This proposal requests funds for a fluorescence- activated cell sorter (FACS) system. A FACS uses laser technology to examine fluorescently tagged intracellular and cell surface proteins and DNA content of live or fixed individual cells and to then sort cells according to their fluorescence and/or DNA content. Research that will be supported by the instrument includes: the action of the molecular chaperonin calreticulin; lentivirus-host interactions; mycoplasm host cell receptors; viral transmission mechanisms; dessication resistance in plants; protein folding by the ER; and hormonal regulation of protein phosphorylation in the ovary.