Global Cell Surface Conformational Shift Mediated by a
            <i>Candida albicans</i>
            Adhesin

Rauceo, Jason M.; Gaur, Nand K.; Lee, Kyeng Gea; Edwards, John E.; Klotz, Stephen A.; Lipke, Peter N.

doi:10.1128/iai.72.9.4948-4955.2004

Cited by 64 publications

(112 citation statements)

References 30 publications

Supporting

Mentioning

106

Contrasting

Order By: Relevance

“…Because killed cells cannot increase surface expression of adhesins in response to the mechanical stimulus, we infer that the increase in active Als5p molecules and their clustering must be due to rearrangement of molecules already present on the cell surface. These results show that the force-induced clustering of Als5p is independent of cellular metabolic activity, consistent with the notion that Als5p-mediated aggregation does not involve metabolic activity (16).…”

Section: Resultssupporting

confidence: 76%

“…These kinetics suggest that, following adhesion to ligands, Als5p may undergo conformational changes that mediate cellular aggregation. Consistent with this, Rauceo et al (16) found that, following adhesion of one region of the cell to fibronectin-coated beads, the entire surface of the cell became competent to mediate cell-cell aggregation. This led the authors to suggest a model for Als5p-mediated aggregation in which an adhesion-triggered change in the conformation of Als5p propagates around the cell surface, forming ordered adhesion domains.…”

supporting

confidence: 55%

“…These observations show that the formation of Als5p clusters in a 500 × 500-nm target area takes about 30 min (i.e., between 25 and 37.5 min). After the domains are formed, they propagate at a speed of ∼20 nm·min −1 (500 nm in 25 min), suggesting that propagation across the entire cell is reached within ∼6 h. Because activation kinetics from adhesion assays show faster activation (10-30 min) (16,27), we believe that the speed of propagation in vivo is due to activation at several points on the cell surface through interaction with beads or other cells. These results lead us to conclude that domain formation and propagation are two slow, time-dependent processes.…”

Section: Resultsmentioning

confidence: 99%

“…Als5p and other yeast adhesion proteins have conserved amyloid-forming sequences, and self-propagating amyloid formation is important for formation of robust cellular aggregates (13,14,16). The V326N single-site mutation in the amyloid-forming region of Als5p abrogates amyloid formation (13).…”

Section: Resultsmentioning

confidence: 99%

“…Aggregation assays were carried out as previously described (16), with cells activated during a 60-min adhesion assay to BSAcoated beads under shear in the presence of 100 nM thioflavin T (Sigma). Cells were observed at 5-min intervals beginning 90 min after aggregation to mimic the preobservation interval under AFM conditions.…”

Section: Methodsmentioning

confidence: 99%

See 4 more Smart Citations

Force-induced formation and propagation of adhesion nanodomains in living fungal cells

Alsteens

Garcia

Lipke

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

182

273

View full text Add to dashboard Cite

Understanding how cell adhesion proteins form adhesion domains is a key challenge in cell biology. Here, we use single-molecule atomic force microscopy (AFM) to demonstrate the force-induced formation and propagation of adhesion nanodomains in living fungal cells, focusing on the covalently anchored cell-wall protein Als5p from Candida albicans. We show that pulling on single adhesins with AFM tips terminated with specific antibodies triggers the formation of adhesion domains of 100-500 nm and that the forceinduced nanodomains propagate over the entire cell surface. Control experiments (with cells lacking Als5p, single-site mutation in the protein, bare tips, and tips modified with irrelevant antibodies) demonstrate that Als5p nanodomains result from protein redistribution triggered by force-induced conformational changes in the initially probed proteins, rather than from nonspecific cell-wall perturbations. Als5p remodeling is independent of cellular metabolic activity because heat-killed cells show the same behavior as live cells. Using AFM and fluorescence microscopy, we also find that nanodomains are formed within ∼30 min and migrate at a speed of ∼20 nm·min −1 , indicating that domain formation and propagation are slow, time-dependent processes. These results demonstrate that mechanical stimuli can trigger adhesion nanodomains in fungal cells and suggest that the force-induced clustering of adhesins may be a mechanism for activating cell adhesion.single-molecule techniques | microbial adhesion | glycoproteins | fungi C ell adhesion is a ubiquitous feature of living cells and plays essential roles in a variety of cellular processes, including neuronal interactions, cellular communication, inflammation, and microbial infection (1-5). A growing body of evidence indicates that, in mammalian cells, the early stage of adhesion involves the formation of adhesion domains (i.e., focal adhesion complexes) composed of aggregated proteins (6, 7). A remarkable trait of adhesion domains is their ability to grow and strengthen under force (8-10). Whether such force-dependent behavior also occurs with microbial adhesins is unknown.Adhesins in the Candida albicans Als gene family bind the pathogen to host tissues and initiate biofilm formation (11,12). Als proteins are covalently attached to the cell wall and consist of an N-terminal Ig-like region, which initiates cell adhesion, followed by a threonine-rich region with an amyloid-forming sequence (T), a tandem repeat (TR) region that participates in cellcell aggregation, and a stalk region projecting the molecule away from the cell surface (Fig. 1A) (13-15). Previous studies in C. albicans and in a Saccharomyces cerevisiae surface display model showed that Als5p-mediated adhesion involves a rapid cellto-ligand adhesion step, followed by slower cell-to-cell aggregation mediated by the T and TR regions (13, 15). These kinetics suggest that, following adhesion to ligands, Als5p may undergo conformational changes that mediate cellular aggregation. Consistent with this, Rauceo ...

show abstract

Section: Resultssupporting

confidence: 76%

supporting

confidence: 55%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Force-induced formation and propagation of adhesion nanodomains in living fungal cells

Alsteens

Garcia

Lipke

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

182

273

View full text Add to dashboard Cite

show abstract

Current awareness on yeast

2005

Yeast

View full text Add to dashboard Cite

In order to keep subscribers up‐to‐date with the latest developments in their field, this current awareness service is provided by John Wiley & Sons and contains newly‐published material on yeasts. Each bibliography is divided into 10 sections. 1 Books, Reviews & Symposia; 2 General; 3 Biochemistry; 4 Biotechnology; 5 Cell Biology; 6 Gene Expression; 7 Genetics; 8 Physiology; 9 Medical Mycology; 10 Recombinant DNA Technology. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. (4 weeks journals ‐ search completed 8th. Dec. 2004)

show abstract

Absence of repellents in Ustilago maydis induces genes encoding small secreted proteins

Teertstra¹,

Krijgsheld²,

Wösten³

2011

Antonie van Leeuwenhoek

View full text Add to dashboard Cite

The rep1 gene of the maize pathogen Ustilago maydis encodes a pre-pro-protein that is processed in the secretory pathway into 11 peptides. These so-called repellents form amphipathic amyloid fibrils at the surface of aerial hyphae. A SG200 strain in which the rep1 gene is inactivated (∆rep1 strain) is affected in aerial hyphae formation. We here assessed changes in global gene expression as a consequence of the inactivation of the rep1 gene. Microarray analysis revealed that only 31 genes in the ∆rep1 SG200 strain had a fold change in expression of ≥2. Twenty-two of these genes were up-regulated and half of them encode small secreted proteins (SSPs) with unknown functions. Seven of the SSP genes and two other genes that are over-expressed in the ∆rep1 SG200 strain encode proteins that can be classified as secreted cysteine-rich proteins (SCRPs). Interestingly, most of the SCRPs are predicted to form amyloids. The SCRP gene um00792 showed the highest up-regulation in the ∆rep1 strain. Using GFP as a reporter, it was shown that this gene is over-expressed in the layer of hyphae at the medium-air interface. Taken together, it is concluded that inactivation of rep1 hardly affects the expression profile of U. maydis, despite the fact that the mutant strain has a strong reduced ability to form aerial hyphae.

show abstract

Global Cell Surface Conformational Shift Mediated by a Candida albicans Adhesin

Cited by 64 publications

References 30 publications

Force-induced formation and propagation of adhesion nanodomains in living fungal cells

Force-induced formation and propagation of adhesion nanodomains in living fungal cells

Current awareness on yeast

Absence of repellents in Ustilago maydis induces genes encoding small secreted proteins

Contact Info

Product

Resources

About