The parS(INT1) entry in FlyBase represents a small DNA sequence (typically less than 1kb) containing a cluster of parS sites derived from Burkholderia cenocepacia chromosome c2. The parS(INT1) DNA sequence is specifically bound by parB1, the protein encoded by the parB gene from Burkholderia cenocepacia chromosome c2 (PMID:16452432). parB1 protein binds to parS(INT1) and then spreads along adjacent DNA, due to oligomerization of the parB1 protein. This property can be used to visualize chromosome regions in vivo, by fusing the parB1 protein to a fluorescent protein (PMID:24625580).