Lcn8, also known as mEP17, is a member of the lipocalin family. It is specifically expressed in the initial segment of the mouse caput epididymis. Lcn8 is likely involved in maintaining sperm quality during epididymal sperm maturation, which is crucial for male fertility [1,2,3]. Mouse models are valuable for studying Lcn8's function in vivo.

In Lcn8 knockout (KO) mice, the number of morphologically abnormal sperm in the cauda epididymis significantly increased, the proportion of progressive motility sperm decreased, the proportion of immobilized sperm rose, and the sperm spontaneous acrosome reaction (AR) frequency increased. This indicates that Lcn8 deficiency leads to epididymal sperm maturation defects [1]. In addition, the quadruple knockout (including Lcn8) and quintuple knockout male mice of lipocalin family genes showed subfertility and infertility respectively, with reduced amounts of ADAM3, an essential protein for sperm binding to the zona pellucida [2].

In conclusion, Lcn8 plays a vital role in maintaining sperm quality and ensuring proper epididymal sperm maturation. The use of Lcn8 KO mouse models has revealed its significance in male fertility-related processes, contributing to our understanding of the molecular mechanisms underlying sperm maturation and male sub-fertility [1,2].

References:

1. Wen, Zongzhuang, Liu, Dongyue, Zhu, Haixia, Ye, Chao, Gao, Jiangang. 2021. Deficiency for Lcn8 causes epididymal sperm maturation defects in mice. In Biochemical and biophysical research communications, 548, 7-13. doi:10.1016/j.bbrc.2021.02.052. https://pubmed.ncbi.nlm.nih.gov/33631677/

2. Sakurai, Nobuyuki, Fujihara, Yoshitaka, Kobayashi, Kiyonori, Ikawa, Masahito. 2022. Nuclease technology-mediated disruption of lipocalins, Ly6g5b, and Ly6g5c causes male subfertility in mice. In Andrology, 12, 981-990. doi:10.1111/andr.13350. https://pubmed.ncbi.nlm.nih.gov/36428102/

3. Suzuki, Kichiya, Lareyre, Jean-Jacques, Sánchez, Diego, Matusik, Robert J, Orgebin-Crist, Marie-Claire. . Molecular evolution of epididymal lipocalin genes localized on mouse chromosome 2. In Gene, 339, 49-59. doi:. https://pubmed.ncbi.nlm.nih.gov/15363845/