%0 Journal Article
%T Small and round seed 5 gene encodes alpha-tubulin regulating seed cell elongation in rice
%A Shuhei Segami
%A Izumi Kono
%A Tsuyu Ando
%A Masahiro Yano
%A Hidemi Kitano
%A Kotaro Miura
%A Yukimoto Iwasaki
%J Rice
%D 2012
%I BioMed Central
%R 10.1186/1939-8433-5-4
%X Seed size and weight are important traits for rice yield (Song and Ashikari 2008, Takeda and Matsuoka 2008). Several quantitative trait loci (QTLs) affecting seed size have been identified, namely GW2 encoding a RING-type protein that functions as an E3 ubiquitin ligase (Song et al. 2007), qSW5 encoding a novel protein with no known domains (Shoumura et al. 2008), and GS3 encoding a membrane protein with various conserved domains (Fan et al. 2006, Takano-Kai et al. 2009). Loss of GW2 and qSW5 function leads to a wider seed phenotype, and loss of GS3 function leads to a longer seed phenotype, both resulting in increased yield.Causal genes of the small (or short) seed mutants have also been identified, namely d1 (also named RGA1) encoding the heterotrimeric G protein alpha subunit (Ashikari et al. 1999, Fujisawa et al. 1999), d11 encoding a cytochrome P450 involved in brassinosteroid (BR) biosynthesis (Tanabe et al. 2005), d2 and brd2 encoding another type of cytochrome P450 involved in BR synthesis (Hong et al. 2003, Hong et al. 2005), d61 (also named OsBRI1) encoding the BR receptor (Yamamuro et al. 2000), srs1 encoding a novel protein that has no known functional domains (Abe et al. 2010), and finally, srs3 encoding a kinesin 13 protein (Kitagawa et al. 2010). During seed formation in rice, it was demonstrated that D1 regulates cell number (Izawa et al. 2010), and SRS1 and SRS3 regulate cell length (Abe et al. 2010, Kitagawa et al. 2010). From these observations, SRS1 and SRS3 seem to affect seed size through signaling pathways other than G-protein signal transduction.Although several genes regulating seed size have been identified, their molecular network underlying seed formation remains unclear. Here we report molecular cloning of a novel small and round seed mutant in Srs5 (Small and round seed 5). The results clearly demonstrated that Srs5 encodes alpha-tubulin and regulates cell elongation in rice seed.A mutant line, Kyudai No. 37, was identified by screening
%U http://www.thericejournal.com/content/5/1/4