PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Zostera marina
bHLH Family
Species TF ID Description
Zosma106g00660.1bHLH family protein
Zosma110g00150.1bHLH family protein
Zosma110g00340.1bHLH family protein
Zosma113g00480.1bHLH family protein
Zosma114g00360.1bHLH family protein
Zosma114g00860.1bHLH family protein
Zosma118g00550.1bHLH family protein
Zosma118g00580.1bHLH family protein
Zosma118g00600.1bHLH family protein
Zosma11g00130.1bHLH family protein
Zosma11g00170.1bHLH family protein
Zosma120g00020.1bHLH family protein
Zosma121g00370.1bHLH family protein
Zosma123g00440.1bHLH family protein
Zosma124g00100.1bHLH family protein
Zosma136g00350.1bHLH family protein
Zosma137g00180.1bHLH family protein
Zosma148g00260.1bHLH family protein
Zosma149g00100.1bHLH family protein
Zosma14g00200.1bHLH family protein
Zosma153g00280.1bHLH family protein
Zosma15g00570.1bHLH family protein
Zosma15g01220.1bHLH family protein
Zosma161g00440.1bHLH family protein
Zosma169g00450.1bHLH family protein
Zosma16g00330.1bHLH family protein
Zosma16g01620.1bHLH family protein
Zosma171g00310.1bHLH family protein
Zosma171g00350.1bHLH family protein
Zosma171g00490.1bHLH family protein
Zosma177g00200.1bHLH family protein
Zosma189g00360.1bHLH family protein
Zosma18g00430.1bHLH family protein
Zosma18g00700.1bHLH family protein
Zosma18g01140.1bHLH family protein
Zosma20g01260.1bHLH family protein
Zosma214g00240.1bHLH family protein
Zosma214g00260.1bHLH family protein
Zosma214g00460.1bHLH family protein
Zosma22g01000.1bHLH family protein
Zosma239g00140.1bHLH family protein
Zosma23g01210.1bHLH family protein
Zosma246g00260.1bHLH family protein
Zosma257g00080.1bHLH family protein
Zosma26g00560.1bHLH family protein
Zosma287g00240.1bHLH family protein
Zosma288g00210.1bHLH family protein
Zosma293g00070.1bHLH family protein
Zosma29g01200.1bHLH family protein
Zosma2g00480.1bHLH family protein
Zosma2g01070.1bHLH family protein
Zosma2g01630.1bHLH family protein
Zosma2g01700.1bHLH family protein
Zosma32g00920.1bHLH family protein
Zosma34g00070.1bHLH family protein
Zosma37g00430.1bHLH family protein
Zosma37g00460.1bHLH family protein
Zosma3g01560.1bHLH family protein
Zosma3g01570.1bHLH family protein
Zosma3g01590.1bHLH family protein
Zosma40g00280.1bHLH family protein
Zosma40g00370.1bHLH family protein
Zosma44g01030.1bHLH family protein
Zosma467g00090.1bHLH family protein
Zosma47g00090.1bHLH family protein
Zosma48g00330.1bHLH family protein
Zosma49g00850.1bHLH family protein
Zosma49g00920.1bHLH family protein
Zosma4g00200.1bHLH family protein
Zosma4g00580.1bHLH family protein
Zosma52g01380.1bHLH family protein
Zosma58g00740.1bHLH family protein
Zosma5g02450.1bHLH family protein
Zosma64g00560.1bHLH family protein
Zosma65g00950.1bHLH family protein
Zosma66g00730.1bHLH family protein
Zosma69g00060.1bHLH family protein
Zosma69g00790.1bHLH family protein
Zosma6g00780.1bHLH family protein
Zosma6g00860.1bHLH family protein
Zosma75g00410.1bHLH family protein
Zosma75g00600.1bHLH family protein
Zosma76g01020.1bHLH family protein
Zosma76g01060.1bHLH family protein
Zosma78g00380.1bHLH family protein
Zosma7g01270.1bHLH family protein
Zosma81g00950.1bHLH family protein
Zosma85g00170.1bHLH family protein
Zosma85g00210.1bHLH family protein
Zosma86g00080.1bHLH family protein
Zosma87g00390.1bHLH family protein
Zosma89g00630.1bHLH family protein
Zosma89g00880.1bHLH family protein
Zosma89g00960.1bHLH family protein
Zosma8g01330.1bHLH family protein
Zosma8g01800.1bHLH family protein
Zosma8g01850.1bHLH family protein
Zosma92g00180.1bHLH family protein
Zosma93g01000.1bHLH family protein
Zosma95g00360.1bHLH family protein
Zosma97g00930.1bHLH family protein
Zosma98g00100.1bHLH family protein
Zosma9g00010.1bHLH 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