Forster S, Scarlett L, Lloyd J B
Department of Biological Sciences, University of Keele, U.K.
Biochim Biophys Acta. 1989 Sep 4;1013(1):7-10. doi: 10.1016/0167-4889(89)90120-1.
Cystinotic fibroblasts transferred from 37 degrees C to 28 degrees C accumulated additional cystine over the period from 4 to 7 days of incubation at 28 degrees C, after which the additional cystine was lost; warming (to 37 degrees C) of cells with elevated cystine stores led to rapid cystine loss. These results, taken together with previously published data showing cystine release from cystinotic fibroblasts incubated at above-normal temperature, are interpreted as indicating the presence in the cystinotic fibroblast lysosome membrane of a cystine-porter whose efficacy is increased by an increase in membrane fluidity. This porter may be the residual activity of the cystine porter that is known to be deficient in cystinosis, or it may be a second as yet unrecognized porter. It is further proposed that this porter is responsible for the presumed efflux of cystine from cystinotic lysosomes.
胱氨酸病成纤维细胞从37℃转移至28℃后，在28℃孵育4至7天的期间内积累了额外的胱氨酸，之后额外的胱氨酸丢失；将具有升高的胱氨酸储存量的细胞升温（至37℃）导致胱氨酸快速丢失。这些结果，与先前发表的显示胱氨酸病成纤维细胞在高于正常温度下孵育时胱氨酸释放的数据一起，被解释为表明在胱氨酸病成纤维细胞溶酶体膜中存在一种胱氨酸转运体，其功效因膜流动性增加而增强。这种转运体可能是已知在胱氨酸病中缺乏的胱氨酸转运体的残余活性，或者它可能是另一种尚未被识别的转运体。进一步提出，这种转运体负责胱氨酸病溶酶体中推测的胱氨酸外流。
