Murray D L, Kohorn B D
Botany Department, Duke University, Durham, NC 27706.
Plant Mol Biol. 1991 Jan;16(1):71-9. doi: 10.1007/BF00017918.
We are interested in the mechanism of insertion of proteins into the chloroplast thylakoid membrane and the role that accessory pigments may play in this process. For this reason we have begun a molecular analysis of mutant plants deficient in pigments that associate with thylakoid membrane proteins. We have characterized plants that are homozygous for the previously isolated, recessive mutation chlorina-1 (ch-1) of Arabidopsis thaliana. Despite the lack of chlorophyll b and light-harvesting proteins of photosystem II (LHCPII) near normal levels of LHCPII mRNA are found in the mutant, in contrast to LHCPII mRNA levels in carotenoid-deficient mutants. The LHCPII mRNA of chlorina-1 plants can be translated in vitro so it is likely that LHCPII is not stable in ch-1 plants. Moreover, the thylakoid membranes of ch-1 plants remain appressed even though LHCPII levels are drastically reduced.
我们对蛋白质插入叶绿体类囊体膜的机制以及辅助色素在这一过程中可能发挥的作用感兴趣。因此，我们已开始对与类囊体膜蛋白相关的色素缺乏的突变植物进行分子分析。我们对拟南芥先前分离出的隐性突变chlorina-1（ch-1）的纯合植物进行了表征。尽管缺乏叶绿素b和光系统II的捕光蛋白（LHCPII），但在突变体中发现LHCPII mRNA水平接近正常水平，这与类胡萝卜素缺乏的突变体中的LHCPII mRNA水平形成对比。chlorina-1植物的LHCPII mRNA可以在体外翻译，所以LHCPII在ch-1植物中可能不稳定。此外，即使LHCPII水平大幅降低，ch-1植物的类囊体膜仍保持紧贴状态。
