Department of Botany, University of Edinburgh, Edinburgh, Scotland, United Kingdom.
Plant Physiol. 1981 Jun;67(6):1090-6. doi: 10.1104/pp.67.6.1090.
Cell-free protein synthesizing systems have been used to study the developmental changes in the synthesis of chloroplast proteins in the cotyledons of cucumber seedlings grown in the light or in the dark. Escherichia coli and wheat germ in vitro protein synthesizing systems have been used to assay the changes in the levels of the mRNA's coding for ribulose 1,5-bisphosphate carboxylase (RuBPCase). The large subunit of cucumber RuBPCase has been identified among the translation products of the E. coli system. The wheat germ system translates the cucumber mRNA coding for the small subunit of RuBPCase to produce a 25,000 molecular weight precursor polypeptide. Plastids isolated from light-grown cotyledons were used to study developmental changes in their capacity to synthesize protein. The data obtained indicate that in the light there is an initial 48-hour period of accumulation of the mRNA's coding for the large and small subunits of RuBPCase, coupled with an increase in the capacity of the isolated plastids to synthesize protein. This is followed by a decline. This decline is not reflected in the accumulation of RuBPCase in the cotyledons which remains constant over the period of study.
无细胞蛋白质合成系统已被用于研究在光或暗中生长的黄瓜幼苗子叶中叶绿体蛋白质合成的发育变化。大肠杆菌和小麦胚体外蛋白质合成系统已被用于测定编码核酮糖 1,5-二磷酸羧化酶（RuBPCase）的 mRNA 水平的变化。黄瓜 RuBPCase 的大亚基已被鉴定为大肠杆菌系统翻译产物之一。小麦胚系统翻译黄瓜 mRNA 编码 RuBPCase 的小亚基，产生一个 25,000 分子量的前体多肽。从光生长的子叶中分离出的质体用于研究其合成蛋白质的能力的发育变化。获得的数据表明，在光下，存在 RuBPCase 的大亚基和小亚基的 mRNA 的初始 48 小时积累期，同时伴随着分离质体合成蛋白质能力的增加。随后是下降。这种下降没有反映在子叶中 RuBPCase 的积累上，在研究期间 RuBPCase 的积累保持不变。
