The Effect of the Suspensor and Gibberellic Acid on Phaseolus Vulgaris Embryo Protein Synthesis

In this thesis the role of the suspensor and gibberellic acid in Phaseolus vulgaris embryo protein content and synthesis was examined. The plant embryo exists in a very specialized environment and this environment must be maintained in tissue culture for continued normal embryonic development. Optimum sucrose concentrations for cult-ure of 0.2 mm and 0.5 mm embryos in Gamborg B5 medium were determined to be 12^ and 6^ respectively. Protein content and synthesis of various culture combinations of these embryos and their suspensors were examined by polyacrylamide electrophoresis. Two-tenths millimeter embryos required an attached suspensor for maximum protein content. Virtually all protein synthesis was dependent upon an attached suspensor. Maximum protein quantity and synthesis in 0.5 mm embryos were observed when the embryo was cultured attached to the suspensor. Protein levels decreased when it was cultured detached from or without _7 the suspensor. Gibberellic acid of 10 M elicited the same protein 35 diversity and greater S -methionine incorporation than the attached suspensor in 0.2 mm embryos. Five-tenths millimeter embryos did not appear to be differentially responsive to various gibberellins concentrations. All of the Gl storage protein subunits and the 32 and 3^ kD G2 storage protein subunits were observed in 0.2 mm embryos. The 0.5 mm embryos in gibberellin had all of the Gl and G2 storage protein subunits.