Calcium regulation by lens plasma membrane vesicles.
Calcium regulation by lens plasma membrane vesicles.
复制标题
晶状体质膜囊泡对钙的调节。
DOI：
10.1016/0003-9861(88)90312-8
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发表时间：
1988
影响因子：
3.9
通讯作者：
Louis,CF
中科院分区：
文献类型：
--
作者：
Galvan,A;Louis,CF
用小牛晶状体囊泡制剂研究了质膜在调节透镜纤维细胞胞浆Ca 2+浓度中的作用。这些囊泡的钙积累是ATP依赖性的，并可通过离子载体A23187释放，表明钙被转运到囊泡空间。Ca 2+（K12 = 0.08 μ mCa 2+）、钾离子（最大浓度为50 mMK+）和cAMP依赖性蛋白激酶可刺激钙的积累，钒酸盐（IC 50= 5 μM）和钙调蛋白抑制剂R24571（IC 50= 5 μM）可抑制钙的积累，表明钙泵是质膜来源的，可能依赖于钙调蛋白。缬氨霉素，在K+的存在下，刺激钙的摄取，这表明钙泵要么countertransports K+，或在生电的方式进行调节。亚硒酸盐和对氯汞苯甲酸盐对钙吸收的抑制表明该酶中存在必需的SH基团。从钙填充的透镜囊泡的钙释放被Na+增强，表明这些囊泡也包含Na：Ca交换载体。对氯汞苯甲酸盐和对氯汞苯甲酸盐磺酸也促进了钙从充满钙的囊泡中的释放，这表明这种释放与钙的吸收一样，部分是由含半胱氨酸的蛋白质介导的。结果表明，透镜纤维细胞内Ca 2+浓度受多种质膜过程的调节。钙摄取和释放对-SH试剂的敏感性在透镜白内障形成中具有意义，其中透镜蛋白的氧化被认为是这种情况下胞质Ca 2+升高的原因。
The role of the plasma membrane in the regulation of lens fiber cell cytosolic Ca 2+ concentration has been examined using a vesicular preparation derived from calf lenses. Calcium accumulation by these vesicles was ATP dependent, and was releasable by the ionophore A23187, indicating that calcium was transported into a vesicular space. Calcium accumulation was stimulated by Ca 2+(K 1 2= 0.08 μm Ca 2+) potassium (maximally at 50 mM K+), and cAMP-dependent protein kinase; it was inhibited by both vanadate (IC 50= 5 μM) and the calmodulin inhibitor R24571 (IC 50= 5 μM), indicating that this pump was plasma-membrane derived and likely calmodulin dependent. Valinomycin, in the presence of K+, stimulated calcium uptake, suggesting that the calcium pump either countertransports K+, or is regulated in an electrogenic fashion. Inhibition of calcium uptake by selenite and p-chloromercuribenzoate demonstrates the presence of an essential-SH group (s) in this enzyme. Calcium release from calcium-filled lens vesicles was enhanced by Na+, demonstrating that these vesicles also contain a Na: Ca exchange carrier. p-Chloromercuribenzoate and p-chloromercuribenzoate sulfonic acid also promoted calcium release from calcium-filled vesicles, suggesting that this release, like calcium uptake, is in part mediated by a cysteine-containing protein. We conclude that lens fiber cell cytosolic Ca 2+ concentration could be regulated by a number of plasma membrane processes. The sensitivity of both calcium uptake and release to-SH reagents has implications in lens cataract formation, where oxidation of lens proteins has been proposed to account for the elevated cytosolic Ca 2+ in this condition.
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天然和重构钙运输系统中的钙调蛋白 *
影响因子：
5.2
作者：
E. Carafoli;V. Niggli;K. Malmström;P. Caroni
通讯作者：
P. Caroni
心脏肌膜的 Ca2 泵 ATP 酶。
影响因子：
4.8
作者：
P. Caroni;E. Carafoli
通讯作者：
E. Carafoli
晶状体中的钙传输。
影响因子：
4.4
作者：
Hightower,KR;Leverenz,V;Reddy,VN
通讯作者：
Reddy,VN
埃默里小鼠晶状体中钠钾依赖性 ATP 酶活性。
影响因子：
2
作者：
Unakar,NJ;Tsui,JY;Kuck,JF;Kuck,KD
通讯作者：
Kuck,KD
DOI：
10.1016/0304-4157(76)90004-6
发表时间：
1976-01-01
期刊：
BIOCHIMICA ET BIOPHYSICA ACTA
影响因子：
--
作者：
BENEDETTI, EL;DUNIA, I;BLOEMENDAL, H
通讯作者：
BLOEMENDAL, H