Yamaguchi Ryo, Yamagata Kazuo, Ikawa Masahito, Moss Stuart B, Okabe Masaru
Genome Information Research Center, Pharmaceutical Sciences, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
Biol Reprod. 2006 Nov;75(5):760-6. doi: 10.1095/biolreprod.106.052977. Epub 2006 Jul 26.
Male mice deficient for the calmegin (Clgn) or the angiotensin-converting enzyme (Ace) gene show impaired sperm migration into the oviduct and loss of sperm-zona pellucida binding ability in vitro. Since CLGN is a molecular chaperone for membrane transport of target proteins and ACE is a membrane protein, we looked for ACE on the sperm membranes from Clgn-/- mice. ACE was present and showed normal activity, indicating that CLGN is not involved in transporting ACE to the sperm membranes. The ablation of the Adam2 and Adam3 genes generated animals whose sperm did not bind the zona pellucida, which led us to examine the presence of ADAM2 and ADAM3 in Clgn-/- and Ace-/- sperm. ADAM3 was absent from Clgn-/- sperm. In the Ace-/- mice, while ADAM2 was found normally in the sperm, ADAM3 disappeared from the Triton X-114 detergent-enriched phase after phase separation, which suggests that ACE is involved in distributing ADAM3 to a location where it can participate in sperm-zona pellucida binding. This diminished amount of ADAM3 in the Triton X-114 detergent-enriched phase may explain the inability of Clgn-/- and Ace-/- sperm to bind to the zona pellucida.
缺乏钙连接蛋白（Clgn）或血管紧张素转换酶（Ace）基因的雄性小鼠表现出精子向输卵管迁移受损以及体外精子与透明带结合能力丧失。由于CLGN是靶蛋白膜转运的分子伴侣，而ACE是一种膜蛋白，我们在Clgn基因敲除小鼠的精子膜上寻找ACE。ACE存在且活性正常，表明CLGN不参与将ACE转运到精子膜上。Adam2和Adam3基因的缺失产生了精子不与透明带结合的动物，这促使我们检测Clgn基因敲除和Ace基因敲除精子中ADAM2和ADAM3的存在情况。Clgn基因敲除精子中不存在ADAM3。在Ace基因敲除小鼠中，虽然精子中正常存在ADAM2，但在相分离后，ADAM3从富含Triton X - 114去污剂的相中消失，这表明ACE参与将ADAM3分布到一个它可以参与精子与透明带结合的位置。富含Triton X - 114去污剂的相中ADAM3量的减少可能解释了Clgn基因敲除和Ace基因敲除精子无法与透明带结合的原因。
