CRAF dimerization with ARAF regulates KRAS driven tumors
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Orbitrap Eclipse, Orbitrap Fusion Lumos
ORGANISM(S): Homo Sapiens (ncbitaxon:9606)
SUBMITTER: 
Shiva Malek
PROVIDER: MSV000088285 | MassIVE | Fri Oct 29 16:16:00 BST 2021
REPOSITORIES: MassIVE
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Project description:KSR1 is a scaffolding protein for the RAS-RAF-MEK-ERK pathway, which is one of the most frequently altered pathways in human cancers. Previous results have shown that KSR1 has a critical role in mutant RAS mediated transformation. Here, we examined the role of KSR1 in mutant BRAF transformation. We used CRISPR/Cas9 to knock out KSR1 in a BRAFV600E transformed melanoma cell line. KSR1 loss produced a complex phenotype characterized by impaired proliferation, cell cycle defects, decreased transformation, decreased invasive migration, increased cellular senescence, and increased apoptosis. To decipher this phenotype, we used a combination of proteomic ERK substrate profiling, global protein expression profiling, and biochemical validation assays. The results suggest that KSR1 directs ERK to phosphorylate substrates that have a critical role in ensuring cell survival. The results further indicate that KSR1 loss induces the activation of p38 Mitogen- Activated Protein Kinase (MAPK) and subsequent cell cycle aberrations and senescence. In summary, KSR1 function plays a key role in oncogenic BRAF transformation.
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