Altered N-glycan composition impacts flagella mediated adhesion in Chlamydomonas reinhardtii
- Institute of Hydrobiology, Chinese Academy of Sciences, China
- University of Münster, Germany
- University of Liverpool, United Kingdom
- Max Planck Institute for Dynamics and Self-Organization, Germany
- Humboldt University of Berlin, Germany
- Max Planck Institute for Dynamics and Self Organization, Germany
Abstract
For the unicellular alga Chlamydomonas reinhardtii, the presence of N-glycosylated proteins on the surface of two flagella is crucial for both cell-cell interaction during mating and flagellar surface adhesion. However, it is not known whether only the presence or also the composition of N-glycans attached to respective proteins is important for these processes. To this end, we tested several C. reinhardtii insertional mutants and a CRISPR/Cas9 knockout mutant of xylosyltransferase 1A, all possessing altered N-glycan compositions. Taking advantage of atomic force microscopy and micropipette force measurements, our data revealed that reduction in N-glycan complexity impedes the adhesion force required for binding the flagella to surfaces. This results in impaired polystyrene bead binding and transport but not gliding of cells on solid surfaces. Notably, assembly, intraflagellar transport and protein import into flagella are not affected by altered N-glycosylation. Thus, we conclude that proper N-glycosylation of flagellar proteins is crucial for adhering C. reinhardtii cells onto surfaces, indicating that N-glycans mediate surface adhesion via direct surface contact.
Data availability
The mass spectrometry proteomics data (Figure 1) have been deposited to the ProteomeXchange Consortium (http://proteomecentral.proteomexchange.org) via the PRIDE partner repository with the dataset identifier PXD018353.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (Hi 737 / 12-1)
- Michael Hippler
National Natural Science Foundation of China (Grant 31671399)
- Kaiyao Huang
Royal Society (UF120411,URF\R\180030,RGF\EA\181061 and RGF\EA\180233)
- Lu-Ning Liu
Biotechnology and Biological Sciences Research Council (BB/R003890/1,BB/M012441/1)
- Lu-Ning Liu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Xu 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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Altered N-glycan composition impacts flagella mediated adhesion in Chlamydomonas reinhardtii
eLife 9:e58805.
https://doi.org/10.7554/eLife.58805
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