HeLa细胞核和核骨架含有肌动蛋白

提取HeLa细胞核并制备核骨架标本，以抗肌动蛋白抗体为探针，采用SDS－PAGE、免疫荧光和免疫印迹等方法，对HeLa细胞细胞核和核骨架中的肌动蛋白进行了研究，并用鬼笔环肽荧光染色方法研究了其中的F－肌动蛋白。在荧光显微镜下观察到：代表肌动蛋白的特异性荧光分布在细胞核和核骨架中，说明肌支蛋白是细胞核和核骨架的固有成分；代表F－肌动蛋白的特异性荧光存在于细胞和核骨架中，说明细胞核和核骨架含有F－肌动蛋白。免疫印迹结果进一步肯定了细胞核和核骨架中肌动蛋白的存在。

Actin is Located in theNucleus and Nuclear Matrix of HeLa Cells

HeLa cell nuclei were isolated and the nuclear matrix specimenswere prepared. After labelled with an anti-actin antibody and FITC-conjugated secondary antibody, both the nuclei and nuclear matrix specimens were observed to emanate specific yellow-green fluorescence. The fluorescent signals in the nuclear matrix were much stronger than that in the nuclei, and the signals in former were widespread throughout the whole structure while that in the latter were mainly defined to their peripheral regions. A 43kD band was revealed in nuclei and nuclear matrix specimens by SDS-PAGE, and was then proved to be actin by Western blot, confirming the immuno-fluorescence observations. When stained with TRICT-conjugated phalloidin, both the nuclei and nuclear matrix specimens were found to give off specific, red fluorescent signals which represent the location of F-actin (filamentous actin), and the pattern of TRITC signals distribution in the nuclei and nuclear matrix showed similarity with that of FITC signals. The existence and significance of actin and F-actinin the nuclei and nuclear matrix were discussed.