Reactive oxygen species mediate microRNA-302 regulation of AT-rich interacting domain 4a and C-C motif ligand 5 expression during transitions between quiescence and proliferation.
Normal cell growth consists of two distinct phases, quiescence and proliferation. Quiescence, or G(0), is a reversible growth arrest in which cells retain the ability to reenter the proliferative cycle (G(1), S, G(2), and M). Although not actively dividing, quiescent cells are metabolically active and quiescence is actively maintained. Our results from microRNA PCR arrays and Taqman PCR assays showed a significant decrease (4-fold) in miR-302 levels during quiescence compared to proliferating normal human fibroblasts, suggesting that miR-302 could regulate cellular proliferation. Results from a Q-RT-PCR and dual-luciferase-3'-UTR reporter assays identified ARID4a (AT-rich interacting domain 4a, also known as RBP1) and CCL5 (C-C motif ligand 5) as targets for miR-302. Ionizing radiation decreased miR-302 levels, which was associated with an increase in its target mRNA levels, ARID4a and CCL5. Such an inverse correlation was also observed in cells treated with hydrogen peroxide as well as SOD2-overexpressing cells. Overexpression of miR-302 suppresses ARID4a and CCL5 mRNA levels, and increased the percentage of S-phase cells. These results identified miR-302 as an ROS-sensitive regulator of ARID4a and CCL5 mRNAs as well as demonstrate a regulatory role of miR-302 during quiescence and proliferation.
Free Radical and Radiation Biology Division, B180 Medical Laboratories, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242-1181, USA.
Maneesh G
MG
Kumar
Neil M
NM
Patel
Adam M
AM
Nicholson
Amanda L
AL
Kalen
Ehab H
EH
Sarsour
Prabhat C
PC
Goswami
D020413:3' Untranslated Regions; D001483:Base Sequence; D002460:Cell Line; D049109:Cell Proliferation; D018946:Chemokine CCL5 / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D017930:Genes, Reporter; D006801:Humans; D049410:Luciferases, Renilla / Q000096:biosynthesis / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D056465:Retinoblastoma-Binding Protein 1 / Q000235:genetics* / Q000378:metabolism
D020413:3' Untranslated Regions; C533432:ARID4A protein, human; C483024:CCL5 protein, human; D018946:Chemokine CCL5; C532169:MIRN302A microRNA, human; D035683:MicroRNAs; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D056465:Retinoblastoma-Binding Protein 1; D049410:Luciferases, Renilla