Hu Chengqing, Shi Jiangcheng, Chi Yujing, Yang Jichun, Cui Qinghua
Center for Noncoding RNA Medicine, Department of Physiology and Pathophysiology, Department of Biomedical Informatics, MOE Key Laboratory of Cardiovascular Sciences, School of Basic Medical Sciences, Peking University, 38 Xueyuan Rd, Beijing 100191, China.
Department of Central Laboratory & Institute of Clinical Molecular Biology, Peking University People's Hospital, Beijing 100044, China.
Life (Basel). 2021 Nov 11;11(11):1219. doi: 10.3390/life11111219.
The sex chromosomes play central roles in determining the sex of almost all of the multicellular organisms. It is well known that meiosis in mammalian spermatogenesis produces ~50% Y- and ~50% X-chromosome-bearing sperm, a 1:1 ratio. Here we first reveal that the X-chromosome-encoded miRNAs show lower expression levels in the left testis than in the right testis in healthy mice using bioinformatics modeling of miRNA-sequencing data, suggesting that the Y:X ratio could be unbalanced between the left testis and the right testis. We further reveal that the Y:X ratio is significantly elevated in the left testis but balanced in the right testis using flow cytometry. This study represents the first time the biased Y:X ratio in the left testis but not in the right testis is revealed.
性染色体在几乎所有多细胞生物的性别决定中起着核心作用。众所周知，哺乳动物精子发生过程中的减数分裂会产生约50%携带Y染色体和约50%携带X染色体的精子，比例为1:1。在这里，我们首先利用miRNA测序数据的生物信息学建模揭示，在健康小鼠中，X染色体编码的miRNA在左睾丸中的表达水平低于右睾丸，这表明左睾丸和右睾丸之间的Y:X比例可能不平衡。我们进一步利用流式细胞术揭示，左睾丸中的Y:X比例显著升高，而右睾丸中的比例是平衡的。这项研究首次揭示了左睾丸而非右睾丸中存在偏向性的Y:X比例。
