RET oncoproteins induce tyrosine phosphorylation changes of proteins involved in RNA metabolism.

Abstract

We report the identification of proteins induced in response to RET/PTC2, an oncogene implicated in thyroid cancers. Anti-phosphotyrosine antibody affinity resin was used to purify Tyr(P)-containing and interacting proteins from 293T and NIH3T3 cells which were transfected with kinase active or inactive RET/PTC and RETMEN2 oncogenes. Proteins were separated by one-dimensional SDS-PAGE, extracted by in-gel digestion, and identified by MALDI-TOF peptide mass fingerprinting. The expression and tyrosine phosphorylation of Sam68, a protein implicated in mRNA nucleocytoplasmic translocation and splicing, were further examined in RET-transfected cells and thyroid tumors. Of relevance, cells transfected with RETMEN2B examined for anti-phosphotyrosine bound proteins, showed other proteins implicated in splicing: DEAD-box p68 RNA helicase, SYNCRIP, and hnRNP K. Western blotting analysis suggested that these proteins are singularly tyrosine phosphorylated in RETMEN2B-transfected cells, and that they constitutively bind with Sam68. The study concludes that regulation of splicing factors is likely to be important in RET-mediated thyroid carcinogenesis.

• Authors: L Gorla, M Cantù, F Miccichè, C Patelli, P Mondellini, M A Pierotti, I Bongarzone
• Journal: Cellular signalling (Cell Signal) Vol. 18 Issue 12 Pg. 2272-82 (Dec 2006) ISSN: 0898-6568 [Print] England
• PMID: 16843637 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Adaptor Proteins, Signal Transducing
• DNA-Binding Proteins
• KHDRBS1 protein, human
• Protein Isoforms
• Proteins
• RNA-Binding Proteins
• Tyrosine
• RNA
• Proto-Oncogene Proteins c-ret

Topics

• Adaptor Proteins, Signal Transducing (genetics, metabolism)
• Alternative Splicing
• Animals
• Biological Transport
• Blotting, Western
• Cell Line
• Cell Line, Tumor
• Cell Nucleus (metabolism)
• Cytoplasm (metabolism)
• DNA-Binding Proteins (genetics, metabolism)
• Electrophoresis, Polyacrylamide Gel
• Humans
• Immunoprecipitation
• Mice
• Models, Biological
• Multiple Endocrine Neoplasia Type 2b (genetics, metabolism)
• NIH 3T3 Cells
• Phosphorylation
• Protein Isoforms (genetics, metabolism)
• Proteins (analysis, isolation & purification, metabolism)
• Proto-Oncogene Proteins c-ret (genetics, metabolism)
• RNA (metabolism)
• RNA-Binding Proteins (genetics, metabolism)
• Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
• Thyroid Gland (metabolism, pathology)
• Transfection
• Tyrosine (metabolism)