Arabidopsis 2010
Identification of New Plastid Division Genes in Arabidopsis and Comprehensive Analysis of Their Functions
Funded by the National Science Foundation

PI: Katherine W. Osteryoung, Michigan State UniversityPlastid division in plants is orchestrated by a complex macromolecular apparatus, the components of which are mostly unknown. We will investigate the functions of a set of predicted and genetically defined Arabidopsis gene products that may participate in plastid division. The proteins to be investigated derive from three sources:

1) predicted proteins having sequence or structural homology to known plastid division, bacterial cell division, mitochondrial fission or fusion, or microtubule-based motor proteins. Gao et al. 2006 in press
2) genes defined by the Arabidopsis arc (accumulation and replication of chloroplasts) mutants.
3) genes encoding proteins with homology to cyanobacterial cell division proteins, to be identified by transposon mutagenesis in Synechococcus PCC 7942. Miyagishima et al. 2005

Functional studies will include examination of knockout lines by microscopy for abnormalities in chloroplast number, size, shape, and FtsZ localization pattern, biochemical assays of protein targeting and topology, and analysis of in vivo localization using GFP fusion proteins. The results are expected to lead to hypotheses regarding the macromolecular organization and biochemical activity of the chloroplast division complex. The research will be relevant to scientists interested in a variety of biological problems, including organelle fission and dynamics, macromolecular organization, organelle evolution, and plant development.

Candidate Genes