Functional characterization of natural variants found on the major stress inducible 70-kDa heat shock gene, HSPA1A, in humans.
Functional characterization of natural variants found on the major stress inducible 70-kDa heat shock gene, HSPA1A, in humans.
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DOI：
10.1016/j.bbrc.2018.10.148
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发表时间：
2018-12-02
影响因子：
3.1
通讯作者：
Nikolaidis N
中科院分区：
文献类型：
--
作者：
Oliverio R;Nguyen P;Kdeiss B;Ord S;Daniels AJ;Nikolaidis N
在这份报告中，我们研究了自然单核苷酸多态性对HSPA1A功能的影响，HSPA1A是人类主要的应激诱导型Hsp70基因。我们首先确定，所有突变蛋白质都保留了水解ATP的能力，但其中三种蛋白质的ATP水解速率显着低于野生型（WT）蛋白质。我们还使用等温滴定量热法，发现虽然所有突变体与蛋白质底物结合的解离常数与WT蛋白相似，但其中四个突变体的反应熵增加。我们还测试了这些突变是否影响HSPA1A重折叠热变性荧光素酶的能力。这些分析表明，一个突变导致显着降低水平，而第二个导致更高水平的重折叠酶。然后，我们确定突变是否影响HSPA1A阻止由携带亨廷顿蛋白的多聚谷氨酰胺引起的细胞凋亡的能力。该测定确定，与WT相比，突变中的三种引起细胞凋亡增加。我们的研究结果表明，虽然没有这些自然发生的突变存在的位置上的已知功能，一些改变的分子伴侣活动的HSPA1A最有可能通过影响其两个主要结构域之间的变构通信。
In this report, we investigated the effects of natural single nucleotide polymorphisms on the function of HSPA1A, the major stress-inducible Hsp70 gene in humans. We first established that all mutant proteins retain their ability to hydrolyze ATP, but three of them had a significantly lower rate of ATP hydrolysis as compared to the wild-type (WT) protein. We also used Isothermal Titration Calorimetry and found that although all mutants bind to protein substrate with dissociation constants similar to the WT protein, four of them had increased reaction entropies. We also tested whether these mutations affect the ability of HSPA1A to refold heat-denatured luciferase. These assays revealed that one mutation resulted in significantly lower levels while a second one resulted in higher levels of the refolded enzyme. We then determined whether the mutations affected the ability of HSPA1A to prevent apoptosis caused by poly-glutamine carrying huntingtin proteins. This assay determined that three of the mutations caused increased cell apoptosis as compared to the WT. Our results reveal that although none of these naturally occurring mutations exists on positions of known function, some alter the molecular chaperone activities of HSPA1A most probably by affecting the allosteric communication between its two major domains.
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影响因子：
2.9
作者：
O'Donnell JP;Marsh HM;Sondermann H;Sevier CS
通讯作者：
Sevier CS
影响因子：
4.6
作者：
Hess, Kyle;Oliverio, Ryan;Nikolaidis, Nikolas
通讯作者：
Nikolaidis, Nikolas
DOI：
10.1196/annals.1391.009
发表时间：
2007-01-01
期刊：
STRESS RESPONSES IN BIOLOGY AND MEDICINE
影响因子：
--
作者：
Macario, Alberto J. L.;De Macario, Everly Conway
通讯作者：
De Macario, Everly Conway
影响因子：
4.3
作者：
Chiappori, Federica;Merelli, Ivan;Morra, Giulia
通讯作者：
Morra, Giulia
影响因子：
4.8
作者：
OBrien, MC;Flaherty, KM;McKay, DB
通讯作者：
McKay, DB