Iris F J, Sin F Y
Department of Zoology, University of Canterbury, Christchurch, New Zealand.
Gen Comp Endocrinol. 1988 Jul;71(1):105-15. doi: 10.1016/0016-6480(88)90301-2.
We studied the in vitro effects of JH III and ecdysterone on RNA synthesis and secretory activities of the left colleterial gland (LCG) in mature females of Periplaneta americana during the reproductive cycle. We found that RNA synthesis is a cyclic and highly dynamic process. The major increases in poly(A)- RNA synthesis occurred 8 hr before the peak leucine incorporation into colleterial polypeptides, whereas high poly(A)+ RNA synthesis coincided with high leucine incorporation. Depending on the stage of the cycle JH III exhibited stimulatory or inhibitory effects, or caused no change in RNA synthesis. JH III stimulated RNA synthesis in glands from stages in the reproductive cycle with high endogenous RNA synthesis. The pattern of protein synthesis was not affected by JH III. Ecdysterone lowered RNA synthesis in the LCG and induced secretory activity in LCGs isolated at stages far removed from ovulation. JH III reduced the inhibitory effect of ecdysterone on RNA synthesis and inhibited the ecdysterone-induced secretory activity. The presence of ovarioles isolated at 62 hr of the reproductive cycle (onset of in vivo LCG secretory activity) in the incubation medium inhibited RNA synthesis in 32 hr LCG but induced secretory activity. We suggest that changes in synthetic and secretory activities are coordinated with ovulation and ootheca formation through the interactions between JH III and ovarioles, and ecdysterone may also play a role.
我们研究了保幼激素III（JH III）和蜕皮激素对美洲大蠊成熟雌虫生殖周期中左输卵管腺（LCG）RNA合成及分泌活性的体外影响。我们发现RNA合成是一个周期性且高度动态的过程。聚腺苷酸（poly(A)-）RNA合成的主要增加发生在亮氨酸掺入输卵管多肽达到峰值前8小时，而高聚腺苷酸（poly(A)+）RNA合成与高亮氨酸掺入同时出现。根据生殖周期的阶段，JH III表现出刺激、抑制作用或对RNA合成无影响。JH III刺激了生殖周期中内源性RNA合成较高阶段腺体的RNA合成。蛋白质合成模式不受JH III影响。蜕皮激素降低了LCG中的RNA合成，并在远离排卵阶段分离的LCG中诱导了分泌活性。JH III降低了蜕皮激素对RNA合成的抑制作用，并抑制了蜕皮激素诱导的分泌活性。在孵育培养基中加入生殖周期62小时（体内LCG分泌活性开始时）分离的卵巢小管，抑制了32小时LCG中的RNA合成，但诱导了分泌活性。我们认为，合成和分泌活性的变化通过JH III与卵巢小管之间的相互作用与排卵和卵鞘形成相协调，蜕皮激素可能也发挥了作用。
