Plant Transcription Factor Database
Previous version: v3.0
Brassica napus
SBP Family
Species TF ID Description
GSBRNA2T00009986001SBP family protein
GSBRNA2T00010840001SBP family protein
GSBRNA2T00012443001SBP family protein
GSBRNA2T00018836001SBP family protein
GSBRNA2T00020688001SBP family protein
GSBRNA2T00024664001SBP family protein
GSBRNA2T00026248001SBP family protein
GSBRNA2T00030719001SBP family protein
GSBRNA2T00033324001SBP family protein
GSBRNA2T00034335001SBP family protein
GSBRNA2T00038356001SBP family protein
GSBRNA2T00038358001SBP family protein
GSBRNA2T00038835001SBP family protein
GSBRNA2T00043168001SBP family protein
GSBRNA2T00050076001SBP family protein
GSBRNA2T00051803001SBP family protein
GSBRNA2T00053169001SBP family protein
GSBRNA2T00055896001SBP family protein
GSBRNA2T00064576001SBP family protein
GSBRNA2T00064718001SBP family protein
GSBRNA2T00065108001SBP family protein
GSBRNA2T00066018001SBP family protein
GSBRNA2T00076919001SBP family protein
GSBRNA2T00078397001SBP family protein
GSBRNA2T00079960001SBP family protein
GSBRNA2T00082020001SBP family protein
GSBRNA2T00082768001SBP family protein
GSBRNA2T00083085001SBP family protein
GSBRNA2T00084688001SBP family protein
GSBRNA2T00084692001SBP family protein
GSBRNA2T00085301001SBP family protein
GSBRNA2T00085302001SBP family protein
GSBRNA2T00086890001SBP family protein
GSBRNA2T00087887001SBP family protein
GSBRNA2T00088261001SBP family protein
GSBRNA2T00089936001SBP family protein
GSBRNA2T00089937001SBP family protein
GSBRNA2T00095270001SBP family protein
GSBRNA2T00096385001SBP family protein
GSBRNA2T00096923001SBP family protein
GSBRNA2T00098900001SBP family protein
GSBRNA2T00101976001SBP family protein
GSBRNA2T00102380001SBP family protein
GSBRNA2T00104877001SBP family protein
GSBRNA2T00105779001SBP family protein
GSBRNA2T00106189001SBP family protein
GSBRNA2T00114722001SBP family protein
GSBRNA2T00117406001SBP family protein
GSBRNA2T00117407001SBP family protein
GSBRNA2T00119141001SBP family protein
GSBRNA2T00123166001SBP family protein
GSBRNA2T00132295001SBP family protein
GSBRNA2T00132740001SBP family protein
GSBRNA2T00132972001SBP family protein
GSBRNA2T00135341001SBP family protein
GSBRNA2T00142194001SBP family protein
GSBRNA2T00142279001SBP family protein
GSBRNA2T00142280001SBP family protein
GSBRNA2T00146589001SBP family protein
GSBRNA2T00147801001SBP family protein
GSBRNA2T00150582001SBP family protein
GSBRNA2T00152313001SBP family protein
GSBRNA2T00154374001SBP 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