MicroRNA-125 modulates hemocyte proliferation through regulating Astakine expression and participate the disease resistant in Scylla paramamosain

Abstract

The innate immunity is widely regulated by microRNAs (miRNAs) and that miRNA-125 (miR-125) is involved in many diseases and host immune response. This research was aimed to explore how miR-125 regulates innate immunity in Scylla paramamosain when response to pathogen infection. AMO-miR-125 (anti-miRNA-125 oligonucleotide) was applied to specifically inhibit miR-125 in mud crabs. We found that miR-125 induced hemocyte proliferation, enhanced total hemocyte count in the crabs and protected crabs from challenged with white spot syndrome virus (WSSV) and Vibrio parahaemolyticus. Astakine regulates hemocyte proliferation, and the expression of Astakine increased after miR-125 knockdown, the results indicated that miR-125 may regulate hemocyte proliferation and total hemocyte count by regulating the expression of Astakine. Moreover, miR-125 knockdown also reduced phagocytosis and apoptosis, showing that miR-125 could affect the two processes in crab hemocytes. And the cumulative mortality of WSSV or V. parahaemolyticus infected crabs increased after AMO-miR-125 treatment, which indicated that miR-125 could reduce the death of crab caused by the pathogens and significantly affect the crab's immune response to pathogen. In summary, our data confirmed that miR-125 participates in hemocyte proliferation, the innate immunity, and the resistance to microbial disease in Scylla paramamosain.