Proteases and nucleases across midgut tissues of Nezara viridula (Hemiptera:Pentatomidae) display distinct activity profiles that are conserved through life stages. (November 2019)

• Record Type: Journal Article
• Authors: Cantón, Pablo Emiliano; Bonning, Bryony C.
• Is Part Of: Journal of insect physiology. Volume 119(2019)
• Publication Date: 2019-11
• Subjects: BApNA Nα-Benzoyl-D, L-arginine 4-nitroanilide hydrochloride -- SAAPFpNA N-Succinyl-Ala-Ala-Pro-Phe p-nitroanilide -- LpNA L-Leucine p-nitroanilide -- pGFLpNA pGlu-Phe-Leu p-nitroanilide -- zRRpNA Z-Arg-Arg p-nitroanilide -- PMSF Phenylmethylsulfonyl fluoride -- TLCK Nα-Tosyl-L-lysine chloromethyl ketone hydrochloride -- TPCK Nα-Tosyl-L-phenylalaninechloromethyl ketone -- EDTA Ethylenedintrilotetraecetic acid -- DMSO dimethyl sulfoxide -- GO Gene ontology -- PCA Principal component analysis; Stink bug -- Digestive protease -- Nuclease -- Midgut -- Transcriptome; Insects -- Physiology -- Periodicals; Insectes -- Physiologie -- Périodiques; Insects -- Physiology; Periodicals; 571.157
• DOI: 10.1016/j.jinsphys.2019.103965
• Languages: English
• ISSNs: 0022-1910

Abstract

Graphical abstract: Highlights: The transcriptome reflects the biochemical profiles of midgut regions M1 to M3. The distinct digestive profiles of M1 to M3 are conserved in adults and nymphs. Serine and cysteine protease inhibitors are produced by multiple tissues. Cytochrome P450s provide additional midgut metabolic flexibility. Abstract: The southern green stink bug, Nezara viridula is a polyphagous pest of commercially important crops during both nymph and adult stages. This insect has recently transitioned from a secondary agricultural pest to one of primary concern. Novel management solutions are needed due to the limited effectiveness of current control strategies. We performed biochemical and transcriptomic analyses to characterize digestive enzymes in the salivary glands and along midgut tissues of N. viridula nymphs and adults fed on sweet corn. The digestive profiles were more distinct between midgut regions (M1 to M3) than between life stages. Aminopeptidase and chymotrypsin activities declined from the M1 (anterior) toward the M3 midgut region. Cysteine protease activity was higher in the M2 and M3 regions than in M1. Differences in sensitivity to chymotrypsin inhibitors between midgut regions suggest that distinct genes or isoforms are expressed in different regions of the gut. In nymphs, DNA and RNA degradation was higher in M1 than in M3. Adult nuclease activity was low across all midgut regions, but high in salivary glands. The differences in protease activities are reflected by transcriptomic data and functional enrichment of GO terms. Together, our results show that different regions of the digestive tract of N. viridula have specific and distinct digestive properties, and increase our understanding of the physiology of this organism.