Predicted glycosyltransferases promote development and prevent spurious cell clumping in the choanoflagellate S. rosetta
- Howard Hughes Medical Institute, University of California, Berkeley, United States
Abstract
In a previous study we established forward genetics in the choanoflagellate Salpingoeca rosetta and found that a C-type lectin gene is required for rosette development (Levin et al. 2014). Here we report on critical improvements to genetic screens in S. rosetta while also investigating the genetic basis for rosette defect mutants in which single cells fail to develop into orderly rosettes but instead aggregate promiscuously into amorphous clumps of cells. Two of the mutants, Jumble and Couscous, mapped to lesions in genes encoding two different predicted glycosyltransferases and displayed aberrant glycosylation patterns in the basal extracellular matrix (ECM). In animals, glycosyltransferases sculpt the polysaccharide-rich ECM, regulate integrin and cadherin activity, and, when disrupted, contribute to tumorigenesis. The finding that predicted glycosyltransferases promote proper rosette development and prevent cell aggregation in S. rosetta suggests a pre-metazoan role for glycosyltransferases in regulating development and preventing abnormal tumor-like multicellularity.
Data availability
Data have been deposited to the NCBI Sequence Read Archive under the project number PRJNA490902.
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Jumble mutant of Salpingoeca rosettaNCBI BioSample, SAMN10061445.
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Couscous mutant of Salpingoeca rosettaNCBI BioSample, SAMN10061446.
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Seafoam mutant gDNA sequencingNCBI BioSample, SAMN10501893.
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Soapsuds mutant gDNA sequencingNCBI BioSample, SAMN10501894.
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Jumble mutant gDNA sequencingNCBI Sequence Read Archive, SRR7866767.
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Couscous mutant gDNA sequencingNCBI Sequence Read Archive, SRR7866768.
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Rosetteless x Mapping Strain cross gDNA sequencingNCBI Sequence Read Archive, SRR7866769.
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Jumble x Mapping Strain cross gDNA sequencingNCBI Sequence Read Archive, SRR7866770.
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Couscous x Mapping Strain cross gDNA sequencingNCBI Sequence Read Archive, SRR7866771.
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Soapsuds mutant gDNA sequencingNCBI Sequence Read Archive, SRR8263909.
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Seafoam mutant gDNA sequencingNCBI Sequence Read Archive, SRR8263910.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Laura A Wetzel
- Tera C Levin
- Ryan E Hulett
- Daniel Chan
- Grant A King
- Reef Aldayafleh
- David S Booth
- Monika Abedin Sigg
- Nicole King
Jane Coffin Childs Memorial Fund for Medical Research (Simons Fellow)
- David S Booth
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Wetzel et al.
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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Predicted glycosyltransferases promote development and prevent spurious cell clumping in the choanoflagellate S. rosetta
eLife 7:e41482.
https://doi.org/10.7554/eLife.41482
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