_g00003.1bHLH family protein
Itr_sc000120.1_g00018.1bHLH family protein
Itr_sc000136.1_g00008.1bHLH family protein
Itr_sc000142.1_g00018.1bHLH family protein
Itr_sc000144.1_g00004.1bHLH family protein
Itr_sc000154.1_g00015.1bHLH family protein
Itr_sc000178.1_g00028.1bHLH family protein
Itr_sc000179.1_g00022.1bHLH family protein
Itr_sc000185.1_g00001.1bHLH family protein
Itr_sc000187.1_g00018.1bHLH family protein
Itr_sc000190.1_g00016.1bHLH family protein
Itr_sc000203.1_g00032.1bHLH family protein
Itr_sc000213.1_g00001.1bHLH family protein
Itr_sc000215.1_g00022.1bHLH family protein
Itr_sc000216.1_g00026.1bHLH family protein
Itr_sc000228.1_g00019.1bHLH family protein
Itr_sc000234.1_g00006.1bHLH family protein
Itr_sc000257.1_g00031.1bHLH family protein
Itr_sc000270.1_g00013.1bHLH family protein
Itr_sc000276.1_g00003.1bHLH family protein
Itr_sc000289.1_g00007.1bHLH family protein
Itr_sc000292.1_g00005.1bHLH family protein
Itr_sc000299.1_g00022.1bHLH family protein
Itr_sc000315.1_g00004.1bHLH family protein
Itr_sc000341.1_g00006.1bHLH family protein
Itr_sc000345.1_g00010.1bHLH family protein
Itr_sc000365.1_g00002.1bHLH family protein
Itr_sc000373.1_g00013.1bHLH family protein
Itr_sc000394.1_g00004.1bHLH family protein
Itr_sc000401.1_g00016.1bHLH family protein
Itr_sc000412.1_g00011.1bHLH family protein
Itr_sc000415.1_g00019.1bHLH family protein
Itr_sc000418.1_g00013.1bHLH family protein
Itr_sc000439.1_g00012.1bHLH family protein
Itr_sc000454.1_g00006.1bHLH family protein
Itr_sc000487.1_g00026.1bHLH family protein
Itr_sc000497.1_g00006.1bHLH family protein
Itr_sc000539.1_g00008.1bHLH family protein
Itr_sc000544.1_g00011.1bHLH family protein
Itr_sc000552.1_g00004.1bHLH family protein
Itr_sc000552.1_g00020.1bHLH family protein
Itr_sc000553.1_g00011.1bHLH family protein
Itr_sc000555.1_g00001.1bHLH family protein
Itr_sc000555.1_g00004.1bHLH family protein
Itr_sc000583.1_g00008.1bHLH family protein
Itr_sc000587.1_g00015.1bHLH family protein
Itr_sc000604.1_g00017.1bHLH family protein
Itr_sc000605.1_g00007.1bHLH family protein
Itr_sc000605.1_g00008.1bHLH family protein
Itr_sc000640.1_g00015.1bHLH family protein
Itr_sc000667.1_g00004.1bHLH family protein
Itr_sc000682.1_g00004.1bHLH family protein
Itr_sc000684.1_g00003.1bHLH family protein
Itr_sc000685.1_g00007.1bHLH family protein
Itr_sc000695.1_g00005.1bHLH family protein
Itr_sc000712.1_g00015.1bHLH family protein
Itr_sc000740.1_g00003.1bHLH family protein
Itr_sc000748.1_g00009.1bHLH family protein
Itr_sc000749.1_g00014.1bHLH family protein
Itr_sc000767.1_g00001.1bHLH family protein
Itr_sc000819.1_g00008.1bHLH family protein
Itr_sc000844.1_g00018.1bHLH family protein
Itr_sc000881.1_g00001.1bHLH family protein
Itr_sc000886.1_g00006.1bHLH family protein
Itr_sc000942.1_g00007.1bHLH family protein
Itr_sc000988.1_g00002.1bHLH family protein
Itr_sc001037.1_g00004.1bHLH family protein
Itr_sc001092.1_g00010.1bHLH family protein
Itr_sc001167.1_g00009.1bHLH family protein
Itr_sc001191.1_g00003.1bHLH family protein
Itr_sc001232.1_g00009.1bHLH family protein
Itr_sc001235.1_g00001.1bHLH family protein
Itr_sc001239.1_g00007.1bHLH family protein
Itr_sc001239.1_g00009.1bHLH family protein
Itr_sc001239.1_g00015.1bHLH family protein
Itr_sc001240.1_g00007.1bHLH family protein
Itr_sc001265.1_g00006.1bHLH family protein
Itr_sc001312.1_g00003.1bHLH family protein
Itr_sc001441.1_g00002.1bHLH family protein
Itr_sc001441.1_g00003.1bHLH family protein
Itr_sc001441.1_g00004.1bHLH family protein
Itr_sc001441.1_g00005.1bHLH family protein
Itr_sc001447.1_g00001.1bHLH family protein
Itr_sc001448.1_g00001.1bHLH family protein
Itr_sc001448.1_g00002.1bHLH family protein
Itr_sc001448.1_g00004.1bHLH family protein
Itr_sc001448.1_g00005.1bHLH family protein
Itr_sc001474.1_g00001.1bHLH family protein
Itr_sc001474.1_g00002.1bHLH family protein
Itr_sc001474.1_g00003.1bHLH family protein
Itr_sc001502.1_g00002.1bHLH family protein
Itr_sc001552.1_g00002.1bHLH family protein
Itr_sc001576.1_g00004.1bHLH family protein
Itr_sc001694.1_g00004.1bHLH family protein
Itr_sc001721.1_g00007.1bHLH family protein
Itr_sc001728.1_g00004.1bHLH family protein
Itr_sc001761.1_g00002.1bHLH family protein
Itr_sc001761.1_g00006.1bHLH family protein
Itr_sc001826.1_g00002.1bHLH family protein
Itr_sc001868.1_g00009.1bHLH family protein
Itr_sc001877.1_g00011.1bHLH family protein
Itr_sc001935.1_g00001.1bHLH family protein
Itr_sc002061.1_g00007.1bHLH family protein
Itr_sc002092.1_g00013.1bHLH family protein
Itr_sc002201.1_g00002.1bHLH family protein
Itr_sc002318.1_g00004.1bHLH family protein
Itr_sc002379.1_g00008.1bHLH family protein
Itr_sc002389.1_g00003.1bHLH family protein
Itr_sc002583.1_g00009.1bHLH family protein
Itr_sc002586.1_g00001.1bHLH family protein
Itr_sc002759.1_g00001.1bHLH family protein
Itr_sc002759.1_g00002.1bHLH family protein
Itr_sc002759.1_g00003.1bHLH family protein
Itr_sc002759.1_g00004.1bHLH family protein
Itr_sc002759.1_g00005.1bHLH family protein
Itr_sc002822.1_g00002.1bHLH family protein
Itr_sc002834.1_g00001.1bHLH family protein
Itr_sc002864.1_g00001.1bHLH family protein
Itr_sc002913.1_g00002.1bHLH family protein
Itr_sc003071.1_g00001.1bHLH family protein
Itr_sc003191.1_g00002.1bHLH family protein
Itr_sc003191.1_g00003.1bHLH family protein
Itr_sc003230.1_g00004.1bHLH family protein
Itr_sc003239.1_g00003.1bHLH family protein
Itr_sc003308.1_g00001.1bHLH family protein
Itr_sc003477.1_g00001.1bHLH family protein
Itr_sc003485.1_g00001.1bHLH family protein
Itr_sc003487.1_g00001.1bHLH family protein
Itr_sc003726.1_g00001.1bHLH family protein
Itr_sc003765.1_g00001.1bHLH family protein
Itr_sc003973.1_g00002.1bHLH family protein
Itr_sc003991.1_g00001.1bHLH family protein
Itr_sc004102.1_g00001.1bHLH family protein
Itr_sc010164.1_g00001.1bHLH family protein
Itr_sc010930.1_g00001.1bHLH family protein
Itr_sc047470.1_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