Production of functional sperm from <i>in vitro</i>-cultured premeiotic spermatogonia in a marine fish
Hong Zhang, 中山大学海洋科学学院, 广东 广州510275, 中国, Wanwan Zhang, Chengyu Mo, Mengdan Dong, Kuntong Jia, Wei Liu, Meisheng Yi, 南方海洋科学与工程广东省实验室(珠海), 广东 珠海519000, 中国, 广东省海洋资源与近岸工程重点实验室机构, 广东 广州510000, 中国
Abstract
<i>In vitro</i> production of functional gametes can revolutionize reproduction by reducing generation intervals and accelerating genetic breeding in aquaculture, especially in fish with relatively long generations. Nevertheless, functional sperm production from <i>in vitro</i>-cultured spermatogonia remains a challenge in most aquaculture fish. In this study, we isolated and characterized premeiotic spermatogonia from marine four-eyed sleepers (<i>Bostrychus sinensis</i>), which are prone to ovotesticular or sterile testicular development, and induced the differentiation of the spermatogonia into flagellated sperm in a three-dimensional (3D) culture system. Artificial insemination indicated that the <i>in vitro</i>-derived sperm were capable of fertilizing mature oocytes to develop into normal larvae. Furthermore, melatonin significantly promoted spermatogonia proliferation and differentiation through the ERK1/2 signaling pathway, and thus increased the efficiency in functional sperm production. The 3D culture system and resulting functional sperm hold great promise for improving the genetic breeding of aquaculture fish.