Jamsai Duangporn, Bianco Deborah M, Smith Stephanie J, Merriner Donna J, Ly-Huynh Jennifer D, Herlihy Amy, Niranjan Birunthi, Gibbs Gerard M, O'Bryan Moira K
The Centre for Reproduction and Development and The Centre for Urological Research, Monash Institute of Medical Research, Monash University, 27-31 Wright Street, Clayton, Melbourne, Victoria 3168, Australia.
Reproduction. 2008 Jun;135(6):751-9. doi: 10.1530/REP-07-0485.
Cysteine-rich secretory protein 2 (CRISP2) is a testis-enriched protein localized to the sperm acrosome and tail. CRISP2 has been proposed to play a critical role in spermatogenesis and male fertility, although the precise function(s) of CRISP2 remains to be determined. Recent data have shown that the CRISP domain of the mouse CRISP2 has the ability to regulate Ca(2+) flow through ryanodine receptors (RyR) and to bind to MAP kinase kinase kinase 11 (MAP3K11). To further define the biochemical pathways within which CRISP2 is involved, we screened an adult mouse testis cDNA library using a yeast two-hybrid assay to identify CRISP2 interacting partners. One of the most frequently identified CRISP2-binding proteins was gametogenetin 1 (GGN1). Interactions occur between the ion channel regulatory region within the CRISP2 CRISP domain and the carboxyl-most 158 amino acids of GGN1. CRISP2 does not bind to the GGN2 or GGN3 isoforms. Furthermore, we showed that Ggn1 is a testis-enriched mRNA and the protein first appeared in late pachytene spermatocytes and was up-regulated in round spermatids before being incorporated into the principal piece of the sperm tail where it co-localized with CRISP2. These data along with data on RyR and MAP3K11 binding define the CRISP2 CRISP domain as a protein interaction motif and suggest a role for the GGN1-CRISP2 complex in sperm tail development and/or motility.
富含半胱氨酸的分泌蛋白2（CRISP2）是一种在睾丸中高度富集的蛋白质，定位于精子顶体和尾部。尽管CRISP2的确切功能仍有待确定，但已有研究提出它在精子发生和男性生育中起关键作用。最近的数据表明，小鼠CRISP2的CRISP结构域具有调节钙离子通过兰尼碱受体（RyR）流动以及与丝裂原活化蛋白激酶激酶激酶11（MAP3K11）结合的能力。为了进一步确定CRISP2所涉及的生化途径，我们利用酵母双杂交试验筛选成年小鼠睾丸cDNA文库，以鉴定与CRISP2相互作用的蛋白。最常被鉴定出的与CRISP2结合的蛋白之一是配子生成素1（GGN1）。CRISP2的CRISP结构域内的离子通道调节区域与GGN1的最羧基端158个氨基酸之间发生相互作用。CRISP2不与GGN2或GGN3异构体结合。此外，我们发现Ggn1是一种在睾丸中高度富集的mRNA，其蛋白质最早出现在粗线期晚期精母细胞中，并在圆形精子细胞中上调，然后被整合到精子尾部的主段，在那里它与CRISP2共定位。这些数据以及关于RyR和MAP3K11结合的数据将CRISP2的CRISP结构域定义为一种蛋白质相互作用基序，并提示GGN1-CRISP2复合物在精子尾部发育和/或运动中发挥作用。
