<i>O</i>‐Mannosylation precedes and potentially controls the <i>N</i>‐glycosylation of a yeast cell wall glycoprotein

Ecker, Margit; Mrša, Vladimir; Hagen, Ilja; Deutzmann, Rainer; Strahl, Sabine; Tanner, Widmar

doi:10.1038/sj.embor.embor864

Cited by 77 publications

(85 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In accordance with this, it has been described that some S. cerevisisae proteins, such as Kre9p, Cts1p, Bar1p, Pir2p, and Aga2p, are exclusively O-mannosylated by the heterodimer PMT1/PMT2 (Gentzsch and Tanner, 1997), while proteins such as Kex2p, Gas1p, Axl2p, and Fus1p are modified only by PMT4 (Gentzsch and Tanner, 1997;Proszynski et al, 2004). By contrast, other proteins, such as members of the WSC family, Mid2p and Ccw5p/Pir4p, are O-mannosylated by both complexes (Ecker et al, 2003;Lommel et al, 2004). In order to determine other PMT targets, in silico studies based on the general characteristics of O-mannosylated proteins have been initiated (Hutzler et al, 2007).…”

Section: Introductionmentioning

confidence: 75%

TheO-Mannosyltransferase PMT4 Is Essential for Normal Appressorium Formation and Penetration inUstilago maydis

2009

View full text Add to dashboard Cite

In Saccharomyces cerevisiae, the PMT, KRE2/MNT1, and MNN1 mannosyltransferase protein families catalyze the steps of the O-mannosylation pathway, sequentially adding mannoses to target proteins. We have identified members of all three families and analyzed their roles in pathogenesis of the maize smut fungus Ustilago maydis. Furthermore, we have shown that PMT4, one of the three PMT family members in U. maydis, is essential for tumor formation in Zea mays. Significantly, PMT4 seems to be required only for pathogenesis and is dispensable for other aspects of the U. maydis life cycle. We subsequently show that the deletion of pmt4 results in a strong reduction in the frequency of appressorium formation, with the few appressoria that do form lacking the capacity to penetrate the plant cuticle. Our findings suggest that the O-mannosylation pathway plays a key role in the posttranslational modification of proteins involved in the pathogenic development of U. maydis. The fact that PMT homologs are not found in plants may open new avenues for the development of fungal control strategies. Moreover, the discovery of a highly specific requirement for a single O-mannosyltransferase should aid in the identification of the proteins directly involved in fungal plant penetration, thus leading to a better understanding of plant-fungi interactions.

show abstract

Section: Introductionmentioning

confidence: 75%

TheO-Mannosyltransferase PMT4 Is Essential for Normal Appressorium Formation and Penetration inUstilago maydis

2009

View full text Add to dashboard Cite

show abstract

“…In contrast, Kex2p, Gas1p, Axl2p, and Fus1p are Omannosylated by Pmt4p (15,17). A third group of proteins including the WSC-family members, Mid2p and Ccw5p/Pir4p, is glycosylated by both complexes; however, Pmt1p/Pmt2p and Pmt4p mannosylate different domains of the protein (16,18). In contrast to other types of glycosylation, signals causing O-mannosylation of Ser and Thr residues by PMT family members and determinants of the different substrate specificities among the PMT complexes are unknown.…”

mentioning

confidence: 99%

“…Second, members of the PMT1 subfamily physically interact with members of the PMT2 subfamily, whereas the unique representative of the PMT4 subfamily forms homomeric complexes (14). Third, Pmt1p/Pmt2p and Pmt4p complexes mannosylate different acceptor proteins in vivo (15,16). In S. cerevisiae, a subset of O-mannosylated proteins such as Kre9p, Cts1p, Bar1p, Pir2p, and Aga2p is exclusively mannosylated by Pmt1p/Pmt2p complexes (15).…”

mentioning

confidence: 99%

Membrane association is a determinant for substrate recognition by PMT4 protein O -mannosyltransferases

Hutzler

Schmid

Bernard

et al. 2007

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

Self Cite

View full text Add to dashboard Cite

“…In the yeast Saccharomyces cerevisiae, O-linked oligomannose chains are required for the stability, correct localization, and/or function of proteins (1)(2)(3)(4)(5)(6). Yeast O-mannosylation is initiated in the lumen of the endoplasmic reticulum by a family of protein O-mannosyltransferases, PMT1-PMT6, 1 which catalyze the transfer of Man from dolichylphosphate Man to Ser or Thr residues of secretory proteins (7)(8)(9). The PMT family is classified phylogenetically into the PMT1, PMT2, and PMT4 subfamilies.…”

mentioning

confidence: 99%

The Twisted Abdomen Phenotype of Drosophila POMT1 and POMT2 Mutants Coincides with Their Heterophilic Protein O-Mannosyltransferase Activity

Ichimiya

Manya

Ohmae

et al. 2004

Journal of Biological Chemistry

110

View full text Add to dashboard Cite

Walker-Warburg syndrome, caused by mutations in protein O-mannosyltransferase-1 (POMT1), is an autosomal recessive disorder characterized by severe brain malformation, muscular dystrophy, and structural eye abnormalities. As humans have a second POMT, POMT2, we cloned each Drosophila ortholog of the human POMT genes and carried out RNA interference (RNAi) knockdown to investigate the function of these proteins in vivo. Drosophila POMT2 (dPOMT2) RNAi mutant flies showed a "twisted abdomen phenotype," in which the abdomen is twisted 30 -60°, similar to the dPOMT1 mutant. Moreover, dPOMT2 interacted genetically with dPOMT1, suggesting that the dPOMTs function in collaboration with each other in vivo. We expressed dPOMTs in Sf21 cells and measured POMT activity. dPOMT2 transferred a mannose to the dystroglycan protein only when it was coexpressed with dPOMT1. Likewise, dPOMT1 showed POMT activity only when coexpressed with dPOMT2, and neither dPOMT showed any activity by itself. Each dPOMT RNAi fly totally reduced POMT activity, despite the specific reduction in the level of each dPOMT mRNA. The expression pattern of dPOMT2 mRNA was found to be similar to that of dPOMT1 mRNA using whole mount in situ hybridization. These results demonstrate that the two dPOMTs function as a protein O-mannosyltransferase in association with each other, in vitro and in vivo, to generate and maintain normal muscle development.

show abstract

O‐Mannosylation precedes and potentially controls the N‐glycosylation of a yeast cell wall glycoprotein

Cited by 77 publications

References 39 publications

TheO-Mannosyltransferase PMT4 Is Essential for Normal Appressorium Formation and Penetration inUstilago maydis

TheO-Mannosyltransferase PMT4 Is Essential for Normal Appressorium Formation and Penetration inUstilago maydis

Membrane association is a determinant for substrate recognition by PMT4 protein O -mannosyltransferases

The Twisted Abdomen Phenotype of Drosophila POMT1 and POMT2 Mutants Coincides with Their Heterophilic Protein O-Mannosyltransferase Activity

Contact Info

Product

Resources

About