CAJ | 학술논문

叶绿体在植物碳水化合物代谢中起着至关重要的作用,然而有关碳水化合物代谢在叶绿体发育过程中的功能却知之甚少。从水稻中克隆了一个 Oryza sativa Branching Enzyme 1(OsBE1)基因,该基因编码一个糖苷水解酶13家族的蛋白。OsBE1与拟南芥 AtBE1的一致性为66%,但与水稻典型淀粉分支酶的一致性仅约为40%。该基因的T-DNA 插入功能缺失突变体 osbe1幼苗白化,且其白化表型不能用外源糖类拯救。osbe1突变体幼苗最终在三叶期死亡。淀粉染色表明, osbe1突变体中淀粉的含量与野生型无明显差异。进一步的研究表明, osbe1突变体叶绿体数目较少,且无明显的基质片层结构。构建了 OsBE1基因过量表达载体 pCAMBIA1300-35S-OsBE1,并将其转化水稻中花11。获得的108株转基因水稻中,77株表现不同程度的黄化。本文初步揭示了碳水化合物代谢调控叶绿体发育的机制,并为深入研究糖苷水解酶 BE1的功能奠定了基础。
협록체재식물탄수화합물대사중기착지관중요적작용,연이유관탄수화합물대사재협록체발육과정중적공능각지지심소。종수도중극륭료일개 Oryza sativa Branching Enzyme 1(OsBE1)기인,해기인편마일개당감수해매13가족적단백。OsBE1여의남개 AtBE1적일치성위66%,단여수도전형정분분지매적일치성부약위40%。해기인적T-DNA 삽입공능결실돌변체 osbe1유묘백화,차기백화표형불능용외원당류증구。osbe1돌변체유묘최종재삼협기사망。정분염색표명, osbe1돌변체중정분적함량여야생형무명현차이。진일보적연구표명, osbe1돌변체협록체수목교소,차무명현적기질편층결구。구건료 OsBE1기인과량표체재체 pCAMBIA1300-35S-OsBE1,병장기전화수도중화11。획득적108주전기인수도중,77주표현불동정도적황화。본문초보게시료탄수화합물대사조공협록체발육적궤제,병위심입연구당감수해매 BE1적공능전정료기출。
Chloroplast plays an important role in plant carbohydrate metabolism; however the function of carbohydrate metabo-lism in the chloroplast development is poorly understood. The Oryza sativa Branching Enzyme 1 (OsBE1) gene, encoding a gly-coside hydrolase family 13 protein, was cloned from rice. The identity between OsBE1 and Arabidopsis AtBE1 is 66%, but only 40% between OsBE1 and the classical starch branching enzymes in rice. A T-DNA insertion mutant of OsBE1 gene was identified. The seedlings of the osbe1 mutant were albino, and died at the three-leaf stage. This albino phenotype could not be rescued by exogenous carbohydrate. Starch staining showed no obvious difference in starch content between osbe1 and the wild type. Further studies showed that there were less chloroplasts in osbe1 mutant than in wild type, and there was no obvious stroma lamella in the osbe1 chloroplast. The overexpression vector pCAMBIA1300-35S-OsBE1 was constructed and transformed into rice variety Zhonghua 11. Finally, 108 transgenic lines were obtained and 77 lines of them showed etiolation in different degrees. The work not only sheds a novel insight into the regulation mechanism of carbohydrate metabolism on chloroplast development, but also lays a foundation for further understanding of the OsBE1’s function.