Distinct roles of Arabidopsis ORC1 proteins in DNA replication and heterochromatic H3K27me1 deposition.

ABSTRACT: Most cellular proteins involved in genome replication are conserved in all eukaryotic lineages including yeast, plants and animals. However, the mechanisms controlling their availability during the cell cycle are less well defined. Here we show that the Arabidopsis genome encodes for two ORC1 proteins highly similar in amino acid sequence and that have partially overlapping expression domains but with distinct functions. The ancestral ORC1b gene, present before the partial duplication of the Arabidopsis genome, has retained the canonical function in DNA replication. ORC1b is expressed in both proliferating and endoreplicating cells, accumulates during G1 and is rapidly degraded upon S-phase entry through the ubiquitin-proteasome pathway. In contrast, the duplicated ORC1a gene has acquired

SUBMITTER: Vergara Z 

PROVIDER: S-EPMC9992703 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature