Proteome Analysis Of Infertility And High-fertility Sperm By Two-dimensional Difference Gel Electrophoresis And Mass Spectrometry

Introduction: In this study, we performed a comparative analysis of sperm proteins found in high and low-fertility sperm using the novel technique two-dimensional differential in-gel electrophoresis (2-D DIGE) .Thus it is of great research interest to identify a group of consistently changing proteins whose function may reveal insight into critical events in fertile progression and which may hold value as potential therapeutic targets。Material & methods: sperm samples were obtained from 20 sperm donors and by masturbation after 4-6 days abstinence. 10 of them whose sperm failed in 15 AID cycles. The others' sperm succeeded in 50% AID cycles.In this work, two-dimensional difference gel electrophoresis (2-D DIGE) coupled with mass spectrometry (MS) was used to investigate changes in the proteome of human high and low-fertility sperm. In one gel, Cy5-labeled proteins from the infertility sperm were combined with Cy3-labeled proteins isolated from the high-fertility sperm and separated on the same 2-D gel along with a Cy2-labeled mixture of all samples as an internal standard. In the other gel, we labeled the sample reversed.Results: In this study, Over 45 protein spots were analyzed in each paired high/low comparison, and using DIGE technology with the mixed-sample internal standard, 45 protein spots were identified by ms/ms as showing significant change(paired t-test, p<0.05) in the level of expression between high fertility and infertility sperm. 21 proteins were up-regulated and 24 proteins were down-regulated in infertility sperm. They seem to play important roles in a variety of pathways including cell movement, energy metabolism, and cell cytoskeleton.