Pluto Bioinformatics

GSE62040: Rb1+/+ versus Rb1S/S RNA Seq

Bulk RNA sequencing

Upon G1-S transition, cyclin-dependent kinases (CDKs) phosphorylate the retinoblastoma tumor suppressor protein (pRB) to release E2F transcription factors, which activate transcriptional programs, required for S-phase entry. Beyond the G1-S transition, pRB activity remains poorly understood. Our lab has discovered that hyperphosphorylated pRB (ppRB), found beyond G1, retains exclusive binding to E2F1 through an alternate E2F1-specific binding site at the pRB c-terminus. We have developed a gene-targeted mouse model that is defective for the E2F1-specific interaction. We are exploring the function of this complex through genome-wide expression profiling. Overall, this work suggests an alternate pRB-E2F1 complex persists beyond the G1-S transition to establish regions of constitutive heterochromatin. SOURCE: Fred Dick (fdick@uwo.ca) - Western University