Chromatins were fragmentated by sonication and immunoprecipitated with an anti-FLAG M2 antibody or antibodies against protein-of-interest. Immunoprecipitated DNA fragments were purified by QIAGEN's PCR purification Kit. Ten ng of co-immunoprecipitated DNA fragments, exept for Of-S-M and O-Sf-M, were subjected to preparation of Illumina’s sequencing library using NEBNext ChIP-seq Library Prep Reagent (New England Biolabs), according manifacturer's instruction. After adapter ligation, DNA fragments were amplified by PCR with Illumina primers and library fragments of ~250 bp (insert plus adaptor and PCR primer sequences) were band isolated by Caliper XT(Perkinelmer). For Of-S-M and O-Sf-M, Illumina’s sequencing libraries were generated by Ovation SP Iltralow Library System (NuGEN). The purified DNA was captured on an Illumina flow cell for cluster generation.