PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Malus domestica
bHLH Family
Species TF ID Description
MDP0000029168bHLH family protein
MDP0000119495bHLH family protein
MDP0000121522bHLH family protein
MDP0000123893bHLH family protein
MDP0000123894bHLH family protein
MDP0000124019bHLH family protein
MDP0000124536bHLH family protein
MDP0000124672bHLH family protein
MDP0000125939bHLH family protein
MDP0000128058bHLH family protein
MDP0000129011bHLH family protein
MDP0000129787bHLH family protein
MDP0000131133bHLH family protein
MDP0000131874bHLH family protein
MDP0000133262bHLH family protein
MDP0000135282bHLH family protein
MDP0000136498bHLH family protein
MDP0000137325bHLH family protein
MDP0000138102bHLH family protein
MDP0000138721bHLH family protein
MDP0000139206bHLH family protein
MDP0000140864bHLH family protein
MDP0000142237bHLH family protein
MDP0000143208bHLH family protein
MDP0000145825bHLH family protein
MDP0000145937bHLH family protein
MDP0000147232bHLH family protein
MDP0000148221bHLH family protein
MDP0000149222bHLH family protein
MDP0000152070bHLH family protein
MDP0000153000bHLH family protein
MDP0000154272bHLH family protein
MDP0000155965bHLH family protein
MDP0000159013bHLH family protein
MDP0000159571bHLH family protein
MDP0000160256bHLH family protein
MDP0000160600bHLH family protein
MDP0000166245bHLH family protein
MDP0000167824bHLH family protein
MDP0000168695bHLH family protein
MDP0000168773bHLH family protein
MDP0000169102bHLH family protein
MDP0000170202bHLH family protein
MDP0000171866bHLH family protein
MDP0000173477bHLH family protein
MDP0000174149bHLH family protein
MDP0000175215bHLH family protein
MDP0000175282bHLH family protein
MDP0000176749bHLH family protein
MDP0000178319bHLH family protein
MDP0000178636bHLH family protein
MDP0000178778bHLH family protein
MDP0000178782bHLH family protein
MDP0000180376bHLH family protein
MDP0000182782bHLH family protein
MDP0000183700bHLH family protein
MDP0000183819bHLH family protein
MDP0000183948bHLH family protein
MDP0000191607bHLH family protein
MDP0000195072bHLH family protein
MDP0000195579bHLH family protein
MDP0000195608bHLH family protein
MDP0000198037bHLH family protein
MDP0000198333bHLH family protein
MDP0000198404bHLH family protein
MDP0000198858bHLH family protein
MDP0000200355bHLH family protein
MDP0000204989bHLH family protein
MDP0000205030bHLH family protein
MDP0000205113bHLH family protein
MDP0000205358bHLH family protein
MDP0000205807bHLH family protein
MDP0000209483bHLH family protein
MDP0000210155bHLH family protein
MDP0000210715bHLH family protein
MDP0000210979bHLH family protein
MDP0000213494bHLH family protein
MDP0000213892bHLH family protein
MDP0000214472bHLH family protein
MDP0000215269bHLH family protein
MDP0000215587bHLH family protein
MDP0000216053bHLH family protein
MDP0000218785bHLH family protein
MDP0000219146bHLH family protein
MDP0000220675bHLH family protein
MDP0000224302bHLH family protein
MDP0000225159bHLH family protein
MDP0000225299bHLH family protein
MDP0000225680bHLH family protein
MDP0000226497bHLH family protein
MDP0000228273bHLH family protein
MDP0000229007bHLH family protein
MDP0000229725bHLH family protein
MDP0000231650bHLH family protein
MDP0000242554bHLH family protein
MDP0000242865bHLH family protein
MDP0000243628bHLH family protein
MDP0000245233bHLH family protein
MDP0000245538bHLH family protein
MDP0000246258bHLH family protein
MDP0000247912bHLH family protein
MDP0000248312bHLH family protein
MDP0000249060bHLH family protein
MDP0000249405bHLH family protein
MDP0000249969bHLH family protein
MDP0000252899bHLH family protein
MDP0000253576bHLH family protein
MDP0000254650bHLH family protein
MDP0000256276bHLH family protein
MDP0000256492bHLH family protein
MDP0000259495bHLH family protein
MDP0000261293bHLH family protein
MDP0000262020bHLH family protein
MDP0000263981bHLH family protein
MDP0000264179bHLH family protein
MDP0000264803bHLH family protein
MDP0000264827bHLH family protein
MDP0000267178bHLH family protein
MDP0000269890bHLH family protein
MDP0000271420bHLH family protein
MDP0000273365bHLH family protein
MDP0000273574bHLH family protein
MDP0000274003bHLH family protein
MDP0000275635bHLH family protein
MDP0000275840bHLH family protein
MDP0000275844bHLH family protein
MDP0000279087bHLH family protein
MDP0000280921bHLH family protein
MDP0000281167bHLH family protein
MDP0000281613bHLH family protein
MDP0000281689bHLH family protein
MDP0000282600bHLH family protein
MDP0000283606bHLH family protein
MDP0000285780bHLH family protein
MDP0000286589bHLH family protein
MDP0000287358bHLH family protein
MDP0000288670bHLH family protein
MDP0000289642bHLH family protein
MDP0000290263bHLH family protein
MDP0000290934bHLH family protein
MDP0000291132bHLH family protein
MDP0000291499bHLH family protein
MDP0000293310bHLH family protein
MDP0000295440bHLH family protein
MDP0000295593bHLH family protein
MDP0000296508bHLH family protein
MDP0000296814bHLH family protein
MDP0000298705bHLH family protein
MDP0000299846bHLH family protein
MDP0000301871bHLH family protein
MDP0000301999bHLH family protein
MDP0000304669bHLH family protein
MDP0000305976bHLH family protein
MDP0000307685bHLH family protein
MDP0000309179bHLH family protein
MDP0000312274bHLH family protein
MDP0000313643bHLH family protein
MDP0000314321bHLH family protein
MDP0000315500bHLH family protein
MDP0000318216bHLH family protein
MDP0000318229bHLH family protein
MDP0000318772bHLH family protein
MDP0000318951bHLH family protein
MDP0000319248bHLH family protein
MDP0000319726bHLH family protein
MDP0000320691bHLH family protein
MDP0000320739bHLH family protein
MDP0000321049bHLH family protein
MDP0000323291bHLH family protein
MDP0000386580bHLH family protein
MDP0000391743bHLH family protein
MDP0000401086bHLH family protein
MDP0000405748bHLH family protein
MDP0000406270bHLH family protein
MDP0000410728bHLH family protein
MDP0000420192bHLH family protein
MDP0000421809bHLH family protein
MDP0000423329bHLH family protein
MDP0000435722bHLH family protein
MDP0000436338bHLH family protein
MDP0000439540bHLH family protein
MDP0000442310bHLH family protein
MDP0000461727bHLH family protein
MDP0000484847bHLH family protein
MDP0000491271bHLH family protein
MDP0000494181bHLH family protein
MDP0000502440bHLH family protein
MDP0000514358bHLH family protein
MDP0000523715bHLH family protein
MDP0000523812bHLH family protein
MDP0000525527bHLH family protein
MDP0000534784bHLH family protein
MDP0000545428bHLH family protein
MDP0000560255bHLH family protein
MDP0000562627bHLH family protein
MDP0000565402bHLH family protein
MDP0000573178bHLH family protein
MDP0000581816bHLH family protein
MDP0000603546bHLH family protein
MDP0000603926bHLH family protein
MDP0000606021bHLH family protein
MDP0000617077bHLH family protein
MDP0000617871bHLH family protein
MDP0000625989bHLH family protein
MDP0000628479bHLH family protein
MDP0000641681bHLH family protein
MDP0000644807bHLH family protein
MDP0000646823bHLH family protein
MDP0000652631bHLH family protein
MDP0000662999bHLH family protein
MDP0000672131bHLH family protein
MDP0000672760bHLH family protein
MDP0000687064bHLH family protein
MDP0000687814bHLH family protein
MDP0000704958bHLH family protein
MDP0000710285bHLH family protein
MDP0000711374bHLH family protein
MDP0000711774bHLH family protein
MDP0000713910bHLH family protein
MDP0000714374bHLH family protein
MDP0000725991bHLH family protein
MDP0000729514bHLH family protein
MDP0000731330bHLH family protein
MDP0000738505bHLH family protein
MDP0000753946bHLH family protein
MDP0000779358bHLH family protein
MDP0000782908bHLH family protein
MDP0000788304bHLH family protein
MDP0000790939bHLH family protein
MDP0000791364bHLH family protein
MDP0000794858bHLH family protein
MDP0000794913bHLH family protein
MDP0000799392bHLH family protein
MDP0000817710bHLH family protein
MDP0000821314bHLH family protein
MDP0000825749bHLH family protein
MDP0000829998bHLH family protein
MDP0000837139bHLH family protein
MDP0000859492bHLH family protein
MDP0000866611bHLH family protein
MDP0000876738bHLH family protein
MDP0000879337bHLH family protein
MDP0000884108bHLH family protein
MDP0000900024bHLH family protein
MDP0000902699bHLH family protein
MDP0000907218bHLH family protein
MDP0000934866bHLH family protein
MDP0000944210bHLH family protein
MDP0000945492bHLH family protein
MDP0000946515bHLH 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