DNA replication occurs only once per cell cycle, and numerous pathways prevent re-replication. Here it is shown that mutations in ARABIDOPSIS TRITHORAX-RELATED PROTEIN5 (ATXR5) and ATXR6 — which encode histone methyltransferases — lead to re-replication of specific genomic locations, notably those corresponding to transposons and other repetitive and silenced elements. ATXR5 and ATXR6 are proposed to be components of a pathway that prevents over-replication of heterochromatin in Arabidopsis.
- Yannick Jacob
- Hume Stroud
- Steven E. Jacobsen
