Linkage of photoreceptor degeneration by apoptosis with inherited defect in phototransduction.
Linkage of photoreceptor degeneration by apoptosis with inherited defect in phototransduction.
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DOI：
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发表时间：
1994-02
影响因子：
4.4
通讯作者：
R. Lolley;Hongmei Rong;C. Craft
中科院分区：
文献类型：
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作者：
R. Lolley;Hongmei Rong;C. Craft
目的研究正常小鼠和rd/rd小鼠的视网膜发育情况，以确定编码级联磷酸二酯酶β亚基的视网膜变性（rd）基因的遗传缺陷是否与rd光感受器凋亡变性有关。方法采用分光光度法测定正常视网膜和rd/rd视网膜的DNA含量，并分析其在光感受器变性过程中的差异损失。电镜观察退化的rd光感受器的细胞质特征和染色体凝聚。在rd/rd细胞死亡发生的发育期间，通过琼脂糖凝胶电泳每天间隔分析DNA片段。结果rd/rd视网膜的DNA丢失在出生后10 ~ 15天最大。光感受器细胞在出生后退行性变过程中单独死亡，在形态正常的rd光感受器中分散着嗜核细胞。在rd/rd视网膜中，DNA分裂成200个碱基对倍数最多发生在出生后10至15天。结论：rd/rd视网膜的光感受器细胞死亡的发生机制将光传导级联中的缺陷与细胞死亡程序（称为凋亡）联系起来。
PURPOSE To investigate the developing retina of normal and rd/rd mice to establish if the inherited defect in the retinal degeneration (rd) gene, encoding the beta subunit of the cascade phosphodiesterase, is associated with rd photoreceptor degeneration by apoptosis. METHODS DNA content of developing normal and rd/rd retinas was measured spectrophotometrically and analyzed for differential loss during the course of photoreceptor degeneration. Degenerating rd photoreceptors were evaluated by electron microscopy for cytoplasmic features and chromosomal condensation. DNA fragmentation was analyzed by agarose gel electrophoresis at daily intervals during the developmental period in which rd/rd cell death occurs. RESULTS DNA loss from developing rd/rd retinas is maximal between 10 and 15 postnatal days. Photoreceptor cells die individually throughout the postnatal period of degeneration, with pycnotic nuclei dispersed among morphologically normal rd photoreceptors. DNA fragmentation into 200 base pair multiples occurs maximally in rd/rd retinas between 10 and 15 postnatal days. CONCLUSION Photoreceptor cell death in developing rd/rd retinas occurs by a mechanism that links a defect in the phototransduction cascade with a program for cell death, called apoptosis.