Component of the origin recognition complex (ORC) that binds origins of replication. DNA-binding is ATP-dependent. The specific DNA sequences that define origins of replication have not been identified yet. ORC is required to assemble the pre- replication complex necessary to initiate DNA replication. Binds histone H3 and H4 trimethylation marks H3K9me3; H3K20me3 and H4K27me3. Stabilizes LRWD1; by protecting it from ubiquitin- mediated proteasomal degradation. Also stabilizes ORC3. {ECO:0000269|PubMed:22427655; ECO:0000269|PubMed:22935713}.