METABOLIC SIGNIFICANCE OF THE DIETARY CMP REQUIREMENT IN RELATION TO ARTEMIA MORPHOGENESIS

¹ Laboratoire du Muséum National d'Histoire Naturelle, C.E.R.S. 64200 Biarritz (France)

In Artemia, the effect of actinomycin D, which inhibits RNA synthesis, and the effect of puromycin, which inhibits protein synthesis, depend on the AMP:CMP ratio of the diet. When RNA synthesis is limited by CMP concentrations deficient in relation to AMP, protein synthesis decreases and the abdominal length of Artemia increases. When RNA synthesis is limited by AMP concentrations deficient in relation to CMP, protein synthesis increases and Artemia abdominal segments develop supernumerary gonopodes. Induction of supernumerary gonopodes by a reduced AMP:CMP ratio is suppressed by an albumin deficiency and by puromycin. These results suggest that supernumerary gonopodes are induced by a reduced RNA:protein ratio.