Cytoplasmic/nuclear plant lectins:: a new story

Plant lectins comprise a widespread group of carbohydrate-binding proteins that show a marked heterogeneity with respect to their molecular structure, sugar-binding specificity and temporal and spatial regulation. Until recently, the role of most lectins was associated with their binding to foreign glycans in either recognition and/or defence-related phenomena. Over the past few years, evidence has accumulated to support the idea that when plants are stimulated by specific biotic or abiotic stimuli they respond through the expression of cytoplasmic and/or nuclear plant lectins. The location and the regulation of the expression of these lectins indicate that lectins; are involved in specific endogenous protein-carbohydrate interactions. These novel findings led to the challenging idea that lectins might be involved in cellular regulation and signalling.