Tissue-specific transcription of proteases and nucleases across the accessory salivary gland, principal salivary gland and gut of Nezara viridula. (December 2018)

• Record Type: Journal Article
• Authors: Liu, Sijun; Lomate, Purushottam R.; Bonning, Bryony C.
• Is Part Of: Insect biochemistry and molecular biology. Volume 103(2018)
• Page Start: 36
• Page End: 45
• Publication Date: 2018-12
• Subjects: Stink bugs -- Nezara viridula -- Transcriptome -- Proteases -- Nucleases -- Digestion; Insect biochemistry -- Periodicals; Insects -- Physiology -- Periodicals; Insects -- Molecular aspects -- Periodicals; Biochemistry -- Periodicals; Insectes -- Biochimie -- Périodiques; Insectes -- Composition -- Périodiques; Insectes -- Physiologie -- Périodiques; Insectes -- Aspect moléculaire -- Périodiques; Biochimie -- Périodiques; Biochemistry; Insect biochemistry; Insects -- Molecular aspects; Insects -- Physiology; Periodicals; 572.8157
• DOI: 10.1016/j.ibmb.2018.10.003
• Languages: English
• ISSNs: 0965-1748

Abstract

Abstract: The phytophagous stink bug, Nezara viridula (L.) infests multiple plant species and impacts agricultural production worldwide. We analyzed the transcriptomes of N. viridula accessory salivary gland (ASG), principal salivary gland (PSG) and gut, with a focus on putative digestive proteases and nucleases that present a primary obstacle for the stability of protein- or nucleic acid-based stink bug control approaches. We performed high throughput Illumina sequencing followed by de novo transcriptome assemblies. We identified the sequences of 141 unique proteases and 134 nucleases from the N. viridula transcriptomes. Analysis of relative transcript abundance in conjunction with previously reported proteome data (Lomate and Bonning, 2016) supports high levels of serine protease expression in the salivary glands and high cysteine protease expression in the gut. Specifically, trypsin and chymotrypsin transcripts were abundant in the PSG, and cathepsin L-like cysteine protease transcripts were abundant in the gut. Nuclease transcript levels were generally lower than those of the proteases, the exception being abundant transcripts of ribonuclease-C20 in the PSG. The abundance of chymotrypsin, trypsin, and some carboxypeptidase transcripts suggests a significant role for the PSG in production of digestive enzymes. This result is at odds with the premise that the ASG produces watery saliva, which is high in enzymatic activity, while the PSG produces only sheath saliva. We have generated a comprehensive transcriptome sequence dataset from the digestive organs of N. viridula, identified major protease and nuclease genes and confirmed expression of the most abundant enzymes thereby providing greater insight into the digestive physiology of N. viridula . Graphical abstract: Highlights: The stink bug, Nezara viridula digests proteins and nucleotides via extra-oral digestion and in the gut. 141 proteases and 134 nucleases identified from accessory salivary gland, principal salivary gland and gut transcriptomes. Trypsin, chymotrypsin transcripts abundant in the PSG, cathepsin L-like cysteine protease transcripts abundant in the gut. Sequences of the most abundant enzymes were confirmed by reference to proteomic data.