DYNAMICS OF CYCLIC NUCLEOTIDE METABOLISM IN SPERM

一种基于磷酸二酯酶性质的促进P-O的新技术 环3英尺、5英尺核苷酸的水解键断裂 以及将来自[18-O]水的18-O插入到5 足部核苷酸产物将用于监测cAMP的动态和 完整海胆精子中cGMP代谢的研究。通过这一新的分析 最近获得的接近信息表明，此外 涉及蛋白激酶的环核苷酸作用的变构模式 激活时，可能会对某些细胞功能产生影响 与环核苷酸的水解有关。这段关系是 在视觉视网膜中发现，在那里发现光刺激超过 4对数范围的强度促进cGMP水解率的增量增加 流量。这些光诱导的cGMP代谢通量的增加不是 与细胞cGMP稳态水平的任何变化相关联， 这表明cGMP水解率的增加与 CGMP的合成也同样增加。这种cGMP代谢流量的增加 已经被假定为是释放绑定的机制的组成部分 钙。其中描述的实验的一个意图是 建议是确定某些新陈代谢的修饰和 精子中的功能事件也与新披露的 环核苷酸代谢的修饰只能通过 18-O标记程序的代谢测量类型 提供了。获取有关cGMP基本动力学的信息 精子中的cAMP代谢代表了研究的主要目标 被引导了。 海胆精子的几个生物学过程，包括顶体 反应、呼吸、动力和离子传输被激活或引发 由从海胆卵中提取的特定因子。这些蛋的动作 已发现与循环中的改变有关的因素 核苷酸代谢，但环核苷酸的精确参与 影响精子活动的因素尚不清楚。将获得的信息 从18-O标签研究提出的应该有助于提供一些新的 对环核苷酸的作用及其在其基因改变中的作用的见解 新陈代谢可能在调节和/或促进某些细胞 精子中的事件。腺嘌呤和鸟嘌呤18-O标记的测定 完整细胞内的核苷酸α、β和Lambda-磷酸化也 提供了检查整个核苷酸和能量的可能性 代谢与可在这些细胞中促进的过程有关的代谢。

A new technique, based on the property of phosphodiesterases to promote P-O bond cleavage during the hydrolysis of cyclic 3 feet, 5 feet nucleotides and the insertion of 18-O from [18-O]water into the phosphoryls of the 5 feet-nucleotide product will be used to monitor the dynamics of cAMP and cGMP metabolism in intact sea urchin sperm. By this new analytical approach information has recently been obtained indicating that in addition to the allosteric mode of cyclic nucleotide action involving protein kinase activation, there may be an influence on certain cell functions that are related to the hydrolysis of cyclic nucleotides. This relationship was uncoverd in the visual retina where it was found that light stimuli over a 4 log range of intensities promote incremental increases in cGMP hydrolytic flux. These light-induced increases in cGMP metabolic flux were not associated with any changes in cellular cGMP steady state levels, indicating that the increased rate of cGMP hydrolysis is tightly coupled to an equal increase in cGMP synthesis. This increase in cGMP metabolic flux has been postulated to be integral to a mechanism for releasing bound calcium. One of the intensions of the experiments described in this proposal is to determine if the modification of certain metabolic and functional events in sperm are also associated with this newly disclosed modification of cyclic nucleotide metabolism that can only be uncovered by the type of metabolic measurements that the 18-O labeling procedure provides. Obtaining information regarding the fundamental dynamics of cGMP and cAMP metabolism in sperm represents the primary goal of the studies to be conducted. Several biological processes in sea urchin sperm including the acrosome reaction, respiration, motility and ion transport are activated or elicited by specific factors derived from sea urchin eggs. The actions of these egg factors have been found to be associated with alterations in cyclic nucleotide metabolism but the precise involvement of cyclic nucleotides in influencing sperm events is unclear. The information that will be obtained from the 18-O labeling studies proposed should help to provide some new insights into the role that cyclic nucleotides and alterations in their metabolism may play in modulating and/or promoting certain of the cellular events in sperm. The measurement of 18-O labeling of adenine and guanine nucleotide Alpha, Beta, and Lambda-phosphoryls within the intact cells also provides the potential for examining overall nucleotide and energy metabolism in relation to the processes that can be promoted in these cells.