Ran Q, Wadhwa R, Kawai R, Kaul S C, Sifers R N, Bick R J, Smith J R, Pereira-Smith O M
Roy M. and Phyllis Gough Huffington Center on Aging, Department of Pathology, Baylor College of Medicine, One Baylor Plaza, Houston, Texas, 77030, USA.
Biochem Biophys Res Commun. 2000 Aug 18;275(1):174-9. doi: 10.1006/bbrc.2000.3237.
Subcellular fractionation and immunofluorescence microscopy were used to identify the specific sites of intracellular residence of mortalin, also called a mitochondrial homologue of the hsp70 family, in immortal human cell lines previously assigned to four distinct complementation groups (A-D) for indefinite cell division. In addition to the mitochondria it was seen in the endoplasmic reticulum (ER) fractions of all the cell lines analyzed. Interestingly, three of the group A cells lines (EJ, GM639, and HT1080), in addition to the mitochondria and ER, exhibited cytosolically (extra-organelle) localized pool of mortalin. These findings demonstrate that mortalin is not present exclusively in mitochondria. Its residence in different organelles may be the basis of differential distribution observed previously in different human cell lines.
亚细胞分级分离和免疫荧光显微镜技术被用于鉴定mortalin（也称为hsp70家族的线粒体同源物）在永生人类细胞系中的细胞内特定驻留位点，这些细胞系先前被归为四个不同的互补组（A - D）以进行无限期细胞分裂。除了线粒体之外，在所分析的所有细胞系的内质网（ER）组分中也能看到它。有趣的是，A组的三个细胞系（EJ、GM639和HT1080），除了线粒体和内质网之外，还表现出mortalin定位于胞质溶胶（细胞器外）的池。这些发现表明，mortalin并非仅存在于线粒体中。它在不同细胞器中的驻留可能是先前在不同人类细胞系中观察到的差异分布的基础。
