Submitted to: Journal of Nematology
Publication Type: Abstract Only
Publication Acceptance Date: June 13, 2003
Publication Date: September 1, 2003
Citation: Kovaleva, E.S., Masler, E.P., Sardanelli, S.S., Chitwood, D.J. 2003. Heat shock proteins 70 in heterodera glycines. J. Nematol. 35(3): 348. 2003.
Heat shock proteins 70 (Hsp70) are a ubiquitous and highly conserved group of molecular chaperones that bind nascent and denatured proteins, through an ATP-dependent mechanism, preventing aggregation and improper folding. Some members of this family are expressed at increased levels in response to heat shock. The other, constitutive, members are not heat-inducible and may vary during development. The copious functions of Hsp70 are especially important for endoparasitic nematodes, such as Heterodera glycines, that are exposed to a variety of environmental challenges during their life cycle, including temperature extremes and dietary restriction. Using Western blots we detected several Hsp70 proteins in homogenates of H. glycines, as well as Caenorhabditis elegans, used for comparison. The Hsp70 antiserum, known to react with both vertebrate and invertebrate HSP70s, revealed at least two distinct proteins in H. glycines, which were membrane-associated. In contrast, at least three proteins were detected on the C. elegans blots, one of which was soluble. To investigate the multi-gene family of H. glycines Hsp70 proteins further, two Hsp70 genes were isolated and characterized. The deduced proteins have molecular weights of 71 and 73kDa, and share high homology (80-88 percent amino acid identity) to Hsp70's from a number of nematodes and other invertebrates. In addition, the 73kDa H. glycines Hsp70 is highly homologous to the glucose regulated protein types of Hsp70. Experiments are being conducted to determine the effect of heat shock and diet on members of the H. glycines Hsp70 protein family.