miR-16 family induces cell cycle arrest by regulating multiple cell cycle genes

MicroRNAs (miRNAs) are a class of small regulatory RNAs that are thought to be involved in diverse biological processes by regulating gene expression. Numerous miRNAs have been identified in various species, and many more miRNAs remain to be detected. Generally, hundreds of mRNAs have been predicted to be potential targets of one miRNA, so it is a great challenge to identify the genuine miRNA targets. Here, we generated the cell lines depleted of Drosha protein and screened dozens of transcripts (including Cyclin D1) regulated potentially by miRNA-mediated RNA silencing pathway. On the basis of miRNA expressing library, we established a miRNA targets reverse screening method by using luciferase reporter assay. By this method, we found that the expression of Cyclin D1 (CCND1) was regulated by miR-16 family directly, and miR-16 induced G1 arrest in A549 cells partially by CCND1. Furthermore, several other cell cycle genes were revealed to be regulated by miR-16 family, including Cyclin D3 (CCND3), Cyclin E1 (CCNE1) and CDK6. Taken together, our data suggests that miR-16 family triggers an accumulation of cells in G0/G1 by silencing multiple cell cycle genes simultaneously, rather than the individual target

From Romantic Gothic to Victorian Medievalism: 1817 and 1877

"The Cambridge History of the Gothic was conceived in 2015, when Linda Bree, then Editorial Director at Cambridge University Press, first suggested the idea to us

MicroRNA miR-24 promotes cell proliferation by targeting the CDKs inhibitors p27Kip1 and p16INK4a

Cell cycle progression is controlled by numerous mechanisms ensuring correct cell division. The transition from one cell cycle phase to another occurs in an orderly fashion and is regulated by different cellular proteins. Therefore an alteration of the regulatory mechanisms of the cell cycle results in uncontrolled cell proliferation, which is a distinctive feature of human cancers. Recent evidences suggest that microRNAs (miRs) may also control the levels of multiple cell cycle regulators and therefore control cell proliferation. In fact miRs are a class of small non-coding RNAs, which modulate gene expression. They are involved in numerous physiological cellular processes and most importantly accumulating evidence indicates that many miRs are aberrantly expressed in human cancers. In this report we describe that miR-24 directly targets p27Kip1 and p16Ink4a in primary keratinocyte and in different cancer derived cell lines promoting their proliferation, suggesting that miR-24 is involved in cyclin-dependent kinase inhibitors post-transcriptional regulation and that upregulation of miR-24 may play a role in carcinogenesis. J. Cell. Physiol. 228: 2015-2023, 2013. (c) 2013 Wiley Periodicals, Inc