In vivo imaging of the S-locus receptor kinase in arabidopsis

Inhibition of ‘self’ pollen in the self-incompatibility response of the Brassicaceae is initiated by interaction of the plasma-membrane–spanning SRK receptor with its cognate pollen-coat–localized SCR ligand. Rea and Nasrallah visualize the Arabidopsis lyrata-derived SRKb variant in stigma epidermal cells, the site of the SRK–SCR interaction, using confocal microscopy in transgenic A. thaliana and find that construction of several transgenes permits differential visualization of various combinations of the three protein species produced from the SRK gene. The results demonstrate that full-length SRKb is localized primarily at the plasma membrane and, importantly, that the secreted eSRKb product is not required for self-incompatibility.