Figure 3.

Laser Microdissection and LPC to Identify Specific RNAs in Phloem Cells of Potato Stems.

Microdissection was performed on paraffin-imbedded transverse sections of potato stems of wild-type plants (S. tuberosum ssp andigena) using the PALM Microlaser system (Plant Sciences Institute, Iowa State University). For microdissection, focused laser light was used to excise selected cells from regions of the xylem, phloem, or epidermis (X, P, and E in [A], respectively). After microdissection, the sample cells were directly catapulted into an appropriate collection device. RNA was extracted from these cells and used as a template for RT-PCR using gene-specific primers for each RNA sample (B). NT is nitrate transporter (specific for root cells). G2 is the G2-like transcription factor (specific for phloem cells). Identity of PCR products was confirmed by sequencing isolated bands. Data shown are from SD-grown plants. Identical results were obtained when using material from LD-grown plants.