Fig. 5

Regulation of ovulation-related genes by LH signaling in npr^+/+ and npr^-/- fish.

(a) The timescale of hCG-induced oocyte maturation and ovulation in npr^+/+ zebrafish. Follicles were isolated at different time points after hCG (10 IU/µl) injection. Matured follicle with transparent appearance is indicated by black arrow and ovulated oocyte with enlarged fertilization membrane is indicated by white arrow. (b) The expression profile of npr after hCG injection. (c) The expression profile of ovulation related genes in npr^+/+ and npr^/ fish after hCG injection. (i) Genes involved in prostaglandin biosynthesis; mmps and tissue inhibitors of metalloproteinases (timp2b); (iii) Genes involved in steroidogenesis; (iv) A disintegrin and metalloprotease with thrombospondin motifs1 (adamts1) and (v) cathepsin L (ctsl). The expression levels were normalized to that of ef1α and then to the expression level in npr^+/+ fish at 0 h. Different letters in each dataset indicated statistical significance (P < 0.05). Each value represents the mean value ± SEM (n = 4) of three independent experiments (*P < 0.05; **P < 0.01; ***P < 0.001 vs npr^+/+).