Component of the DNA topoisomerase VI involved in chromatin organization and progression of endoreduplication cycles. Relaxes both positive and negative superturns and exhibits a strong decatenase activity. Involved in cell-elongation processes. ATP-dependent breakage, passage and rejoining of double-stranded DNA. Homodimer. Heterotetramer of two TOP6A and two TOP6B subunits. Interacts with BIN4 and RHL1. Highly expressed in leaves, stems, flowers and seedlings. Plants are defective in cell elongation and show a severe dwarf phenotype. Belongs to the TOP6A family.