. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. ALLATUM INFLUENCE ON PROTEIN METABOLISM 447 >600- - ALLATECTOMIZED -O SHAM OPERATED. HOURS AFTER INJECTION FIGURE 3. Rate of incorporation of tritium-labelled glycine, leucine, and histidine into the midgut tissue of allatectomized and sham-allatectomized females of P. americana roaches (5 ). Points are averages of two experiments. that the difference is significant at 9 hours and 12 hours after injection of the radioactive amino acids. DISCUSSION We have shown that allatectomy during an ovarian cycle in P. ame
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. ALLATUM INFLUENCE ON PROTEIN METABOLISM 447 >600- - ALLATECTOMIZED -O SHAM OPERATED. HOURS AFTER INJECTION FIGURE 3. Rate of incorporation of tritium-labelled glycine, leucine, and histidine into the midgut tissue of allatectomized and sham-allatectomized females of P. americana roaches (5 ). Points are averages of two experiments. that the difference is significant at 9 hours and 12 hours after injection of the radioactive amino acids. DISCUSSION We have shown that allatectomy during an ovarian cycle in P. americana females results in a lower level of total body RNA and protein, and that total body uric acid fails to increase as it does in control females. Furthermore, there is marked decrease in total incorporation of radioactive amino acids into protein of ovarian and fat body tissues following allatectomy. The decreased body levels of protein and decreased synthesis of tissue proteins may be a consequence of a decrease in RNA synthesis. Clever and Karlson (1960) observed in larvae of Chironomus tentans that injected ecdysone induces chromosomal puffs, which could be demonstrated by autoradiography to be sites of RNA synthesis. It is possible that the allatum hormone functions in a similar manner to control RNA synthesis. Uric acid in insects is formed principally from protein catabolism and the lack of an increase in urate level in allatectomized females, in the absence of any detectable increase in urate excretion, may be interpreted as the consequence of a decreased protein catabolism. Bodenstein (1953) observed a loss of urates from the fat body when corpora cardiaca were removed, but little or no effect was found upon removal of only the corpora allata. Our results support his observations that allatectomy has no influence on stored urates. The most conclusive evidence for participation of the corpora allata in protein synthesis comes from the isotope incorporation experiment
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
