FERNANDINO Juan Ignacio
congresos y reuniones científicas
N-myc downstream-regulated gene-1b (Ndrg1b) regulates the gonocytes type II proliferation in medaka (Oryzias latipes).
ARIAS PADILLA, L.F.; FERNANDINO, J.I.
Congreso; X Latin American Society for Developmental Biology Meeting.; 2019
Latin American Society for Developmental Biology
The development of a functional gonad is a multi-step process that includes migration, proliferation, differentiation and renewal, ending in the production of sperm or oocytes. After primordial germ cells (PGCs) reach the gonads, their number increase to become gametogenesis-competent germ cells (gonocytes) by two types of proliferations. Type I corresponds to a self-renewal division, typical of stem cells. Meanwhile, in the type II proliferation, the PGCs are divided mitotically synchronously and successively to form cysts, and subsequently enter meiosis. Specifically for medaka, the female meiosis begins at hatching stage, while in males at 20 days post hatching. Proliferation defects may lead to sex abnormalities including infertility and sex reversal. N-myc downstream-regulated gene-1b (Ndrg1b) has been characterized like a proliferation regulator in several biological processes. We observed that ndrg1b was down-regulated during type II proliferation of both sexes. Then, we analyzed the bi-allelic ndrg1b mutants, generated by CRISPR/Cas9, observing a reduction of proliferative markers (PCNA and PH3), and less cyst number in both sexes (germ cell marker, VASA), which is related with alterations on type II proliferation. Although males and females reached adulthood normally, the reproductive parameters like spawning, fecundity and hatching in both sexes were altered; providing clear evidences of the role of ndrg1b in the regulation of the gonocytes type II proliferation.