Die effek van sikliese adenosien-3':5'-monofosfaat op hemoglobien-biosintese

Abstract

Although cAMP may be involved in the regulation of protein biosynthesis in certain eukaryotic cells no decisive relationship between hormonal action, cAMP and the regulation of translation could be found in the literature. Since the evidence of an effect of cAMP on the translation of mRNA was not unequivocally established, the object of this study was to investigate the effect of cAMP on the synthesis of globin in rabbit reticulocyte in situ and in vitro systems. A stimulation of polypeptide synthesis, i.e. globin biosynthesis, by cAMP could be shown in both systems. In case of the in vitro system the optimal cAMP concentration varied between 4 and 24 mM, whereas the stimulatory effect amounted between 30 and 40C/% . This investigation was fu rther extended to determine the effects of dB cAMP, aminophyline and 5' -AMP on polypeptide synthesis. With regard to the mechanism through which cAMP induce the observed stimulation of protein biosynthesis, an inverse relationship between the presence of an energy regeneration system and ATP and the stimulatory effect of cAMP was found. It was further shown that cAMP stimulates all the translation phases. Possible explanations of the observed results are given.