Abstract
In the green alga Pediastrum boryanum NIES-301, plastocyanin functions as a redox carrier between the cytochrome b6/f complex and P700 in the electron transport chain of oxygenic photosynthesis. Plastocyanin is encoded by a single nuclear gene (Pcy1) and the expression is dependent on the presence of copper in the medium. We cloned and characterized the Pcy1 gene from P. boryanum genomic DNA. Comparison of the genomic sequence with the cDNA sequence revealed that the coding region is interrupted by a single intron, similar to the Pcy1 gene of the Chlamydomonas reinhardtii. The 5' upstream and coding regions show highest sequence homology to the Pcy1 gene of Scenedesmus obliquus. The 3' downstream region reveals no significant similarity to sequences of other genes.
