水稻纤维素合酶催化亚基的编码基因BC88的表达分析

禾本科植物的脆秆突变体是进行次生细胞壁研究的理想材料。对水稻bc88突变体的前期研究表明,BC88编码一个纤维素合酶催化亚基OsCesA9。通过水稻遗传转化BC88启动子融合GUS的载体,检测到BC88在根、茎、叶、鞘、花中均有表达,并且在茎和根中表达量较高,这可能是由于BC88突变后影响了根系的正常发育及功能,进而影响地上部的生长,最终导致bc88半矮表型。将BC88与GFP的融合表达载体转入水稻和烟草表皮细胞中,共聚焦显微观察显示,OsCesA9定位在质膜上。质膜是纤维素合成的主要场所,这充分说明了OsCesA9是水稻次生细胞壁中纤维素合成必不可少的纤维素合酶催化亚基之一。本研究为BC88执行其生物学功能提供了新依据,对进一步认识该基因在调节次生细胞壁合成等方面的作用具有重要的意义。

Expression of OsBC88, a Rice Cellulose Synthase Catalytic Subunit Gene

Brittle culm mutant in gramineae plants is an ideal material for secondary cell wall research. Previous studies about bc88 mutant in rice show that BC88 encodes a cellulose synthase catalytic subunit, OsCesA9. The genetic transformation of rice by  BC88 promoter fused with GUS  vector   showed that  BC88 was expressed ubiquitously in root, stem, leaf, sheath, flower, with high expression in culm and root. The mutation in  BC88 may affect normal development and function of root, thereby affect the shoot growth and lead to semi dwarf phenotype. Transfer BC88 fused with GFP protein into rice and tobacco epidermal cells show that, OsCesA9  is located at plasma membrane where cellulose synthesized,   coinciding  with that  OsCesA9 is one of the essential functional CESA units for cellulose synthesis of secondary cell wall. These results provided new information for analysis of  BC88 biological function and it’s of great significance for the further understanding of  BC88 in regulating the secondary cell wall synthesis or other related process.