Microtubule Associated Proteins in Plants and the Processes They Manage Research Progresses on Genes Involved in Regulation of Plant Organ Size SLC/AGO1 Coordinates Cell Division and Expansion in Arabidopsis Overexpression of OsKTN80a, a katanin P80 ortholog, caused the repressed cell elongation and stalled cell division mediated by microtubule apparatus defects in primary root in Oryza sativa