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Myc. Location of Myc In the Genome. What is Myc? What Cancers is Myc involved in? What happens to Myc to cause these cancers?. Like Src, Myc was first discovered as v-myc in chickens. This transforming retrovirus caused the formation of foci in chickens.
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Myc Location of Myc In the Genome • What is Myc? • What Cancers is Myc involved in? • What happens to Myc to cause these cancers?
Like Src, Myc was first discovered as v-myc in chickens. • This transforming retrovirus caused the formation of foci in chickens. • It was later found that a non-viral homologue of v-myc was present in mice and humans. • This caused scientists to ask what myc does under normal circumstances.
Myc is a Transcription Factor Myc E-box Genes Controlled by Myc DNA • Involved in gene expression • Myc recognizes a promoter sequence called the E-box which has nucleotide sequence CACGTG. • When bound, myc regulates the function of genes downstream of this promoter region.
Myc Does not act alone Does Myc exert positive or negative control over transcription?
What genes does Myc regulate? + Control Cell Cycle Regulation Apoptosis Myc Max Metabolism CACGTG - Control Cell Adhesion Cellular Differentiation
Cell Cycle Control • Myc exerts its influence at the G1-S transition by regulation of CDK’s and CDKI’s. • Used homologous recombination to create cells without myc. • Myc-null cells have a decreased probability of entering cell cycle.
Under normal circumstances… Cyclin D and E CDK4 and cdc25 Induce Promotion through G1-S Transition. myc max E-box P27 (in the family Of p21) Inhibit
So how exactly does Myc become overexpressed? • 3 mechanisms • Gene Amplification • Osteosarcoma, leukemia • Point Mutations • Burkett’s Lymphoma • Chromosomal Translocations • Burkett’s Lymphoma
Review • Myc is a transcription factor • Myc influences the expression of genes involved in many cellular processes • Overexpression of Myc is the cause of cancers like Leukemia, Lymphoma, and Osteosarcoma