Temporal expression of c-kit in spermatogenesis of two grasshopper species

Abstract Two species of grasshoppers, Calliptamus abbreviatus (Ikonn.) and Shirakiacris shirakii (I. Bol.), were collected randomly in the Siping area of Jilin Province, China. By using immunohistochemical methods and statistical analysis, we observed and compared the temporal expression of c-kit protein in four representative stages of spermatogenesis of the two grasshoppers, namely: spermatogonia; primary spermatocyte; secondary spermatocyte; and mature sperm. Results showed that there was c-kit positive temporal expression at each stage of spermatogenesis, but there were different positive expression levels: (i) weak positive expression of c-kit protein appeared in spermatogonia and the positive granules were thinner; (ii) strong positive expression of c-kit protein existed in primary spermatocyte and positive granules became biggest among all developmental stages; (iii) c-kit positive expression stayed stronger in secondary spermatocyte while positive granules became thinner; (iv) there was a strong positive expression of c-kit and thinner positive granules in mature sperm, which distributed on head and tail; (v) the biggest c-kit positive granules had been found massing at the end of spermary; and (vi) significant differences of c-kit positive expression existed in spermatogenesis between two species of grasshoppers. The results indicated that c-kit protein may play a crucial role in spermatogenesis and even retain the physiological action of sperms and fertilization in grasshoppers.