Overexpression of the Arabidopsis thalianaMinE1 bacterial division inhibitor homologue gene alters chloroplast size and morphology in transgenic Arabidopsis and tobacco plants

Higher-plant chloroplast division requires some of the same genes that are involved in prokaryotic cell division. These include the FtsZ and MinD proteins. Other genes that might be involved in higher-plant chloroplast division have yet to be characterized. The Arabidopsis thaliana (L.) Heynh. MinE (AtMinE1) gene was identified in the genomic database, isolated by reverse transcription-polymerase chain reaction and constitutively expressed in tobacco (Nicotiana tabacum L.) and Arabidopsis plants in both the sense and antisense orientation. Confocal and electron-microscopic analysis of the sense-overexpressing AtMinE1 transgenic tobacco and Arabidopsis plants revealed that the chloroplasts were abnormal in size and shape compared to wild-type Arabidopsis and tobacco chloroplasts. Our results, based on the overexpression of the AtMinE1 gene in tobacco and Arabidopsis, confirm that the AtMinE1 gene is involved in plant chloroplast division.