Abstract

This thesis has three main objectives, the main focus being a study of the TBC2 translational activation protein and its association with the psbC mRNA 5'-untranslated region. The translated TBC2 cDNA sequence had two paralogous protein sequences located within possible nucleotide open reading frames designated TBC2A and TBC2B , and all contained sequences resembling chloroplast transit peptides. TBC2Ap and TBC2Bp harbored the novel PPPEW repeat originally found in TBC2p. The second part of this thesis encompasses the theorized existence of a novel thylakoid biogenesis compartment in the C. reinhardtii chloroplast. Pulse-labeling experiments revealed equivalent synthesis of envelope-like membrane proteins in light versus dark growth conditions, providing no evidence supporting the transport theory through a novel thylakoid biogenesis compartment. The final topic of this thesis addresses the theory of chloroplast genome localization, paralleled to prior findings that the PEND protein in peas binds plastid nucleoids to the envelope membrane. A restriction digest determined that DNA found associated with low density membranes was only nuclear