title: Novel interactions between NFATc1 (Nuclear Factor of Activated T cells c1) and STAT-3 (Signal Transducer and Activator of Transcription-3) mediate G protein-coupled receptor agonist, thrombin-induced biphasic expression of cyclin D1, with first phase influencing cell migration and second phase directing cell proliferation.
abstract: Thrombin, a G protein-coupled receptor agonist, induced a biphasic expression of cyclin D1 in primary vascular smooth muscle cells. Although both phases of cyclin D1 expression require binding of the newly identified cooperative complex, NFATc1·STAT-3, to its promoter, the second phase, which is more robust, depends on NFATc1-mediated recruitment of p300 onto the complex and the subsequent acetylation of STAT-3. In addition, STAT-3 is tyrosine-phosphorylated in a biphasic manner, and the late phase requires NFATc1-mediated p300-dependent acetylation. Furthermore, interference with acetylation of STAT-3 by overexpression of acetylation null STAT-3 mutant led to the loss of the late phase of cyclin D1 expression. EMSA analysis and reporter gene assays revealed that NFATc1·STAT-3 complex binding to the cyclin D1 promoter led to an enhanceosome formation and facilitated cyclin D1 expression. In the early phase of its expression, cyclin D1 is localized mostly in the cytoplasm and influenced cell migration. However, during the late and robust phase of its expression, cyclin D1 is translocated to the nucleus and directed cell proliferation. Together, these results demonstrate for the first time that the dual function of cyclin D1 in cell migration and proliferation is temperospatially separated by its biphasic expression, which is mediated by cooperative interactions between NFATc1 and STAT-3.
authors.affiliation: Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA.
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Kundumani-Sridharan
authors.forename: Dong
authors.initials: D
authors.lastname: Van Quyen
authors.forename: Jaganathan
authors.initials: J
authors.lastname: Subramani
authors.forename: Nikhlesh K
authors.initials: NK
authors.lastname: Singh
authors.forename: Y Eugene
authors.initials: YE
authors.lastname: Chin
authors.forename: Gadiparthi N
authors.initials: GN
authors.lastname: Rao
mesh_terms: D000107:Acetylation; D000818:Animals; D001483:Base Sequence; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D019938:Cyclin D1 / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology; D008297:Male; D008969:Molecular Sequence Data; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D050778:NFATC Transcription Factors / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000502:physiology; D051381:Rats; D043562:Receptors, G-Protein-Coupled / Q000819:agonists / Q000378:metabolism; D050796:STAT3 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D013917:Thrombin / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D050778:NFATC Transcription Factors; D043562:Receptors, G-Protein-Coupled; D050796:STAT3 Transcription Factor; C494088:Stat3 protein, rat; D019938:Cyclin D1; D013917:Thrombin