Cytoplasmic MTDH associates with mRNAs

To examine whether MTDH is a novel RNA binding protein and regulates either metabolism or translation of various mRNAs, we performed a RNA-binding protein immunoprecipitation (RIP) with MTDH and IgG antibodies, and the resulting immunoprecipitated RNA was subjected to a microarray to identify transcripts associating with MTDH. In addition we tested the effect of PI3K inhibition using BEZ235 (a dual PI3K/mTOR inhibitor) on the association of MTDH with target mRNAs. The microarray was performed on three biological triplicates as well as three experimental triplicates of immunoprecipitated MTDH and IgG in Hec50co endometrial cancer cells. Magna RIP (RNA-binding protein immunoprecipitation, Millipore) Kit and microarray were used to immunoprecipitate MTDH associated RNAs and to identify mRNAs that associate with MTDH in the absence or presence of 100nM BEZ235 (LC Labs). Fold changes represent immunoprecipitated MTDH RNA compared to IgG immunoprecipitated RNA. Representative mRNAs associated with MTDH and the effect of BEZ235 on the association of MTDH with mRNAs are shown.