hypoxia impairs primordial germ cell migration in zebrafish (danio rerio) embryos在斑马鱼缺氧损害原生殖细胞迁移(鲐鱼类)的胚胎.pdfVIP

Hypoxia Impairs Primordial Germ Cell Migration in Zebrafish (Danio rerio) Embryos 1,2 1,2 3 1,2 ¤ Kwok Hong Lo , Michelle Nga Yu Hui , Richard Man Kit Yu , Rudolf Shiu Sun Wu * , Shuk Han Cheng1,2* 1 Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China, 2 The State Key Lab in Marine Pollution, Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China, 3 School of Environmental and Life Sciences, The University of Newcastle, Callaghan, Australia Abstract Background: As a global environmental concern, hypoxia is known to be associated with many biological and physiological impairments in aquatic ecosystems. Previous studies have mainly focused on the effect of hypoxia in adult animals. However, the effect of hypoxia and the underlying mechanism of how hypoxia affects embryonic development of aquatic animals remain unclear. Methodology/Principal Findings: In the current study, the effect of hypoxia on primordial germ cell (PGC) migration in zebrafish embryos was investigated. Hypoxic embryos showed PGC migration defect as indicated by the presence of mis- migrated ectopic PGCs. Insulin-like growth factor (IGF) signaling is required for embryonic germ line development. Using real-time PCR, we found that the mRNA expression levels of insulin-like growth factor binding protein (IGFBP-1), an inhibitor of IGF bioactivity, were significantly increased in hypoxic embryos. Morpholino knockdown of IGFBP-1 rescued the PGC migration defect phenotype in hypoxic embryos, suggesting the role of IGFBP-1 in inducing PGC mis-migration. Conclusions/Significance: This study provides novel evidence t