Genome editing enables reverse genetics of multicellular development in the choanoflagellate Salpingoeca rosetta
Abstract
In a previous study, we established a forward genetic screen to identify genes required for multicellular development in the choanoflagellate, Salpingoeca rosetta (Levin et al., 2014). Yet, the paucity of reverse genetic tools for choanoflagellates has hampered direct tests of gene function and impeded the establishment of choanoflagellates as a model for reconstructing the origin of their closest living relatives, the animals. Here we establish CRISPR/Cas9-mediated genome editing in S. rosetta by engineering a selectable marker to enrich for edited cells. We then use genome editing to disrupt the coding sequence of a S. rosetta C-type lectin gene, rosetteless, and thereby demonstrate its necessity for multicellular rosette development. This work advances S. rosetta as a model system in which to investigate how genes identified from genetic screens and genomic surveys function in choanoflagellates and evolved as critical regulators of animal biology.
Data availability
All data generated are included in the manuscript. Additionally, we have posted a protocol at protocols.io: https://dx.doi.org/10.17504/protocols.io.89fhz3n
Article and author information
Author details
Funding
Gordon and Betty Moore Foundation
- David S Booth
- Nicole King
Howard Hughes Medical Institute
- Nicole King
Jane Coffin Childs Memorial Fund for Medical Research
- David S Booth
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Alejandro Sánchez Alvarado, Stowers Institute for Medical Research, United States
Version history
- Received: February 20, 2020
- Accepted: June 3, 2020
- Accepted Manuscript published: June 4, 2020 (version 1)
- Accepted Manuscript updated: June 9, 2020 (version 2)
- Version of Record published: June 24, 2020 (version 3)
Copyright
© 2020, Booth & King
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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