PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Pyrus bretschneideri
bHLH Family
Species TF ID Description
Pbr000207.1bHLH family protein
Pbr000225.1bHLH family protein
Pbr000228.1bHLH family protein
Pbr000478.1bHLH family protein
Pbr000622.1bHLH family protein
Pbr000853.1bHLH family protein
Pbr001568.2bHLH family protein
Pbr001646.1bHLH family protein
Pbr001754.1bHLH family protein
Pbr002358.2bHLH family protein
Pbr002444.1bHLH family protein
Pbr003532.1bHLH family protein
Pbr003533.1bHLH family protein
Pbr004256.2bHLH family protein
Pbr004361.1bHLH family protein
Pbr004454.1bHLH family protein
Pbr004663.1bHLH family protein
Pbr004750.1bHLH family protein
Pbr004866.1bHLH family protein
Pbr004947.1bHLH family protein
Pbr005087.1bHLH family protein
Pbr005095.1bHLH family protein
Pbr005918.1bHLH family protein
Pbr005984.1bHLH family protein
Pbr006313.1bHLH family protein
Pbr006319.1bHLH family protein
Pbr006544.1bHLH family protein
Pbr006687.1bHLH family protein
Pbr007168.1bHLH family protein
Pbr007246.1bHLH family protein
Pbr007344.1bHLH family protein
Pbr007757.1bHLH family protein
Pbr007793.1bHLH family protein
Pbr008209.1bHLH family protein
Pbr008210.1bHLH family protein
Pbr008711.1bHLH family protein
Pbr008831.1bHLH family protein
Pbr009042.1bHLH family protein
Pbr009044.1bHLH family protein
Pbr009072.1bHLH family protein
Pbr009179.1bHLH family protein
Pbr009541.1bHLH family protein
Pbr009756.1bHLH family protein
Pbr010125.1bHLH family protein
Pbr010573.1bHLH family protein
Pbr010581.1bHLH family protein
Pbr010800.1bHLH family protein
Pbr010922.1bHLH family protein
Pbr011113.1bHLH family protein
Pbr011456.1bHLH family protein
Pbr011460.1bHLH family protein
Pbr011463.1bHLH family protein
Pbr011525.1bHLH family protein
Pbr011696.1bHLH family protein
Pbr012051.1bHLH family protein
Pbr013186.1bHLH family protein
Pbr013200.1bHLH family protein
Pbr013246.1bHLH family protein
Pbr013314.2bHLH family protein
Pbr013349.1bHLH family protein
Pbr013624.1bHLH family protein
Pbr013706.1bHLH family protein
Pbr013792.1bHLH family protein
Pbr013869.1bHLH family protein
Pbr013890.1bHLH family protein
Pbr014375.1bHLH family protein
Pbr014934.1bHLH family protein
Pbr015480.2bHLH family protein
Pbr015624.1bHLH family protein
Pbr016145.1bHLH family protein
Pbr016539.1bHLH family protein
Pbr016589.1bHLH family protein
Pbr016684.1bHLH family protein
Pbr016686.1bHLH family protein
Pbr016723.1bHLH family protein
Pbr016725.1bHLH family protein
Pbr017127.1bHLH family protein
Pbr017379.1bHLH family protein
Pbr018354.1bHLH family protein
Pbr018411.1bHLH family protein
Pbr018724.1bHLH family protein
Pbr019435.1bHLH family protein
Pbr019649.1bHLH family protein
Pbr019660.1bHLH family protein
Pbr019661.2bHLH family protein
Pbr019740.1bHLH family protein
Pbr019789.1bHLH family protein
Pbr020204.1bHLH family protein
Pbr020294.1bHLH family protein
Pbr021160.1bHLH family protein
Pbr021351.1bHLH family protein
Pbr021888.1bHLH family protein
Pbr021976.1bHLH family protein
Pbr022391.1bHLH family protein
Pbr022398.1bHLH family protein
Pbr022522.1bHLH family protein
Pbr022523.1bHLH family protein
Pbr023051.1bHLH family protein
Pbr023206.1bHLH family protein
Pbr023339.1bHLH family protein
Pbr023429.1bHLH family protein
Pbr023800.1bHLH family protein
Pbr024260.1bHLH family protein
Pbr024262.1bHLH family protein
Pbr024263.1bHLH family protein
Pbr024517.1bHLH family protein
Pbr024631.1bHLH family protein
Pbr025153.1bHLH family protein
Pbr025166.1bHLH family protein
Pbr025285.1bHLH family protein
Pbr025316.1bHLH family protein
Pbr025320.2bHLH family protein
Pbr026078.1bHLH family protein
Pbr026439.1bHLH family protein
Pbr026441.1bHLH family protein
Pbr026442.1bHLH family protein
Pbr026823.1bHLH family protein
Pbr026824.1bHLH family protein
Pbr027099.1bHLH family protein
Pbr027108.1bHLH family protein
Pbr027332.1bHLH family protein
Pbr027356.1bHLH family protein
Pbr027397.1bHLH family protein
Pbr027398.1bHLH family protein
Pbr027399.1bHLH family protein
Pbr027424.1bHLH family protein
Pbr027487.1bHLH family protein
Pbr027564.1bHLH family protein
Pbr028196.1bHLH family protein
Pbr028256.1bHLH family protein
Pbr028681.2bHLH family protein
Pbr028813.1bHLH family protein
Pbr029607.1bHLH family protein
Pbr030017.2bHLH family protein
Pbr030032.1bHLH family protein
Pbr030115.1bHLH family protein
Pbr030521.1bHLH family protein
Pbr030523.1bHLH family protein
Pbr030944.1bHLH family protein
Pbr031107.2bHLH family protein
Pbr031549.1bHLH family protein
Pbr032336.1bHLH family protein
Pbr032736.1bHLH family protein
Pbr032962.1bHLH family protein
Pbr034181.1bHLH family protein
Pbr034262.2bHLH family protein
Pbr034713.1bHLH family protein
Pbr034838.2bHLH family protein
Pbr035149.1bHLH family protein
Pbr035437.1bHLH family protein
Pbr035703.1bHLH family protein
Pbr035981.1bHLH family protein
Pbr037054.1bHLH family protein
Pbr037113.1bHLH family protein
Pbr037115.1bHLH family protein
Pbr037384.1bHLH family protein
Pbr037501.1bHLH family protein
Pbr037618.1bHLH family protein
Pbr037679.1bHLH family protein
Pbr037716.1bHLH family protein
Pbr038026.1bHLH family protein
Pbr038274.1bHLH family protein
Pbr038570.1bHLH family protein
Pbr038573.1bHLH family protein
Pbr038574.1bHLH family protein
Pbr038717.1bHLH family protein
Pbr038723.1bHLH family protein
Pbr038923.1bHLH family protein
Pbr039112.1bHLH family protein
Pbr039170.1bHLH family protein
Pbr039557.1bHLH family protein
Pbr039686.1bHLH family protein
Pbr040195.1bHLH family protein
Pbr040318.1bHLH family protein
Pbr040436.1bHLH family protein
Pbr040660.1bHLH family protein
Pbr040691.1bHLH family protein
Pbr040759.1bHLH family protein
Pbr040761.1bHLH family protein
Pbr040909.1bHLH family protein
Pbr040914.1bHLH family protein
Pbr040944.1bHLH family protein
Pbr041115.1bHLH family protein
Pbr041171.1bHLH family protein
Pbr041211.1bHLH family protein
Pbr041312.1bHLH family protein
Pbr041336.1bHLH family protein
Pbr041410.1bHLH family protein
Pbr041470.1bHLH family protein
Pbr041632.1bHLH family protein
Pbr041633.1bHLH family protein
Pbr041849.1bHLH family protein
Pbr041944.1bHLH family protein
Pbr042040.1bHLH family protein
Pbr042466.1bHLH family protein
Pbr042554.1bHLH family protein
Pbr042561.1bHLH 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