Testis-specific gene C7orf61 is involved in mouse sperm–egg fusion

The present study aimed to investigate the expression of chromosome 7 open reading frame 61 (C7orf61) in the testis and determine its role in spermatogenesis. Reverse transcription–quantitative polymerase chain reaction, Western blot and immunofluorescence were performed to evaluate the expression characteristics of C7orf61 in mice and humans. In vitro fertilization assay was used to determine the role of the C7ORF61 protein in sperm-egg fusion. The results demonstrated that C7orf61 was a testis-specific gene; the C7ofr61 mRNA expression level sharply increased in the fourth postnatal week and gradually increased until the adult stage. The C7ORF61 protein was located throughout the subacrosomal area and close to the nucleus in both mouse and human sperm. The incubation with the C7ORF61 antibody significantly decreased the fertilization rate of mouse eggs. The present findings suggested that the C7ORF61 protein might be involved in sperm–egg fusion, and could serve as a useful target for contraceptives. However, further research is still needed to know the detailed molecular mechanism of its role.本研究旨在探究7号染色体开放阅读框61（chromosome 7 open reading frame 61，C7orf61）在睾丸中的表达情况，并明确其在精子发生过程中的作用。研究采用逆转录定量聚合酶链反应（reverse transcription–quantitative polymerase chain reaction）、蛋白质免疫印迹（Western blot）及免疫荧光（immunofluorescence）技术，对C7orf61在小鼠与人类样本中的表达特征进行评估；通过体外受精（in vitro fertilization）实验，探究C7ORF61蛋白在精卵融合过程中的功能。结果显示，C7orf61属于睾丸特异性基因，其mRNA表达水平在出生后第4周显著升高，并逐步上升直至成年阶段；C7ORF61蛋白在小鼠及人类精子中，均定位于顶体下区域并紧贴细胞核。使用C7ORF61抗体进行孵育处理，可显著降低小鼠卵子的受精率。本研究结果表明，C7ORF61蛋白可能参与精卵融合过程，可作为潜在的避孕靶标。但该蛋白发挥作用的具体分子机制，仍需后续研究进一步阐明。