Characterization of a desiccation-related protein in lily pollen during development and stress

This work characterizes a lily (Lilium longiflorum Thunb. cv, Snow Queen) a nther (LLA) protein associated with desiccation. Peptide mapping analysis r evealed that the abundant LLA-23 doublet contained similar polypeptides, ha ving an isoelectric point of 6.1. Immunoblots of pollen protein from develo ping anther/pollen confirmed that the LLA-23 protein accumulated only at th e later stage of pollen maturation and that the levels remained steady in m ature and vital pollen. The accumulation of LLA-23 proteins was correlated with desiccation that naturally occurred in pollen. Subcellular fractionati on of pollen proteins revealed that the protein was located in the cytoplas mic fraction. Premature drying of developing pollen confirmed that the conc omitant accumulation of LLA-23 was associated with desiccation. Peptide seq uence analysis demonstrates similarities between the lily LLA-23 and a fami ly of water-deficit/ripening-induced proteins including LP3 of pine, DS2 of potato, and Asr of tomato and pummelo, In addition, the concomitant accumu lation of LLA-23 can be experimentally manipulated by methyl jasmonate (MeJ A) and salicylic acid (SA as well as by mannitol and methyl viologen. The L LA-23 represents a novel member of the water-deficit/ripenine-induced prote ins.