RNAi effect of <i>BmTGIF</i>-specific siRNA-4.

<p>(A) Effect of injecting <i>BmTGIF</i>-specific siRNA-4 into silkworm larvae at the beginning of the third, fourth and fifth instars. Relative amounts of <i>BmTGIF</i> mRNA in blank control, NC and <i>BmTGIF</i>-siRNA-4 groups were analyzed by Q-PCR at day 3 of fifth instar in triplicate, the <i>BmTGIF</i> mRNA level was normalized against the housekeeping cytoplasmic β−actin mRNA level. Lower panel represents BmTGIF protein detected in blank control, NC and <i>BmTGIF</i>-siRNA-4 group by western blotting using BmTGIF-L antibody, corresponding lanes marked by 1, 2, and 3, respectively. (B) A concise schematic showing the progression of spermatogenesis in <i>B. mori</i>. Spermatogonium born at the apical tip of first instar surround the teloblast, they undergo six rounds of synchronous mitotic divisions to produce cysts of 64 primary spermatocysts, the primary spermatocysts then enter an extended G2 phase characterized by a little increase in cell volume followed by the first meiotic division to produce larger cysts of secondary spermatocysts, which enter the second meiotic division resulting sperm bundle that containing mature sperms. (C), (D), and (E) represent the effects of RNAi on testis development in silkworms at the beginning of the fifth instar, the end of the fifth instar, and 10 days after pupation, respectively. spg, spermatogonium; ps, primary spermatocytes; ss, secondary spermatocytes; sp, cysts of spermatids; ms, mature sperms formed in sperm bundle. Original magnification = ×40.