Laser microdissection of phytoplasma-infected grapevine leaf phloem tissue for gene expression study

Abstract Phytoplasmas have been found confined mainly in leaf phloem sieve elements. In spite of this, few researches have been focused on the infected phloem tissue, whereas the plant response at the infection site could be quite different compared to distal parts and almost completely masked when whole organs are considered. Herein, we provide a protocol for the isolation of leaf phloem from paraffin-embedded samples by Laser Microdissection, followed by RNA purification and RNA amplification to generate cDNA libraries. Our protocol, which has been set up for phytoplasma-infected field-grown grapevine and successfully used for gene expression profiling, can be modified according to different plant species.