PDGFR? translocates to the nucleus and regulates chromatin remodeling via TATA element-modifying factor 1.

ABSTRACT: Translocation of full-length or fragments of receptors to the nucleus has been reported for several tyrosine kinase receptors. In this paper, we show that a fraction of full-length cell surface platelet-derived growth factor (PDGF) receptor ? (PDGFR?) accumulates in the nucleus at the chromatin and the nuclear matrix after ligand stimulation. Nuclear translocation of PDGFR? was dependent on PDGF-BB-induced receptor dimerization, clathrin-mediated endocytosis, ?-importin, and intact Golgi, occurring in both normal and cancer cells. In the nucleus, PDGFR? formed ligand-inducible complexes with the tyrosine kinase Fer and its substrate, TATA element-modifying factor 1 (TMF-1). PDGF-BB stimulation decreased TMF-1 binding to the transcriptional regulator Brahma-related gene 1 (Brg-1) and released Brg-1 from the SWI-SNF chromatin remodeling complex. Moreover, knockdown of TMF-1 by small interfering RNA decreased nuclear translocation of PDGFR? and caused significant up-regulation of the Brg-1/p53-regulated cell cycle inhibitor CDKN1A (encoding p21) without affecting PDGFR?-inducible immediate-early genes. In conclusion, nuclear interactions of PDGFR? control proliferation by chromatin remodeling and regulation of p21 levels.

SUBMITTER: Papadopoulos N 

PROVIDER: S-EPMC5940298 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature