Host: The Japanese Society of Plant Physiologists
Pages 0226
To examine the replication and inheritance of plastid DNA, we have established efficient plastid transformation systems for the liverwort Marchantia polymorpha. Progenies of the cross between wild type and spectinomycin-resistant plastid transformant showed antibiotic resistance depending on the maternal genotype of plastid DNA. This indicates that the plastid DNA in liverwort is maternally inherited. To investigate the replication mode of the plastid DNA, two-dimensional agarose gel electrophoresis was performed using vigorously growing liverwort suspension-cultured cells. Replication intermediates that proceeded in the short-single-copy (SSC) region and stopped near the boundary region between the SSC and the inverted repeat regions were detected. This result suggests that the liverwort plastid DNA has a region that stops a replication fork until the other fork in the opposite direction reaches the region and also prevents a replication fork from colliding with the transcriptional machinery for the rRNA operon.
