Sodium butyrate down-regulates Tristetraprolin-mediated cyclin B1 expression independent of the formation of processing bodies.

Sodium butyrate down-regulates Tristetraprolin-mediated cyclin B1 expression independent of the formation of processing bodies. Int J Biochem Cell Biol. 2015 Nov 6; Authors: Zheng XT, Xiao XQ Abstract Butyrate regulates multiple host cellular events including the cell cycle; however, little is known about the molecular mechanism by which butyrate induces a global down-regulation of the expression of genes associated with the cell cycle. Here, we demonstrate that treating HEK293T cells and the non-small-cell lung cancer cell line A549 with a high concentration of sodium butyrate reduces cyclin B1 expression. The underlying mechanism is related to the destabilization of its mRNA by tristetraprolin, which is up-regulated in response to sodium butyrate. Specifically, the sodium butyrate stimulation reduces the mRNA and protein expression of cyclin B1 and, conversely, upregulates tristetraprolin expression. Importantly, the overexpression of tristetraprolin in HEK293T decreases the mRNA and protein expression of cyclin B1; in contrast, knockdown of tristetraprolin mediated by small interfering RNA increases its expression in response to sodium butyrate treatment for both HEK293T and A549 cells. Furthermore, results from luciferase reporter assays and RNA immunoprecipitation indicate that sodium butyrate accelerates 3' UTR-dependent cyclin B1 decay by enhancing the binding of tristetraprolin to the 3' untranslated region of cyclinB1. Surpr...
Source: The International Journal of Biochemistry and Cell Biology - Category: Biochemistry Authors: Tags: Int J Biochem Cell Biol Source Type: research