Studies on the haemolymph proteins of the blowfly Phormia regina—I. Changes in ontogenetic patterns

Abstract

Detailed analyses of the haemolymph during development of blowfly Phormia regina have demonstrated a 12-fold increase in haemolymph volume during the 2nd to 5th day of larval life. Within the same period the total concentration of proteins increases about 24-fold, and reaches a maximum value of about 20 per cent (w/v) shortly before pupation. During metamorphosis both haemolymph volume and haemolymph protein concentration fall distinctly, the most rapid decline occurring during the time of transformation from larva to white pupa and at adult emergence. In the newly emerged flies the total protein concentration amounts to 3·5 per cent (w/v) which is only about one-sixth of that in the mature larva. Acrylamide gel electrophoresis indicates the presence of at least 19 protein bands in haemolymph. Characteristic changes in the ontogenetic patterns have been observed during development, including the appearance of new protein fractions and the disappearance of others in both pupal and adult stages. Furthermore, the distinct difference in the electrophoretic patterns between haemolymph and moulting fluid is indicative of the different origin of the respective protein components.