AN ALPHA-CRYSTALLIN PROTEIN COGNATE IN GERM-CELLS OF THE MOTH, PLODIA-INTERPUNCTELLA

Previously we had reported the production of an antiserum to an antige n found primarily in germ cells of the Indianmeal moth, Plodia interpu nctella (Zimowska et al., 1991), The antigen, molecular weight 25 000 kDa, and a related protein, molecular weight 21 000 kDa, co-purified w ith the follicular epithelium yolk protein, Antisera to the two protei ns were raised, and they both reacted with the same four small polypep tides, which had molecular weights of 20 000, 21 000, 25 000 and 28 00 0 kDa, that were present in the eggs throughout embryogenesis. A 30 am ino acid sequence of an internal fragment of the 25 000 kDa molecular weight polypeptide showed sequence similarity with the alpha-crystalli n A chain polypeptides from the lenses of vertebrate eyes and, to a le sser extent, with small heat shock proteins, Based on the sequence sim ilarity with the a-crystallins, we suggest that this family of polypep tides from the germ cells of this moth be considered as cognates of th e alpha-crystallins, and the 25 000 molecular weight polypeptide descr ibed here be given the designation ac25, Using immune-gold labeling wi th antiserum to ac25, the alpha-crystallins were shown to be distribut ed throughout the cytoplasm and nucleoplasm of the oocyte and nurse ce lls, but not present within yolk spheres or other organelles of the oo cyte or nurse cells, Immunofluorescent staining of males showed antige nic material in the sperm bundles within the testes, Oenocytes of the pupal and adult stages also contained cross-reactive material.