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Abstract Botryllus schlosseri, is a model marine invertebrate for studying immunity, regeneration, and stress‐induced evolution. Conditions for validating its predicted proteome were optimized using nanoElute® 2 deep‐coverage LCMS, revealing up to 4930 protein groups and 20,984 unique peptides per sample. Spectral libraries were generated and filtered to remove interferences, low‐quality transitions, and only retain proteins with >3 unique peptides. The resulting DIA assay library enabled label‐free quantitation of 3426 protein groups represented by 22,593 unique peptides. Quantitative comparisons of single systems from a laboratory‐raised with two field‐collected populations revealed (1) a more unique proteome in the laboratory‐raised population, and (2) proteins with high/low individual variabilities in each population. DNA repair/replication, ion transport, and intracellular signaling processes were distinct in laboratory‐cultured colonies. Spliceosome and Wnt signaling proteins were the least variable (highly functionally constrained) in all populations. In conclusion, we present the first colonial tunicate's deep quantitative proteome analysis, identifying functional protein clusters associated with laboratory conditions, different habitats, and strong versus relaxed abundance constraints. These results empower research onB. schlosseriwith proteomics resources and enable quantitative molecular phenotyping of changes associated with transfer from in situ to ex situ and from in vivo to in vitro culture conditions.
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Deep quantitative proteomics of North American Pacific coast star tunicate
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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- Award ID(s):
- 2127516
- PAR ID:
- 10608748
- Publisher / Repository:
- Panorama Public
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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