Altered phosphorylation of a 91-kDa protein in particulate fractions of rat kidney after protracted 1,25-dihydroxyvitamin D3 or estrogen treatment.
Altered phosphorylation of a 91-kDa protein in particulate fractions of rat kidney after protracted 1,25-dihydroxyvitamin D3 or estrogen treatment.
复制标题
长期 1,25-二羟基维生素 D3 或雌激素治疗后，大鼠肾脏颗粒部分中 91-kDa 蛋白质的磷酸化发生改变。
DOI：
10.1006/abbi.1997.0354
复制
发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Walters,MR
中科院分区：
文献类型：
--
作者：
Qin,X;Siaw,EK;Cheung,A;Walters,MR
在维生素D缺乏（−D）大鼠中，1，25-二羟基维生素D3[1，25（OH）2D 3]治疗导致肾脏颗粒部分中91-kDa蛋白（PP-D91）磷酸化的剂量依赖性降低。本文对最近报道的1，25（OH）_2D_3效应进行了详细的研究。与预期的快速信号转导事件模式相反，时间过程（4 h-7 d）实验表明，PP-D91磷酸化直到1，25（OH）2D 3处理3-5 d才降低，导致PP-D91磷酸化在7 d时降低61 ± 3%（P<0.01，n = 3）。这些效应包括1，25（OH）2D 3治疗0天和7天后血浆钙分别从9.3 ± 0.6 mg/dl增加到13.9 ± 0.7 mg/dl。亚细胞分级显示，肾脏PP-D91主要定位于粗线粒体和微粒体组分中，并受1，25（OH）2D 3调节。此外，PP-D91存在于近端和远端肾小管节段的富集制剂中，并受1，25（OH）2D 3调节。组织分布研究表明，PP-D91主要存在于肾脏中，1，25（OH）2D 3受到调节，尽管在肺和心脏中观察到低水平的类似大小的维生素D非依赖性磷酸化条带。与1，25（OH）2D 3相比，雌二醇-17 B治疗（1 mg/天× 7天）显著（P< 0.01）增加了−D和+D大鼠肾脏中PP-D91的磷酸化（分别增加118.5 ± 10.6%和81.9 ± 6.3%）。PP-D91磷酸化，分离和蛋白水解后磷酸化氨基酸分析表明，这些激素alter 32 P纳入磷酸丝氨酸残基。总之，1，25（OH）2D 3降低大鼠肾脏颗粒组分中PP-D91磷酸化的作用是一种持久的组织特异性作用，与该模型中血浆钙水平升高平行。此外，肾脏PP-D91磷酸化受1，25（OH）2D 3与E2处理的差异调节，并发生在磷酸丝氨酸残基上。PP-D91磷酸化降低与1，25（OH）2D 3诱导的高钙血症之间的平行关系可能表明PP-D91在高维生素D血症的肾脏反应中发挥作用。
1,25-Dihydroxyvitamin D3[1,25(OH)2D3] treatment in vitamin D-deficient (−D) rats results in a dose-dependent decrease in phosphorylation of a 91-kDa protein (PP-D91) in particulate fractions of the kidney. This recently reported 1,25(OH)2D3effect was examined in detail herein. In contrast to the pattern expected of a rapid signal transduction event, time course (4 h–7 days) experiments demonstrated that PP-D91 phosphorylation was not decreased until 3–5 days 1,25(OH)2D3treatment, resulting in a 61 ± 3% (P< 0.01,n= 3) decrease in PP-D91 phosphorylation by 7 days. These effects paralleled increases in plasma calcium from 9.3 ± 0.6 to 13.9 ± 0.7 mg/dl after 0 vs 7 days 1,25(OH)2D3treatment, respectively. Subcellular fractionation demonstrated that the renal PP-D91 was predominantly localized and 1,25(OH)2D3-regulated in crude mitochondrial and microsomal fractions. Further, PP-D91 was present and 1,25(OH)2D3-regulated in enriched preparations of both proximal and distal renal tubule segments. Tissue distribution studies demonstrated that the PP-D91 was predominantly present and 1,25(OH)2D3regulated in the kidney, although low levels of a vitamin D-independent phosphorylated band of similar size were observed in the lung and heart. In contrast to 1,25(OH)2D3, estradiol-17B treatment (1 mg/day × 7 day) significantly (P< 0.01) increased PP-D91 phosphorylation in kidney of both −D and +D rats (increased 118.5 ± 10.6 and 81.9 ± 6.3%, respectively). Phosphoamino acid analysis after PP-D91 phosphorylation, isolation, and proteolysis indicated that these hormones alter32P incorporation into phosphoserine residues. In conclusion, the 1,25(OH)2D3effect to reduce PP-D91 phosphorylation in particulate fractions of the rat kidney is a protracted, tissue-specific effect which parallels elevated plasma calcium levels in this model. Moreover, renal PP-D91 phosphorylation is differentially regulated by 1,25(OH)2D3vs E2treatment and occurs on phosphoserine residues. The parallel between decreased PP-D91 phosphorylation and 1,25(OH)2D3-induced hypercalcemia may suggest a role for PP-D91 in the renal response to hypervitaminosis D.