Differential expression of two gamma-tubulin isoforms during gametogenesis and development in Drosophila
Differential expression of two gamma-tubulin isoforms during gametogenesis and development in Drosophila
复制标题
DOI：
10.1006/dbio.1997.8545
复制
发表时间：
1997-04-15
影响因子：
2.7
通讯作者：
Fuller, MT
中科院分区：
文献类型：
--
作者：
Wilson, PG;Zheng, Y;Fuller, MT
先前的工作在果蝇中发现了一个γ -微管蛋白基因，γ Tub23C （Zheng et al., 1991）。我们现在报告鉴定第二个γ -微管蛋白基因，γ Tub37CD。免疫印迹分析和免疫定位表明，gamma Tub37CD和gamma Tub23C在配子发生和发育过程中存在差异表达。在卵发生过程中，在有丝分裂生殖细胞的中心体和细胞质中检测到γ Tub23C，但在有丝分裂完成后的生殖细胞中未检测到。相反，在增殖的生殖细胞中未检测到γ Tub37CD，但在卵室发育过程中似乎在生殖细胞中积累。在发育中的卵母细胞的前后两极均未检测到γ -微管蛋白异构体。在精子发生过程中，只有gamma Tub23C在中心体中被检测到，在那里它表现出细胞周期和分化依赖的组织。在进入第一次减数分裂的过程中，gamma Tub23C在中心粒处被组织成一个微粒焦点，直到减数分裂II完成。在减数分裂后精子细胞分化过程中，gamma Tub23C首先以棒状结构出现，然后在细胞核和细长鞭毛交界处附近出现环状结构，但在成熟精子束中未发现。由麻绳编码的种系特异性CDC25是将gamma Tub23C组织到精母细胞的小体聚焦所必需的，但对于m期中心粒对的分离或gamma Tub23C在中心粒的减数分裂后组织则不需要。在受精时重建一个标准中心体后，在合胞胚胎的中心体中仅检测到gamma Tub37CD，而在细胞化胚胎的中心体中检测到gamma Tub37CD和gamma Tub23C。这两种同工异构体的共定位表明，gamma Tub23C和gamma Tub37CD都含有定位到中心体所必需的gamma小管蛋白的结构特征。(C) 1997学术出版社。
Previous work identified a gamma-tubulin gene, gamma Tub23C, in Drosophila (Zheng et al., 1991). We now report identification of a second gamma-tubulin gene, gamma Tub37CD. Immunoblot analysis and immunolocalization show that gamma Tub37CD and gamma Tub23C are differentially expressed during gametogenesis and development. During oogenesis, gamma Tub23C was detected at centrosomes and in the cytoplasm of mitotic germ cells, but was not detected in germ cells following completion of mitosis. Conversely, gamma Tub37CD was not detected in proliferating germ cells, but appeared to accumulate in germ cells during egg chamber development. Neither gamma-tubulin isoform was detected at the anterior or posterior poles of developing oocytes. During spermatogenesis, only gamma Tub23C was detected at centrosomes, where it showed cell cycle- and differentiation-dependent organization. During the transition into the first meiotic division, gamma Tub23C became organized as a corpuscular focus at centrioles until completion of meiosis II. During postmeiotic spermatid differentiation, gamma Tub23C was detected first as a rod and then as a collar-like structure near the juncture of the nucleus and the elongating flagellum, but was not detected in bundles of mature sperm. The germline-specific CDC25 encoded by twine is required for organization of gamma Tub23C into corpuscular focus in spermatocytes, but not for separation of centriole pairs in M-phase or postmeiotic organization of gamma Tub23C at centrioles. Following reconstitution of a canonical centrosome at fertilization, only gamma Tub37CD was detected at centrosomes in syncytial embryos, but both gamma Tub37CD and gamma Tub23C were detected at centrosomes in cellularized embryos. Colocalization of these two isoforms suggests that gamma Tub23C and gamma Tub37CD both contain structural features of gamma-tubulins essential for localization to centrosomes. (C) 1997 Academic Press.