Blood protein synthesis in pupae of the silkmoth, Hyalophora cecropia

The blood proteins of pupae of Hyalophora cecropia were studied by acrylamide gel electrophoresis. Analyses of fractions separated on Sephadex G-75 columns revealed that a series of low molecular weight proteins previously reported to be absent in diapausing pupae are a normal component of diapausing pupal blood. Incorporation of isotopically labelled leucine into blood protein bands of injured pupae, perfused pupae, and perfused isolated pupal abdomens (lacking a midgut) revealed that each of these three preparations could synthesize all of the low molecular weight protein bands, with maximal incorporation in the perfused whole pupae.