Takahashi N, De Luca L M, Breitman T R
Department of Health Chemistry, Hoshi University, Tokyo, Japan.
Biochem Biophys Res Commun. 1997 Oct 9;239(1):80-4. doi: 10.1006/bbrc.1997.7434.
Retinoylation (retinoic acid acylation) is a post-translation modification of proteins occurring in a variety of mammalian cell lines and in vivo. To gain further knowledge of the role of retinoylation we studied it in NIH 3T3 cells and NIH 3T3 cells transformed by an activated Ha-ras oncogene (NIH Ha-ras-3T3 cells). In serum-free medium retinoic acid (RA) inhibited growth of NIH 3T3 cells but did not inhibit growth of NIH Ha-ras-3T3 cells. After incubation with [3H]RA, the level of retinoylated protein in NIH 3T3 cells was about 1.5-fold greater than in NIH Ha-ras-3T3 cells. On one-dimensional polyacrylamide gel electrophoresis, both the rate and the extent of retinoylation were greater in NIH 3T3 cells. We detected about 40 retinoylated proteins in NIH 3T3 cells by two-dimensional polyacrylamide gel electrophoresis. Only about 15 proteins were retinoylated, but at reduced levels, in NIH Ha-ras-3T3 cells. These results suggest that the activated ras oncogene inhibits retinoylation. This inhibition may in turn be related to the loss of other RA responses of NIH 3T3 cells, including growth inhibition, retinoic acid catabolism, down-regulation of fibronectin biosynthesis, and induction of tissue-type transglutaminase, which are not seen to the same extent in NIH Ha-ras-3T3 cells.
视黄酰化（视黄酸酰化）是一种发生在多种哺乳动物细胞系和体内的蛋白质翻译后修饰。为了进一步了解视黄酰化的作用，我们在NIH 3T3细胞和由活化的Ha-ras癌基因转化的NIH 3T3细胞（NIH Ha-ras-3T3细胞）中对其进行了研究。在无血清培养基中，视黄酸（RA）抑制NIH 3T3细胞的生长，但不抑制NIH Ha-ras-3T3细胞的生长。用[3H]RA孵育后，NIH 3T3细胞中视黄酰化蛋白的水平比NIH Ha-ras-3T3细胞高约1.5倍。在一维聚丙烯酰胺凝胶电泳中，NIH 3T3细胞中视黄酰化的速率和程度都更高。通过二维聚丙烯酰胺凝胶电泳，我们在NIH 3T3细胞中检测到约40种视黄酰化蛋白。在NIH Ha-ras-3T3细胞中，只有约15种蛋白被视黄酰化，但水平降低。这些结果表明，活化的ras癌基因抑制视黄酰化。这种抑制反过来可能与NIH 3T3细胞其他视黄酸反应的丧失有关，包括生长抑制、视黄酸分解代谢、纤连蛋白生物合成的下调以及组织型转谷氨酰胺酶的诱导，而在NIH Ha-ras-3T3细胞中这些反应的程度不同。
