Transcription control of the 32 kDa-QB protein of photosystem II in differentiated bundle sheath and mesophyll chloroplasts of maize

AbstractBundle sheath chloroplasts of maize, a C4 plant, lack a functional herbicide-binding site and the 32 kDa-QB thylakoid protein of photosystem II. Measurements of the amounts of QB-protein mRNA in bundle sheath and mesophyll chloroplasts by hybridization to a cloned psbA probe, and analysis of in vitro translation products of bundle sheath and mesophyll RNA show that during differentiation of maize leaf cells to bundle sheath and mesophyll, the expression of the chloroplast gene, psbA, which encodes the 32 kDa-QB protein, is controlled at the transcriptional level