PlantRegMap/PlantTFDB v5.0
Plant Transcription Factor Database
Previous version: v3.0 v4.0
Ipomoea nil
SBP Family
Species TF ID Description
XP_019155751.1SBP family protein
XP_019155752.1SBP family protein
XP_019155753.1SBP family protein
XP_019155754.1SBP family protein
XP_019155755.1SBP family protein
XP_019156944.1SBP family protein
XP_019159042.1SBP family protein
XP_019159548.1SBP family protein
XP_019159549.1SBP family protein
XP_019163336.1SBP family protein
XP_019165047.1SBP family protein
XP_019166257.1SBP family protein
XP_019166258.1SBP family protein
XP_019167069.1SBP family protein
XP_019167070.1SBP family protein
XP_019170060.1SBP family protein
XP_019170520.1SBP family protein
XP_019170521.1SBP family protein
XP_019170523.1SBP family protein
XP_019170524.1SBP family protein
XP_019171998.1SBP family protein
XP_019172005.1SBP family protein
XP_019180488.1SBP family protein
XP_019180489.1SBP family protein
XP_019180610.1SBP family protein
XP_019180611.1SBP family protein
XP_019180612.1SBP family protein
XP_019180910.1SBP family protein
XP_019180911.1SBP family protein
XP_019180927.1SBP family protein
XP_019180928.1SBP family protein
XP_019186327.1SBP family protein
XP_019187445.1SBP family protein
XP_019187446.1SBP family protein
XP_019188927.1SBP family protein
XP_019193671.1SBP family protein
XP_019193939.1SBP family protein
XP_019199796.1SBP family protein
XP_019199798.1SBP family protein
XP_019199799.1SBP family protein
XP_019199818.1SBP family protein
XP_019199819.1SBP family protein
XP_019199820.1SBP family protein
XP_019199876.1SBP family protein
XP_019199877.1SBP family protein
SBP Family Introduction

SQUAMOSA promoter binding proteins (SBPs) form a major family of plant-specific transcription factors related to flower development. Although SBPs are heterogeneous in primary structure, they share a highly conserved DNA-binding domain (DBD) that has been suggested to be zinc binding. Here we report the NMR solution structures of DBDs of two SBPs of Arabidopsis thaliana, SPL4 and SPL7. The two share essentially the same structural features. Each structure contains two zinc-binding sites consisting of eight Cys or His residues in a Cys3HisCys2HisCys or Cys6HisCys sequence motif in which the first four residues coordinate to one zinc and the last four coordinate to the other. These structures are dissimilar to other known zinc-binding structures, and thus represent a novel type of zinc-binding motif. The electrostatic profile on the surface suggested that a continuous region, including all the conserved basic residues, is involved in the DNA binding, the mode of which is likely to be novel as well.

Yamasaki K, Kigawa T, Inoue M, Tateno M, Yamasaki T, Yabuki T, Aoki M, Seki E, Matsuda T, Nunokawa E, Ishizuka Y, Terada T, Shirouzu M, Osanai T, Tanaka A, Seki M, Shinozaki K, Yokoyama S.
A novel zinc-binding motif revealed by solution structures of DNA-binding domains of Arabidopsis SBP-family transcription factors
J Mol Biol. 2004 Mar 12;337(1):49-63.
PMID: 15001351

SBP-box genes were first characterized as SQUAMOSA promoter binding proteins (SBPs) to regulate the expression of MADS-box genes in early flower development of A. majus (Klein et al., 1996). Since then, SBP-box genes have been identified in many plants including green alga, moss, silver birch, A. majus, Arabidopsis and maize. They play critical roles in regulating flower and fruit development as well as other physiological processes ([Moreno et al., 1997],[Eriksson et al., 2004], [Lannenpaa et al., 2004], [Arazi et al., 2005] and [Kropat et al., 2005]). It has been reported that Arabidopsis SPL3, SPL8 and SPL14 involves in flowering, sporogenesis, GA signaling and toxin resistance ([Cardon et al., 1997], [Unte et al., 2003], [Stone et al., 2005] and [Zhang et al., 2006]) while maize tga1 and tomato LeSPL-CNR affect fruit development ([Wang et al., 2005a] and [Manning et al., 2006]).

SBP-box genes encode proteins sharing a conserved DNA-binding domain of 79 amino acid residues. It has been proved that the DNA-binding domain of SBP-box genes is necessary and sufficient to bind to a palindromic GTAC core motif ([Klein et al., 1996], [Cardon et al., 1997], [Cardon et al., 1999], [Lannenpaa et al., 2004] and [Birkenbihl et al., 2005]). Studies on the NMR solution structure of the fragment of Arabidopsis SPL4 and SPL7 revealed that the DNA-binding domain of SBPs consisted of two separate zinc-binding sites. One zinc finger is C3H or C4 and the other is C2HC (Yamasaki et al., 2004 K. Yamasaki et al.,).

Guo AY, Zhu QH, Gu X, Ge S, Yang J, Luo J.
Genome-wide identification and evolutionary analysis of the plant specific SBP-box transcription factor family.
Gene. 2008 Jul 15;418(1-2):1-8.
PMID: 18495384