Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: BITING AND STINGING PESTS: ECOLOGY AND BIOLOGICALLY-BASED CONTROL

Location: Biological Control of Pests Research Unit

Title: Identification and transcription profiling of Trypsin in Aedes taeniorhynchus (Diptera: Culicidae): Developmental regulation, blood feeding, and Permethrin exposure

Authors
item Zhao, Liming
item Chen, Jian
item Becnel, James
item Kline, Daniel
item Clark, Gary
item Linthicum, Kenneth

Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 28, 2011
Publication Date: May 16, 2011
Citation: Zhao, L., Chen, J., Becnel, J.J., Kline, D.L., Clark, G.G., Linthicum, K. 2011. Identification and transcription profiling of Trypsin in Aedes taeniorhynchus (Diptera: Culicidae): Developmental regulation, blood feeding, and Permethrin exposure. Journal of Medical Entomology. 48(3):546-553.

Interpretive Summary: We have cloned and sequenced cDNA of trypsin gene from Aedes (Ochlerotatus) taeniorhynchus (Weidemann) adult. Trypsin, found in the digestive system of invertebrates and vertebrates, is a serine protease that hydrolyses proteins. Trypsin is one of the three principal digestive proteinases, the other two are pepsin and chymotrypsin. In the digestive process, trypsin acts with the other proteinases to break down dietary protein molecules to their component peptides and amino acids in both larvae and adults. In female mosquitoes, trypsin proteins are expressed following a blood meal. Transcription of an early trypsin gene, controlled by juvenile hormone, is part of the normal post-emergence maturation of the midgut in these females. We used a quantitative real-time polymerase chain reaction (qPCR) to examine AetTryp mRNA expression levels in different developmental stages of Ae. taeniorhynchus. AetTryp was expressed at low levels in egg, larval, and pupal stages but was differentially expressed in adult Ae. taeniorhynchus, with highest levels found in 5 day old female adults when compared to teneral adults. In addition, AetTryp mRNA expression differed between sexes, with expression levels much lower in male adults. The mRNA transcription levels of AetTryp mRNA expression in response to a blood meal and permethrin treatment in female adults Ae. taeniorhynchus was also determined.

Technical Abstract: The cDNA of a trypsin gene from Aedes (Ochlerotatus) taeniorhynchus (Weidemann) was cloned and sequenced. The full-length mRNA sequence (874 bp) for trypsin from Ae. taeniorhynchus (AetTryp) was obtained which encodes an open reading frame of 717 bp (i.e., 239 aa). To detect whether AetTryp is developmentally regulated, a quantitative real-time polymerase chain reaction (qPCR) was used to examine AetTryp mRNA expression levels in different developmental stages of Ae. taeniorhynchus. AetTryp was expressed at low levels in egg, larval, and pupal stages but was differentially expressed in adult Ae. taeniorhynchus, with highest levels found in 5d-old female adults when compared to teneral adults. In addition, AetTryp mRNA expression differed between sexes, with expression levels much lower in males. However, in both males and females there was a significant increase in AetTryp transcription levels as age increased and peaked in 5d-old adults. The mRNA transcription levels of AetTryp mRNA expression in response to a blood meal and permethrin treatment in female Ae. taeniorhynchus was determined.

Last Modified: 7/22/2014
Footer Content Back to Top of Page