Meeting Abstract

P1.75  Sunday, Jan. 4  Characterization of a Photoperiodically Regulated Protein from a Woodroach. WASSMER, Gary; Bloomsburg University of Pennsylvania gwassmer@bloomu.edu

The woodroach, Parcoblatta pennsylvanica, is one of the few species of roach that is able to overwinter at subfreezing temperatures. As winter approaches, the growth rate of the insects slows and molting ceases. Laboratory and field studies have shown that this change in post-embryonic growth rate is photoperiodically regulated, not a direct result of lower temperature. Other studies have shown that, in parallel with the changes in growth rate, the concentration of hemolymph proteins is photoperiodically controlled. Hemolymph concentration increases in response to shortening daylength. In addition, we see that the types of protein change with photoperiod. In particular, one hemolymph protein which we have called DASP (Development Associated Storage Protein) is abundant during long daylength but unnoticeable when daylength shortens. We believe this protein to be one in the class of storage proteins in insect hemolymph. This conclusion is based on several observations that are consistent with the characteristics of other reported storage proteins: 1) it is very abundant in the hemolymph, 2) the molecular weight is close to other reported values for storage protein, 3) the holoprotein is a hexamer, 4) it is not another suspect apolipophorin, and 5) it is not detectable in the adult male. The results presented here show further characterization of DASP, including partial amino acid sequence and suspected homology with other proteins isolated from insects.