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The first proteomics analysis of a colonial tunicate (Botryllus schlosseri) was carried out to support development of a DIA assay library and quantitative proteomics for this species. Deep proteome coverage (up to 4930 protein groups and 20,984 unique peptides in a single sample) was achieved, which enabled construction of a QC filtered DIA assay library consisting of nearly 4000 proteins that are represented by at least 3 unique peptides, each by at least 4 transitions. This library was used to compare protein abundances of two field populations and one lab-reared B. schlosseri population. Relative protein abundance data indicate that lab-rearing leads to greater proteome changes than those observed between distantly located field populations in Southern California and Northern Washington. STRING analysis revealed functions that are enriched in specific populations and proteins that are least and most variable within a given population.
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Starvation-Induced Changes to the Midgut Proteome and Neuropeptides in Manduca sexta
Starvation is a complex physiological state that induces changes in protein expression to ensure survival. The insect midgut is sensitive to changes in dietary content as it is at the forefront of communicating information about incoming nutrients to the body via hormones. Therefore, a DIA proteomics approach was used to examine starvation physiology and, specifically, the role of midgut neuropeptide hormones in a representative lepidopteran, Manduca sexta. Proteomes were generated from midguts of M. sexta fourth-instar caterpillars, starved for 24 h and 48 h, and compared to fed controls. A total of 3047 proteins were identified, and 854 of these were significantly different in abundance. KEGG analysis revealed that metabolism pathways were less abundant in starved caterpillars, but oxidative phosphorylation proteins were more abundant. In addition, six neuropeptides or related signaling cascade proteins were detected. Particularly, neuropeptide F1 (NPF1) was significantly higher in abundance in starved larvae. A change in juvenile hormone-degrading enzymes was also detected during starvation. Overall, our results provide an exploration of the midgut response to starvation in M. sexta and validate DIA proteomics as a useful tool for quantifying insect midgut neuropeptide hormones.
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- Award ID(s):
- 2236698
- PAR ID:
- 10508162
- Publisher / Repository:
- Insects
- Date Published:
- Journal Name:
- Insects
- Volume:
- 15
- Issue:
- 5
- ISSN:
- 2075-4450
- Page Range / eLocation ID:
- 325
- Subject(s) / Keyword(s):
- feeding endocrine peptidome tobacco hornworm lepidoptera
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/insects15050325
