The genetic interaction network of CCW12, a Saccharomyces cerevisiae gene required for cell wall integrity during budding and formation of mating projections

Abstract

BackgroundMannoproteins construct the outer cover of the fungal cell wall. The covalently linked cell wall protein Ccw12p is an abundant mannoprotein. It is considered as crucial structural cell wall component since in baker's yeast the lack of CCW12 results in severe cell wall damage and reduced mating efficiency.ResultsIn order to explore the function of CCW12, we performed a Synthetic Genetic Analysis (SGA) and identified genes that are essential in the absence of CCW12. The resulting interaction network identified 21 genes involved in cell wall integrity, chitin synthesis, cell polarity, vesicular transport and endocytosis. Among those are PFD1, WHI3, SRN2, PAC10, FEN1 and YDR417C, which have not been related to cell wall integrity before. We correlated our results with genetic interaction networks of genes involved in glucan and chitin synthesis. A core of genes essential to maintain cell integrity in response to cell wall stress was identified. In addition, we performed a large-scale transcriptional analysis and compared the transcriptional changes observed in mutant ccw12Δ with transcriptomes from studies investigating responses to constitutive or acute cell wall damage. We identified a set of genes that are highly induced in the majority of the mutants/conditions and are directly related to the cell wall integrity pathway and cell wall compensatory responses. Among those are BCK1, CHS3, EDE1, PFD1, SLT2 and SLA1 that were also identified in the SGA. In contrast, a specific feature of mutant ccw12Δ is the transcriptional repression of genes involved in mating. Physiological experiments substantiate this finding. Further, we demonstrate that Ccw12p is present at the cell periphery and highly concentrated at the presumptive budding site, around the bud, at the septum and at the tip of the mating projection.ConclusionsThe combination of high throughput screenings, phenotypic analyses and localization studies provides new insight into the function of Ccw12p. A compensatory response, culminating in cell wall remodelling and transport/recycling pathways is required to buffer the loss of CCW12. Moreover, the enrichment of Ccw12p in bud, septum and mating projection is consistent with a role of Ccw12p in preserving cell wall integrity at sites of active growth.The microarray data produced in this analysis have been submitted to NCBI GEO database and GSE22649 record was assigned.

Critical role for CaFEN1 and CaFEN12 of Candida albicans in cell wall integrity and biofilm formation

“…1). CFW sensitivity of FEN1 deletant was also reported earlier, after being identified through a screen for genetic interaction with CCW12 , a gene involved in CWI39. Among other deletants, lcb3 Δ/Δ and sur2 Δ/Δ were found to be slightly sensitive to CFW (Fig.…”

A common strategy for initiating the transition from proliferation to quiescence

“…Srl3 is a S uppressor of R ad53 L ethality when over-produced (Ouspenski, et al 1999). Srl3 is induced by DNA damage and other forms of stress (Gasch, et al 2000, Lee, et al 2000, Ragni, et al 2011). It has been shown to bind SBF transiently in DNA damage (Travesa, et al 2013) and mediate the nuclear localization of Cln3 (Yahya, et al 2014).…”

The yeast sphingolipid signaling landscape

“…The tsc10 Δ and elo2 Δ strains were shown to be sensitive to cell wall insults such as calcofluor white (Pagé et al, 2003; Ragni et al, 2011) and SDS (Pagé et al, 2003). In some cases more mechanistic detail has been gleaned, such as increased activity of the MAP kinase Slt2 in elo3 Δ strain indicating that Elo3 is involved in cell wall stress not in cell wall assembly (Ragni et al, 2011).…”

“…The tsc10 Δ and elo2 Δ strains were shown to be sensitive to cell wall insults such as calcofluor white (Pagé et al, 2003; Ragni et al, 2011) and SDS (Pagé et al, 2003). In some cases more mechanistic detail has been gleaned, such as increased activity of the MAP kinase Slt2 in elo3 Δ strain indicating that Elo3 is involved in cell wall stress not in cell wall assembly (Ragni et al, 2011). Specific alterations in cell wall properties have been observed such as altered mannose/glucose ratio in ipt1 Δ, altered levels of beta-1,3-glucans in elo2 Δ (el-Sherbeini and Clemas, 1995), and elo3 Δ (Pagé et al, 2003).…”