BiP/Kar2p serves as a molecular chaperone during carboxypeptidase Y folding in yeast.
BiP/Kar2p serves as a molecular chaperone during carboxypeptidase Y folding in yeast.
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BIP/KAR2P在酵母中羧肽酶y折叠期间用作分子伴侣。
DOI：
10.1083/jcb.130.1.41
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发表时间：
1995-07
影响因子：
7.8
通讯作者：
HELENIUS, A
中科院分区：
文献类型：
--
作者：
SIMONS, JF;FERRONOVICK, S;ROSE, MD;HELENIUS, A
虽然BiP与许多新合成的蛋白质短暂地联系在一起，但并没有被证明是与内质网中新合成的蛋白质的折叠和寡聚直接相关的必要成分。为了确定它是否需要作为分子伴侣，我们分析了几株Bip基因温度敏感突变的酵母菌株内源酵母糖蛋白羧基肽酶Y(CPY)的成熟度。这些Kar2突变株以前已经被发现在不允许的温度下存在易位缺陷(Vogel，J.P.，L.M.Misra和M.D.Rose，1990)。J.Cell Biol，110：1885-1895)。为了绕过易位障碍，我们在允许的温度下使用DTT来延迟折叠和细胞内转运。然后，我们跟踪内质网保留的CPY在转移到不允许的温度和DTT稀释后的成熟情况。在没有功能性伴侣的情况下，cpy聚集，不能被氧化，留在内质网中。在野生型细胞中，Bip结合是暂时的，标记的cpy在任何时候都不超过10%-15%，而在突变菌株中，30%-100%的cpy仍然与Bip结合。在杂合的二倍体品系中，cpy成熟并正常退出内质网。综上所述，这些结果为Bip作为分子伴侣在cpy折叠中发挥关键作用提供了明确的证据。
Although transiently associated with numerous newly synthesized proteins, BiP has not been shown to be an essential component directly linked to the folding and oligomerization of newly synthesized proteins in the endoplasmic reticulum. To determine whether it is needed as a molecular chaperone, we analyzed the maturation of an endogenous yeast glycoprotein, carboxypeptidase Y (CPY) in several yeast strains with temperature-sensitive mutations in BiP. These kar2 mutant strains have previously been found to be defective in translocation at the nonpermissive temperature (Vogel, J. P., L. M. Misra, and M. D. Rose, 1990. J. Cell Biol, 110:1885-1895). To circumvent the translocation block, we used DTT at permissive temperature to delay folding and intracellular transport. We then followed the maturation of the ER- retained CPY after shifting to the nonpermissive temperature and dilution of the DTT. Without the functional chaperone, CPY aggregated, failed to be oxidized, and remained in the ER. In contrast to wild-type cells, in which BiP binding was transient with no more than 10-15% of labeled CPY associated at any time, 30-100% of the CPY remained associated with BiP in the mutant strains. In a heterozygous diploid strain, CPY matured and exited the ER normally. Taken together, the results provide clear evidence that BiP plays a critical role as a molecular chaperone in CPY folding.
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影响因子：
11.4
作者：
BRAAKMAN, I;HELENIUS, J;HELENIUS, A
通讯作者：
HELENIUS, A
影响因子：
2.9
作者：
ENDRIZZI, JA;BREDDAM, K;REMINGTON, SJ
通讯作者：
REMINGTON, SJ
影响因子：
7.8
作者：
DOMS, RW;KELLER, DS;BALCH, WE
通讯作者：
BALCH, WE
影响因子：
11.4
作者：
DORNER, AJ;WASLEY, LC;KAUFMAN, RJ
通讯作者：
KAUFMAN, RJ
影响因子：
56.9
作者：
HAMMOND, C;HELENIUS, A
通讯作者：
HELENIUS, A