Distribution of Phytochrome in Subcellular Fractions From Maize Coleoptiles Following Glutaraldehyde Treatment

Abstract

Localization of phytochrome in subcellular fractions of maize cells was determined using glutaraldehyde treatment and biochemical fractionation techniques. Glutaraldehyde treatment enhanced phytochrome pelletability in fractions from red-irradiated but not dark-grown or far red-irradiated maize coleoptiles. The glutaraldehyde-induced pelletability of phytochrome represented a bonded form of phytochrome because it was resistant to washings with concentrated salt and EDTA solutions. A number of the characteristics of glutaraldehyde-induced phytochrome pelletability support the claim that inside the cell, phytochrome becomes associated with its reaction partner(s) upon red irradiation and this association can be stabilized by chemical crosslinkage with glutaraldehyde.