Title of Paper:A Sperm-Plasma beta-N-Acetyl-D-Hexosaminidase Interacting with a Chitinolytic beta-N-Acetyl-D-Hexosaminidase in Insect Molting Fluid

Hits:

Date of Publication:2013-08-12

Journal:PLOS ONE

Included Journals:SCIE、PubMed

Volume:8

Issue:8

Page Number:e71738

ISSN No.:1932-6203

Abstract:Insects require molting fluids to shed the old cuticle during molting. beta-N-acetyl-D-hexosaminidase, known as Hex1, together with various chitinases, is responsible for degrading the chitin component of the old cuticle. This study showed that another beta-N-acetyl-D-hexosaminidase, termed Of Hex3, interacted with Hex1 and functioned in the molting fluid, although the homolog of Of Hex3 was known as a sperm-plasma enzyme functioning in egg-sperm recognition. Of Hex3 is an enzyme cloned from the insect Asian corn borer, Ostrinia furnacalis, which is one of the most destructive pests of maize. The enzymatic activity analysis indicated that Of Hex3 was able to degrade chitooligosaccharides, but at a lower rate than that of Of Hex1. Because Of Hex3 did not have substrate inhibition, we deduced that the presence of Of Hex3 might help Of Hex1 relieve substrate inhibition during chitin degradation during molting. The expression patterns of Of Hex3 during O. furnacalis development were studied by real-time PCR as well as western blot. The results showed that both gene transcription and protein translation levels of Of Hex3 were up-regulated during larval-larval molting. The tissue-specific expression pattern analysis indicated that Of Hex3 was mostly localized in the fat body and testis. All these data further supported that Hex3 was involved in molting as well as in fertilization. This study may help to understand the complexity of cuticle degradation during insect molting, and may provide a possible target for pest control.