DISSECTING DNA REPLICATION THROUGH CHEMICAL GENETICS AND QUANTITATIVE PHOSPHOPROTEOMICS; CONNECTING CDC7 KINASE FUNCTION WITH SUBSTRATES AND MECHANISMS
Dr Mathew Jones is a senior postdoctoral fellow at Memorial Sloan Kettering Cancer Center (MSKCC) in the laboratory of Dr Prasad Jallepalli. Dr Jones completed his postgraduate training in the Signal Transduction laboratory at the QIMR Berghofer Medical Research Institute and received his PhD from the University of Queensland in 2009.
Dr Jones performed postdoctoral training at New York University in the laboratory of Dr Tony Huang, studying the role of the Fanconi Anemia pathway in DNA replication and repair. In 2011, Dr Jones moved to MSKCC where he has developed chemical genetic techniques to study DNA replication and repair in human cells.
SYNOPSIS
Small molecule inhibitors targeting the DNA replication kinase Cdc7 have shown encouraging results in preclinical tumor models; however, their broad specificity and weak penetrance preclude their ability to functionally assess the role of Cdc7.
To address this issue, we used adeno-associated virus (AAV) vectors to delete and replace the catalytic subunit of Cdc7 (CDC7L1) in human somatic cells with a version that could be rapidly and specifically inhibited by bulky purine analogs. Using this approach, we have discovered that Cdc7 is required to preserve the stability of stalled replication forks.
To understand the mechanisms underlying this regulation, we used quantitative phosphoproteomics to identify novel Cdc7 substrates at stalled replication forks. In addition to many known sites on MCM2-7, we identified novel Cdc7-dependent phosphorylation on the ring-shaped cohesin complex and the BRCA1-A complex. Genetic dissection of these substrates revealed both contribute to Cdc7’s role in fork protection.
Dr Matthew Jones
Memorial Sloan Kettering Cancer Center (MSKCC)
New York
