The consensus N_glyco‐X‐S/T motif and a previously unknown N_glyco‐N‐linked glycosylation are necessary for growth and pathogenicity of Phytophthora

Abstract

Asparagine (Asn, N)-linked glycosylation within N glyco -X-S/T; X ≠ P motif is a ubiquitously distributed post-translational modification that participates in diverse cellular processes. In this work, N-glycosylation inhibitor was shown to prevent Phytophthora sojae growth, suggesting that N-glycosylation is necessary for oomycete development. We conducted a glycoproteomic analysis of P. sojae to identify and map N-glycosylated proteins and to quantify differentially expressed glycoproteins associated with mycelia, asexual cyst, and sexual oospore developmental stages. A total of 355 N-glycosylated proteins was found, containing 496 glycosites, potentially involved in glycan degradation, carbon metabolism, glycolysis, or other metabolic pathways. Through PNGase F deglycosylation assays and site-directed mutagenesis of a GPI transamidase protein (GPI16) upregulated in cysts and a heat shock protein 70 (HSP70) upregulated in oospores, we demonstrated that both proteins were N-glycosylated and that the N glyco -N motif is a target site for asparagineoligosaccharide linkage. Glycosite mutations of Asn 94 N glyco -X-S/T in the GPI16 led to impaired cyst germination and pathogenicity, while mutation of the previously unknown Asn 270 N glyco -N motif in HSP70 led to decreased oospore production. In addition to providing a map of the oomycete N-glycoproteome, this work confirms that P. sojae has evolved multiple N-glycosylation motifs essential for growth.

Characterization of PcSTT3B as a Key Oligosaccharyltransferase Subunit Involved in N-glycosylation and Its Role in Development and Pathogenicity of Phytophthora capsici

“…N-glycosylation within the N-X-Ser/Thr (X = Pro) motif is a post-translational modification that is ubiquitous and participates in various cellular processes. In P. sojae, the N-glycosylation inhibitor at 2.5 µg/mL of TM prevents the growth of P. sojae and cyst germination [34]. In Magnaporthe oryzae, 5 µg/mL of TM significantly inhibited mycelial growth, mycelial cell length, conidiophore formation, and invasive hyphal growth in host cells [26].…”

A Phytophthora receptor-like kinase regulates oospore development and can activate pattern-triggered plant immunity

“…In P. infestans , silencing of a gene that encodes loricrin-like protein blocked oospore wall formation 32 . As for P. sojae , YPK1 (a serine/threonine protein kinase-encoding gene) 33 , YKT6 (a soluble N -ethylmaleimide-sensitive factor attachment protein receptors) 34 , GK5 (a G-protein-coupled receptor with a phosphatidylinositol phosphate kinase domain) 35 , IMPA1 (a conserved importin α ) 36 , and N -glycosylation in HSP70 37 also play important roles in oospore production while the mechanisms of regulating oospore development remain largely elusive. Here, we showed that PsRLK6 plays an indispensable role in oospore production and morphological development.…”

N-glycosylation of envelope glycoprotein gI is crucial for the duck plague virus proliferation and virulence

“…This process involves the assembly of monosaccharides into polysaccharides, mediated by lipids and a variety of enzymes within the endoplasmic reticulum and Golgi apparatus. Proteins recognize the polysaccharides through a speci c consensus sequence N-X-T/S, where the glycosyltransferases catalyze the attachment of the polysaccharides to the asparagine residue at speci c sequence [19][20][21][22]. Abnormal glycosylation can lead to a reduction in virulence of both animal and plant pathogens [23].…”