The role of DDK and Treslin-MTBP in coordinating replication licensing and pre-initiation complex formation

Ilaria Volpi, Peter J. Gillespie, Gaganmeet Singh Chadha, Julian Blow

Research output: Contribution to journalArticlepeer-review

14 Citations (Scopus)


Treslin/Ticrr is required for the initiation of DNA replication and binds to MTBP (Mdm2 Binding Protein). Here we show that in Xenopus egg extract, MTBP forms an elongated tetramer with Treslin containing two molecules of each protein. Immunodepletion and add-back experiments show that Treslin-MTBP is rate-limiting for replication initiation. It is recruited onto chromatin before S phase starts and recruitment continues during S phase. We show that DDK activity both increases and strengthens the interaction of Treslin-MTBP with licensed chromatin. We also show that DDK activity cooperates with CDK activity to drive the interaction of Treslin-MTBP with TopBP1 which is a regulated crucial step in pre-Initiation Complex formation. These results suggest how DDK works together with CDKs to regulate Treslin-MTBP and plays a crucial in selecting which origins will undergo initiation.
Original languageEnglish
Article number210121
JournalOpen Biology
Issue number10
Early online date27 Oct 2021
Publication statusPublished - Oct 2021


  • DNA replication
  • MTBP
  • Sld7
  • Treslin
  • Ticrr
  • Sld3
  • TopBP1
  • Dbp11
  • Xenopus
  • CDK
  • Cdc7
  • DDK
  • PP1
  • simurosertib
  • cell cycle

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