Abstract
Two types of ftsZ genes (MpftsZ1 and MpftsZ2) were isolated from the liverwort Marchantia polymorpha using degenerate RT-PCR. Northern analysis confirmed that both genes are active. Transformation of a sense MpftsZ2 overexpression construct into M. polymorpha produced a large chloroplast phenotype in one transgenic plant. The epidermal cells of wild-type plants contained a mean ± SD of 38.2 ± 21.4 chloroplasts, whereas the chloroplast number was 7.4 ± 4.4 in the transgenic plant. Southern analysis showed that the CaMV 35S promoter-MpftsZ2 construct was inserted in at least three positions. Northern analysis suggested that the high accumulation of MpftsZ2 mRNA blocked plastid division. Determination of the chlorophyll content and chlorophyll fluorescence parameters suggested that the macrochloroplasts function like chloroplasts in wild-type plants under normal light conditions. However, the transgenic plant grew more slowly than did wild-type plants.
