三眠蚕诱导剂SM-1对家蚕丝蛋白合成调控机理的研究——Ⅱ.SM-1对后部丝腺DNA合成速率和核酸含量的影响

本文探讨三眼蚕诱导剂SM一1对家蚕丝蛋白合成的调控机理.试验结果表明:(1)sM-1处理后,家蚕后部丝腺DNA中~3H-胸腺嘧啶核苷的参入速率明显增快.SM一1诱导三眠蚕在四龄第2天~3H-胸腺嘧啶核苷的参入量最高,比同时的对照高近1倍;五龄第2天SM—1处理区,在五龄第3天~H-胸腺嘧啶核苷的参入速率有所增快.(2)SM-1诱导的三眠蚕,后丝腺DNA和RNA含量的高峰比对照提前4-6天出现,且其末龄(四龄)DNA和RNA含量的增减趋势与对照末龄(五龄)DNV和RNA含量的增减趋势非常相似.(3)五龄前期用SM一1处理家蚕幼虫,对后丝腺DNA和RNA含量增加具有暂时的促进作用.

EFFECT OF TRIMOLTING SILKWORM INDUCER SM-1 ON THE REGULATION MECHANISMS OF THE SILK FIBROIN SYNTHESIS OF SILKWORM——Ⅱ. Effects of SM-1 on the Synthetic Rate of DNA and Nucleic Acid Content in the Posterior Silkglands

The regulation mechanisms of SM-1 on silk fibroin synthesis in silkworm,Bombyx mori, were studied in this paper, the results arc as follows: 1) After silkworms were treated by SM-1, the incorporation rate of 3H- thymidinc into DNA in the posterior silkglands was accelerated markedly. The incorporation rate of 3H- thymidinc into DNA in the posterior silkglands of the trimolting silkworm larvae induced by SM-1 reached its highest point on the second day of the forth instar and was increased by one times compared with CK, while that treated by SM-1 on the second day of the fifth instar was increased slightly on the third day of the fifth instar compared with CK. 2) The peaks of DNA and RNA contents in the posterior silkglands of the trimolting silkworm larvae induced by SM-1 apcarcd 4-6 days carlier than those of control, and the change tendencies of DNA and RNA in the posterior silkglands of the final instar in both treated larvae (4th instar) and controlled ones (5th instar) arc very similar. 3) The DNA and RNA contents in the posterior silkglands were increased temporarily when the silkworm larvae were treated by SM-1 during the fore stage of the fifth instar.