Abstract
Peroxisomes undergo dramatic changes in size, shape, number and position within the cell, but the division process of peroxisomes has not been characterized. We screened a number of Arabidopsis mutants with aberrant peroxisome morphology (apm mutants). In one of these mutants, apm1, the peroxisomes are long and reduced in number, apparently as a result of inhibition of division. We showed that APM1 encodes ADL2A (Arabidopsis dynamin-like protein 2A), and that mutations in APM1/ADL2A also caused aberrant morphology of mitochondria. The transient expression analysis showed that ADL2A is associated with peroxisomes. These findings indicate that the same dynamin molecule is involved in peroxisomal and mitochondrial division in higher plants. We also report that the growth of Arabidopsis, which requires the cooperation of various organelles including peroxisomes and mitochondria, is repressed in apm1, indicating that the changes of morphology of peroxisomes and mitochondria reduce the efficiency of metabolism in these organelles.
