THE CYCLOPHILIN HOMOLOG NINAA IS REQUIRED IN THE SECRETORY PATHWAY
THE CYCLOPHILIN HOMOLOG NINAA IS REQUIRED IN THE SECRETORY PATHWAY
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DOI：
10.1016/0092-8674(91)90177-z
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发表时间：
1991-10-18
期刊：
影响因子：
64.5
通讯作者：
ZUKER, CS
中科院分区：
文献类型：
--
作者：
COLLEY, NJ;BAKER, EK;ZUKER, CS
在果蝇中，主要的视紫红质Rh 1在R1-R6感光细胞的内质网（ER）结合的核糖体中合成，然后被转运到横纹肌，在那里它在光转导中起作用。亲环素同系物ninaA的突变导致Rh 1视蛋白减少90%。亲环素已被证明是肽基-脯氨酰顺反异构酶，并参与催化蛋白质折叠。我们现在发现ninaA基因的突变严重抑制了视蛋白从内质网的转运，导致了内质网池在感光细胞中的大量积累。这些结果表明ninaA在ER中起作用。有趣的是，ninaA和Rh 1也共定位于分泌囊泡，这表明Rh 1可能需要ninaA，因为它通过分泌途径的远端隔室。这些结果进行了讨论，亲环蛋白在蛋白质折叠和细胞内蛋白质运输的可能作用。
In Drosophila, the major rhodopsin Rh1 is synthesized in endoplasmic reticulum (ER)-bound ribosomes of the R1-R6 photoreceptor cells and is then transported to the rhabdomeres where it functions in phototransduction. Mutations in the cyclophilin homolog ninaA lead to a 90% reduction in Rh1 opsin. Cyclophilins have been shown to be peptidyl-prolyl cis-trans isomerases and have been implicated in catalyzing protein folding. We now show that mutations in the ninaA gene severely inhibit opsin transport from the ER, leading to dramatic accumulations of ER cisternae in the photoreceptor cells. These results demonstrate that ninaA functions in the ER. Interestingly, ninaA and Rh1 also colocalize to secretory vesicles, suggesting that Rh1 may require ninaA as it travels through the distal compartments of the secretory pathway. These results are discussed in relation to the possible role of cyclophilins in protein folding and intracellular protein trafficking.