Analysis for Protein Glycosylation of Pattern Recognition Receptors in Plants.

Recognition of molecules typical of microbes or aberrant cellular states, termed microbe- or danger-associated molecular patterns (MAMPs/DAMPs), respectively, provides an important step in plant and animal innate immunity. In plants, pattern recognition receptors (PRRs) identified to date are limited to membrane-associated proteins, of which the majority has an extracellular leucine-rich repeat (LRR) or lysine-motif (LysM) domain. These PRRs undergo quality control (QC) in the Endoplasmic Reticulum (ER) that is dependent on Asn (N)-linked glycosylation (Glc3Man9GlcNAc2 conjugation) of their extracellular domain. In Arabidopsis, genetic studies have revealed that a subset of these PRRs require an intact N-glycosylation pathway in the ER for their biogenesis and function. Here, we describe methods for immunoblot-based detection of protein glycosylation states in plants.