Controlling of Reproductive Organs Maturation in Shrimp

Abstract

Ribosomal protein was known to play a function in protein synthesis. Recently, many studies reported the extraribosomal activity including DNA repair, apoptosis, regulation of translation, controlling of development and red blood cell development. Ribosomal protein L10a (Rpl10a) encoded by the rpl10a gene has been reported the secondary function during embryogenesis, organogenesis and ovarian development. In this study, the activity of Rpl10a protein on reproductive organs development was investigated. The recombinant His-Rpl10a protein (rRpl10a) was injected into shrimps to promote the ovarian development in shrimps. The concentration at 180 μg of His-rRpl10a per shrimp was the effective dose to stimulate ovaries to reach to stages I and II of ovarian maturation within 7 days post injection. In addition, the spermatogenesis in shrimp and mouse were stimulated by His-rRpl10a protein in vitro. The early stage marker gene expressions (Dmrt1 in shrimp or Rhau in mouse) were decreased, while Prm2, late-stage marker gene was upregulated. The cell proliferation was also confirmed in rRpl10a treated testis. Furthermore, the other functions of rpl10a on anemia using rpl10a mutant zebrafish (Danio rerio) as a model were also studied. The rpl10a-deficient embryos displayed the abnormality phenotypes including thinner yolk extension, smaller eyes, shorter body length and bent tail at 25 hpf (hour-post fertilization). Besides, rpl10a gene deficiency showed the phenotypes as a bigger yolk sac, edema, smaller eyes, melanophore pigment reduction, and a curved tail at 50 hpf. These morphological abnormalities were recovered by rpl10a full-length mRNA. This result indicated that rpl10a gene is essential for early embryogenic development. Moreover, loss activity of rpl10a affected growth retardation and embryonic lethality within 3-7 dpf. Anemic phenotype and hemoglobin activity were observed both knockdown and knockout model. The hemoglobin marker genes including gata1, hbae3, and hbbe1 have declined expression, whereas tp53 transcript was increased. These findings supported that Rpl10a protein might play an extra-function in anemia. Knockdown of rpl10a gene also affected the low expression of primordial germ cell (PGC) marker genes (nanos1 and vasa) significantly. Interestingly, these findings suggested that Rpl10a protein is necessary on the early stage of reproductive organs development, primordial germ cells development, embryogenesis, and hemoglobin synthesis.