Transforming ras proteins accelerate hormone-induced maturation and stimulate cyclic AMP phosphodiesterase in Xenopus oocytes.
Transforming ras proteins accelerate hormone-induced maturation and stimulate cyclic AMP phosphodiesterase in Xenopus oocytes.
复制标题
转化 ras 蛋白可加速激素诱导的成熟并刺激爪蟾卵母细胞中的环 AMP 磷酸二酯酶。
DOI：
10.1128/mcb.10.4.1689-1696.1990
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发表时间：
1990
影响因子：
5.3
通讯作者：
Gibbs,JB
中科院分区：
文献类型：
--
作者：
Sadler,SE;Maller,JL;Gibbs,JB
转化 Harvey (Ha)rasoncogene 产品加速了由胰岛素、胰岛素样生长因子 1 或黄体酮诱导的爪蟾细胞成熟的时间进程。转化构建体[Val-12]Ha p21 和[Val-12，Thr-59]Ha p21 在加速生长肽诱导的反应方面表现出相同的效力和功效。正常 Ha p21 的效力仅为 12 位含有缬氨酸的突变体的 60% 和五分之一。相反，两个非转化构建体，[Val-12，Ala-35，Leu-36，Thr-59]Ha p21 和 [Val-12，Thr-59]Ha(term-174) p21，对激素诱导的成熟的时间进程没有影响。转化草蛋白对激素诱导的成熟的影响与其刺激体内磷酸二酯酶活性的能力相关，在显微注射200μM环[ 3 H]AMP后测量。当胰岛素治疗 90 分钟后注射 p21 时，与激素治疗或单独注射 p21 后测量的结果相比，磷酸二酯酶活性没有增加，但在胰岛素治疗的前 90 分钟内观察到 p21 和胰岛素对酶活性的累加效应。尽管在体内测定开始时与底物共注射时，正常Ha p21和转化的[Val-12，Thr-59]Ha p21将卵母细胞磷酸二酯酶刺激至相同水平，但转化蛋白引起了更持续的酶活性刺激。这些结果表明，与胰岛素诱导的成熟相关的环AMP磷酸二酯酶活性的刺激涉及非洲爪蟾细胞中rasoncogene产物的生长促进作用。
Transforming Harvey (Ha)rasoncogene products accelerated the time course ofXenopusoocyte maturation induced by insulin, insulinlike growth factor 1, or progesterone. The transforming constructs, [Val-12]Ha p21 and [Val-12, Thr-59]Ha p21, displayed equal potency and efficacy in their abilities to accelerate the growth peptide-induced response. Normal Ha p21 was only 60% as powerful and one-fifth as potent as the mutants containing valine in the 12 position. In contrast, two nontransforming constructs, [Val-12, Ala-35, Leu-36, Thr-59]Ha p21 and [Val-12, Thr-59]Ha(term-174) p21, had no effect on the time course of hormone-induced maturation. Effects of the transformingrasproteins on hormone-induced maturation correlated with their abilities to stimulate in vivo phosphodiesterase activity measured after microinjection of 200 μΜ cyclic [3H] AMP. When p21 injection followed 90 min of insulin treatment, there was no increase in phosphodiesterase activity over that measured after hormone treatment or p21 injection alone, but additive effects of p21 and insulin on enzyme activity were observed during the first 90 min of insulin treatment. Even though normal Ha p21 and transforming [Val-12, Thr-59]Ha p21 stimulated oocyte phosphodiesterase to equal levels when coinjected with substrate at the initiation of the in vivo assay, the transforming protein elicited a more sustained stimulation of enzyme activity. These results suggest that stimulation of a cyclic AMP phosphodiesterase activity associated with insulin-induced maturation is involved in the growth-promoting actions ofrasoncogene products inXenopusoocytes.