TESTIS SPECIFIC HISTONE BINDING PROTEIN (NASP)

项目描述（由申请人提供）：本研究项目的目标是 了解组蛋白结合蛋白NASP的结构和功能 （核自身抗原精子蛋白）。以前NASP被认为是一个 睾丸和精子特异性蛋白;然而，在过去的四年里， 申请人已经发现NASP基因被选择性剪接， 表达存在于所有有丝分裂细胞中的体细胞形式（sNASP）。 因此，他目前的假设是，NASP对正常细胞是重要的， 在有丝分裂和减数分裂中起作用。通过转运组蛋白HI变体 进入细胞核，NASP可能参与调节和/或 在DNA合成过程中， 随后的减数分裂前期这项建议的具体目标是：1） 确定NASP和细胞周期之间的关系，在有丝分裂和 减数分裂细胞这一目标将检验NASP是必要的假设， 通过S期的进展，并在精子发生过程中， 组蛋白/过渡蛋白/鱼精蛋白交换所需，2）确定 在初级精母细胞、圆形精母细胞、圆形精母细胞和圆形精母细胞中， 精子细胞和未受精的卵母细胞来检验NASP是 滥交，并结合任何组蛋白，过渡蛋白或鱼精蛋白在 睾丸和卵母细胞中的任何组蛋白，3）以确定睾丸和 NASP基因的体细胞形式受到调控，以及4）确定NASP基因是否 茎环结合蛋白（SLBP）和睾丸（t）NASP mRNA，类似于 睾丸特异性组蛋白，独立于DNA复制合成 在精子发生过程中，或者它们是否只是在精子发生结束后持续存在。 最后一个S阶段

Description (provided by applicant): The goal of this research project is to understand the structure and function of the histone binding protein NASP (nuclear autoantigenic sperm protein). Previously NASP was thought to be a testis and sperm specific protein; however, over the past four years the applicant has discovered that the NASP gene is alternatively spliced to express a somatic form (sNASP) that is present in all mitotic cells. Consequently, his current hypothesis is that NASP is important for normal cell function during both mitosis and meiosis. By transporting histone HI variants into the nucleus, NASP is likely to participate in the regulation and/or reorganization of chromatin structure during both DNA synthesis and in subsequent meiotic prophases. The specific aims of this proposal are: 1) to determine the relationship between NASP and the cell cycle in both mitotic and meiotic cells. This aim will test the hypothesis that NASP is required for progression through S-phase and that during spermatogenesis it is further required for histone/transition protein/protamine exchange, 2) to determine which specific histones are bound to NASP in primary spermatocytes, round spermatids and unfertilized oocytes to test the hypothesis that NASP is promiscuous and binds any histone, transition protein or protamine in the testis, and any histone in the oocyte, 3) to determine how the testicular and somatic forms of the NASP gene are regulated, and 4) to determine whether the stem loop binding protein (SLBP) and testicular (t)NASP mRNAs, similar to the testis-specific histones, are synthesized independently of DNA replication during spermatogenesis or whether they simply persist after the end of the last S-phase.