Specific heat shock proteins are transported into chloroplasts.
Specific heat shock proteins are transported into chloroplasts.
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特定的热休克蛋白被转运到叶绿体中。
DOI：
10.1073/pnas.83.2.361
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发表时间：
1986
影响因子：
11.1
通讯作者：
Joe L. Key
中科院分区：
文献类型：
--
作者：
Elizabeth Vierling;Michael L. Mishkind;Gregory W. Schmidt;Joe L. Key
我们证明，在三种植物-大豆，豌豆，玉米-某些核编码的热休克蛋白被运送到叶绿体。在体外翻译产物的多聚（A）-RNA从控制或热休克植物与分离的完整的豌豆叶绿体和进口蛋白质的差异进行了分析。在所有三个物种中，丰富的多肽21和27 kDa之间的存在于热休克样品和不存在的控制。这些多肽被保护免受胰蛋白酶和胰凝乳蛋白酶消化后，其输入到叶绿体和回收主要与可溶性叶绿体蛋白级分。从豌豆或玉米叶片中分离的叶绿体在热激温度下体内标记，但在正常生长温度下不标记，含有在体外观察到的相同多肽。放线菌酮可抑制热休克多肽的合成，但氯霉素不能抑制，进一步表明它们是细胞质蛋白质合成的产物。体外转运实验表明，叶绿体定位的热休克蛋白的合成是由热诱导的相应poly（A）-RNA的积累。非光合组织（白化的大豆下胚轴）在热激反应中也会产生相同的mRNA。
We demonstrate that in three plant species-soybean, pea, and corn-certain nuclear-encoded heat shock proteins are transported into chloroplasts. In vitro translation products of poly(A)-RNA from control or heat-shocked plants were incubated with isolated intact pea chloroplasts and differences in the profile of imported proteins were analyzed. In all three species, abundant polypeptides between 21 and 27 kDa are present in the heat shock sample and absent in the controls. These polypeptides are protected from trypsin and chymotrypsin digestion after their import into chloroplasts and are recovered primarily with the soluble chloroplast protein fraction. Chloroplasts isolated from pea or corn leaves labeled in vivo at heat shock temperatures, but not at normal growth temperatures, contain the same polypeptides observed in vitro. Synthesis of the heat shock polypeptides can be inhibited in vivo by cycloheximide but not by chloramphenicol, further indicating they are products of cytoplasmic protein synthesis. The in vitro transport experiments demonstrate that synthesis of the chloroplast-localized heat shock proteins results from heat-induced accumulation of the corresponding poly(A)-RNAs. The same mRNAs are also produced in response to heat shock by a nonphotosynthetic tissue, the etiolated soybean hypocotyl.