Tissue-specific organelle DNA degradation mediated by DPD1 exonuclease.

Lay Yin Tang, Wataru Sakamoto

Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama, Japan.

Plant signaling & behavior 2011 Sep

filter terms:

Organelle DNA in plastids and mitochondria is present in multiple copies and undergoes degradation developmentally. For example, organelle DNA that is detectable cytologically using DNA-fluorescent dye disappears during pollen development. Nevertheless, nucleases involved in this degradation process remain unknown. Our recent study identified the organelle nuclease, DPD1, which has Mg2+ -dependent exonuclease activity in vitro. The discovery of DPD1 emerged from Arabidopsis mutant screening and concomitant isolation of dpd1 mutants that retain organelle DNA in mature pollen. DPD1 is conserved only in angiosperms: not in other photosynthetic organisms. Despite these findings, the physiological significance of organelle DNA degradation during pollen development remains unclear because dpd1 exhibits no apparent defects in pollen viability or in the maternal inheritance of organelle DNA. We discuss a possible role of organelle DNA degradation mediated by DPD1, based on a DPD1 expression profile studied using in silico analyses.

Citation

Lay Yin Tang, Wataru Sakamoto. Tissue-specific organelle DNA degradation mediated by DPD1 exonuclease. Plant signaling & behavior. 2011 Sep;6(9):1391-3