Figure 7.

Binding of ORC1 but not HP1 is dependent on Sir2 at the TAREs. (A) Chromatin immunoprecipitation using antisera against PfSir2 from wild-type and Sir2 knock out parasite line shows that Sir2 binds to TAREs and var gene promoters in wild-type but not in the Sir2 knock out parasite line. (B) ChIP experiments using antisera against PfORC1 as described above shows that PfORC1 binds to TAREs and var gene promoters in the wild-type 3D7 parasites but the binding is severely affected in Sir2 knock out parasites. (C) ChIP experiments using antisera against apicoplast targeted PfSSB followed by PCR amplification using primer sets from apicoplast IRA (internal repeat A) shows the binding of SSB to the IRA region in both 3D7 and Sir2 knock out line suggesting that the ChIP experiments are equally efficient in both the cases. (D) ChIP experiments using antisera against PfHP1 as described in (A) and (B) above shows that PfHP1 binds to TAREs and var gene promoters in the wild-type 3D7 parasites as well as in Sir2 knock out parasites.