The chloroplast small heat-shock protein oligomer is not phosphorylated and does not dissociate during heat stress in vivo.
The chloroplast small heat-shock protein oligomer is not phosphorylated and does not dissociate during heat stress in vivo.
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叶绿体小热激蛋白寡聚体在体内热应激期间不被磷酸化并且不解离。
DOI：
10.1104/pp.116.3.1151
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发表时间：
1998
期刊：
影响因子：
7.4
通讯作者：
Vierling,E
中科院分区：
文献类型：
--
作者：
Suzuki,TC;Krawitz,DC;Vierling,E
植物在热胁迫下合成几种小的（15- 30kd单体）热休克蛋白（sHSPs），包括核编码的叶绿体定位的sHSP （HSP21）。细胞质内sHSPs以大的寡聚物形式存在（约200-800 kD），主要或完全由sHSPs组成。哺乳动物sHSP的磷酸化引起寡聚体解离，这似乎对sHSP功能的调节很重要。我们研究了叶绿体HSP21的天然结构和磷酸化，以了解该蛋白的基本特性，并将其与细胞质sHSPs进行比较。天然HSP21复合物的表观大小为100 ~ 200 kD，在热应激过程中不解离。我们没有发现HSP21或植物细胞质sHSPs在体内被磷酸化的证据。从热应激豌豆（Pisum sativumL.）叶片中纯化的部分HSP21复合体不含除HSP21以外的蛋白质。在大肠杆菌中表达成熟的重组豌豆和拟南芥HSP21，并将纯化的重组拟南芥HSP21组装成与热胁迫叶片组织中观察到的HSP21复合物具有相同表观分子质量的同源寡聚物。我们认为，叶绿体HSP21的天然功能形式是一个含有9个或更多HSP21亚基的大型寡聚复合物，并且植物sHSPs不受磷酸化诱导解离的调节。
Plants synthesize several classes of small (15- to 30-kD monomer) heat-shock proteins (sHSPs) in response to heat stress, including a nuclear-encoded, chloroplast-localized sHSP (HSP21). Cytosolic sHSPs exist as large oligomers (approximately 200–800 kD) composed solely or primarily of sHSPs. Phosphorylation of mammalian sHSPs causes oligomer dissociation, which appears to be important for regulation of sHSP function. We examined the native structure and phosphorylation of chloroplast HSP21 to understand this protein's basic properties and to compare it with cytosolic sHSPs. The apparent size of native HSP21 complexes was > 200 kD and they did not dissociate during heat stress. We found no evidence that HSP21 or the plant cytosolic sHSPs are phosphorylated in vivo. A partial HSP21 complex purified from heat-stressed pea (Pisum sativumL.) leaves contained no proteins other than HSP21. Mature recombinant pea andArabidopsis thalianaHSP21 were expressed inEscherichia coli, and purified recombinant Arabidopsis HSP21 assembled into homo-oligomeric complexes with the same apparent molecular mass as HSP21 complexes observed in heat-stressed leaf tissue. We propose that the native, functional form of chloroplast HSP21 is a large, oligomeric complex containing nine or more HSP21 subunits, and that plant sHSPs are not regulated by phosphorylation-induced dissociation.
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定位于叶绿体的热休克蛋白是热休克蛋白真核超家族的成员。
影响因子：
11.4
作者：
E. Vierling;R. T. Nagao;A. DeRocher;Lisa M. Harris
通讯作者：
Lisa M. Harris
DOI：
10.1016/s0021-9258(19)61958-7
发表时间：
1994-11
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
K. Osteryoung;E. Vierling
通讯作者：
K. Osteryoung;E. Vierling
特定的热休克蛋白被转运到叶绿体中。
DOI：
10.1073/pnas.83.2.361
发表时间：
1986
影响因子：
11.1
作者：
Elizabeth Vierling;Michael L. Mishkind;Gregory W. Schmidt;Joe L. Key
通讯作者：
Joe L. Key
C4单子叶植物幼叶叶绿体热激蛋白的表征
影响因子：
6.4
作者：
A. Clarke;C. Critchley
通讯作者：
C. Critchley
大麦叶叶绿体中热休克蛋白复合物的鉴定。
影响因子：
7.4
作者：
A. Clarke;Christa Critchley
通讯作者：
Christa Critchley