我所水稻生物学国家重点实验室钱前博士课题组与中国科学院遗传与发育研究所李家洋院士课题组合作，成功克隆了具有DUF266结构域的高尔基体定位的II型膜蛋白BC10。BC10基因主要在水稻发育的厚壁组织和维管束细胞中表达，它的缺乏导致了纤维素和AGPs水平的下降，从而引起机械性能的削弱。研究成果发表在国际植物学权威杂志《The Plant Journal》上（电子版2008年10月11日刊出）。

BC10, A DUF266-Containing and Golgi-Located Type II Membrane Protein, Is Required for Cell Wall Biosynthesis in Rice (Oryza sativa L.)

Yihua Zhou,Shengben Li,Qian Qian,Dali Zeng,Mu Zhang,Longbiao Guo,Xiangling Liu,Baocai Zhang,Lingwei Deng,Xinfang Liu,Guanzheng Luo,Xiujie Wang and Jiayang Li.

The Plant Journal

DOI:10.1111/j.1365-313X.2008.03703.x

Abstract

Glycosyltransferases (GTs) are among the largest groups of enzymes required for the synthesis of complex wall polysaccharides and glycoproteins in plants. However, due to the limited number of related mutants that have observable phenotypes, the biological function(s) of most GTs in cell wall biosynthesis and assembly have remained elusive. We report here the isolation and an in-depth characterization of a brittle rice mutant, brittle culm 10 (bc10). The bc10 plants show pleiotropic phenotypes, including the brittleness of plant body and retarded developmental status. The BC10 gene was cloned through a map-based approach and encodes a Golgi-located type II membrane protein that contains a domain designated as Domain of Unknown Function 266 (DUF266) and represents a multiple gene family in rice. BC10 has low sequence similarity at the domain architecture to a Core2 β-1,6-N-acetylglucosaminyltransferase (C2GnT) and its in vitro enzymatic activity suggests that it functions as a glycosyltransferase. Monosaccharide analysis of total and fractioned wall residues revealed that bc10 had impaired cellulose biosynthesis. Immunolocalization and isolation of arabinogalactan-proteins (AGPs) between the wild type and bc10 showed that the level of AGPs in the mutant is significantly affected. BC10 is mainly expressed in the developing sclerenchyma and vascular bundle cells and its deficiency causes a reduction in the levels of cellulose and AGPs, leading to inferior mechanical properties.