Function
Regulates the timing of initiation of DNA replication (PubMed:29746464, PubMed:30277458, PubMed:26022086). Functions in copy number control by promoting the underreplication of DNA, which is found in many late replicating euchromatic regions of salivary gland polytene chromosomes (PubMed:30277458). Promotes underreplication by localizing to active DNA replication forks in a partially SuUR-dependent manner, and inhibiting replication fork progression (PubMed:30277458). Might also work as an adapter to recruit Pp1-87B to multiple sites on the chromosome and may function with Pp1-87B to mediate underreplication (PubMed:26022086, PubMed:29746464, PubMed:30277458). Plays an essential role in embryonic development, in the transition from larvae to pupae and, probably, in proliferating tissues later on (PubMed:26022086, PubMed:29746464). In embryos, during mid-blastula transition, binds to and selectively delays the replication of large blocks of repetitive DNA satellite sequences during S phase in response to the activity of Cdk1; maternal Rif1 is specifically required for the normal extension of S phase 14 (PubMed:29746464). Unlike mammalian orthologs, does not appear to play a role in DNA damage repair (PubMed:22712556, PubMed:26022086).
Sequence
MDVDFGAQAGQSYRTVQLSAKEVLAAGRRQHYCNMIDLLASSCKSSGLIATSFTDDELVEFWLGDILPLMFDADRKIQDCAVAALAEALVALDVSVIHSAKCWPQIRSEFVDKYTIIIGEMRDAKNSNWHKIWTLLVQIMDEDLLRGCVYINKFLALVELGFRNPDNGVRSEAFLCWRVLIKIFAAYDELTSAKRLRLLLIPLRTSQSRSSHVSGIKLRVWWYLLSCLDHELPKSFDSAVEHFLAFMLGGGPRNLATGLAHNYQTARELALPCLVALWGVESSEPLQRLMRELRLETLVQPSPLMSVEVFQQHWKPLLAAAVSGLKLLTENDATEAEQLLLQLLVRNLCLAMFRLAVAPFNVACCSEIEKILQAEDNSGGRVVRALFNTIAADNLVMERVSGSDHLDVLEAYLKLVLKSKTEVPAAILQRSIACIFAVDRIEANNQNEFRMLGSFAELLMQANDEEDFEGFAFKLQVWRQVSQALSNYLRNNALEYRVAHNASLLDTWLLWPLQTLAAFAGRRASNSFDASFCDQWRQLVNAGQNAPGRKKFLTDLKATLTDLLKSKDEPLFAELFDAYVTSLIKFGLCKEAPLYKDVFGLLQTIFEQPSSQKTLEACLNTLRNLVVELRQNELMVVFDSLKPTLSSGIQCWNKMKCEGGFLEEWKRGIQEKFRKLPMKTMANQLKELFKADDLFVIIPSVWSLNPEKLTDRQKERFAEKSDIPALYNDMSQSQDSASIKPWTPKKVVIAKSKQGELALTGKDDNGEVIDITASEESEKEPVRVDVVTPIRKKPGRKSQAQKELEAAARAASLAEEPPKRQTRTRAAQKETEQVAQPQPAFEPQLRSPKKLPPSPVVQSTAAAVKQAKVAKPTPVVVIAQSEDLFPEVAAEPEPQPEPVKKPDPVPETTQLTPPDVPLEAVPSTQLPGSSGDPAASAGAVAAGEMSPKKSGTRIYNLSSPPDRKQTNNSSSPTLRPKPTGHLTGRGAQLINMIRNKKLDAASGSPYACMSTSRLVHQVTPARAQDRAEQVSTPTSELNELTGTDHTSTPIQAPPSKDLLVFSKRLPSPSASPSVSILKRKLRCESLDDVTLDSPALKRKRVSFHDPPVSVTKEYLRDAEETRSSLKPKRCLLMDKVAQTTEMRQALRRRGRLDSIIEIERFASEQTARTATTDKSLDKSTGEAPEEDAFTSLKWNDTGNAHNISISEEPVKAMEVESELETAGQDLAIMDPEAALDLAVAQLPLESVLQRYFDKSPLKSAGMLAKFLSAQMTANEKLKTNVLETLSENHSKDFLDHAVRENLSSVVCDRLNPTSVLEYVCAKSKISASCRNGLLAQVPEILKSGPRSDSERLAFVQQLMVQCSPGDDLLLDLIDLLMRTRRERNNSTSTHISKGVVSAVGSPDNVAETAADSSSNL