Respiration of larval salivary glands of Drosophila in relation to the activity of specific genome loci

Abstract

Oxygen consumption of intact larval salivary glands of Drosophila hydei was measured after the addition of intermediates of the citric acid cycle or amino acids to the incubation medium. The effect of these substances on respiration of glands previously submitted to anaerobiosis in vivo was compared with that of glands of control larvae. Only isocitrate and tyrosine stimulated respiration of anaerobically treated glands to a much higher extent than glands of control larvae. This stimulatory effect was abolished when RNA or protein synthesis was inhibited. It is suggested that some of the specific puffs occurring as a consequence of anaerobiosis reflect gene activity required for an increase in utilization of isocitrate and tyrosine for respiration under conditions of stress.