1. Academic Validation
  2. Low levels of PRSS37 protein in sperm are associated with many cases of unexplained male infertility

Low levels of PRSS37 protein in sperm are associated with many cases of unexplained male infertility

  • Acta Biochim Biophys Sin (Shanghai). 2016 Nov;48(11):1058-1065. doi: 10.1093/abbs/gmw096.
Jianbing Liu 1 2 Chunling Shen 3 Weimin Fan 4 Yan Chen 2 Aijun Zhang 4 Yun Feng 4 Zheng Li 5 Ying Kuang 6 Zhugang Wang 3 2 6
Affiliations

Affiliations

  • 1 State Key Laboratory of Medical Genomics, Research Center for Experimental Medicine, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai 200025, China.
  • 2 Model Organism Division, E-Institutes of Shanghai Universities, SJTUSM , Shanghai 200025, China.
  • 3 State Key Laboratory of Medical Genomics, Research Center for Experimental Medicine, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai 200025, China zhugangw@shsmu.edu.cn clshen@139.com.
  • 4 Reproductive Medical Center of Ruijin Hospital , Shanghai 200025, China.
  • 5 Shanghai Human Sperm Bank of Shanghai Renji Hospital , Shanghai 200025, China.
  • 6 Shanghai Research Center for Model Organisms , Shanghai 201203, China.
Abstract

PRSS37, a putative trypsin-like serine protease, is highly conserved during mammalian evolution as revealed by multiple sequence alignment. Mice deficient for Prss37 gene exhibit male infertility, but their mating behavior, spermatogenesis, sperm morphology, and motility remain unaffected, similar to a situation called unexplained male infertility (UMI) in men (human being). Here, we demonstrated that PRSS37 is restrictively expressed in human testis, where it is mainly located in the elongating and elongated spermatids during spermiogenesis as shown by immunohistochemical analysis of normal human testicular sections. In mature sperm, PRSS37 appears in the acrosome region and diminishes during acrosome reaction. Further examination reveals that PRSS37 contents in sperm from patients with UMI are dramatically lower than those in sperm from men with proven fertility or from sperm donors. Sperm with low PRSS37 contents exhibit abnormal activation of the proacrosin/acrosin system and premature proteolysis of ADAM2, which may impair the functional competence of human sperm in vivo However, the in vitro fertilization outcomes of sperm with low PRSS37 contents are not affected. Together, these data implicate an important role of PRSS37 for male fertility. PRSS37 can be used as a potential molecular biomarker for evaluating sperm fertilization capability in vivo but not in vitro.

Keywords

ACROSIN; ADAM2; PRSS37; semen analysis; unexplained male infertility.

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