Comparative proteomic analysis of Bombyx mori hemolymph and fat body after calorie restriction

Calorie restriction (CR) is known to extend life span from yeast to mammals. To gain an insight into the effects of CR on growth and development of the silkworm Bombyx mori at protein level, we employed comparative proteomic approach to investigate proteomic differences of hemolymph and fat body of the silkworm larvae subjected to CR. Thirty-nine differentially expressed proteins were identified by MALDI TOF/TOF MS. Among them, 19 were from the hemolymph and 20 from the fat body. The hemolymph of the CR group contained two down-regulated and 17 up-regulated proteins, whereas the fat body contained 15 down-regulated and five up-regulated ones. These proteins belonged to those functioning in immune system, in signal transduction and apoptosis, in regulation of growth and development, and in energy metabolism. Our results suggest that CR can alter the expression of proteins related to the above four aspects, implying that these proteins may regulate life span of the silkworm through CR.