p63-microRNA feedback in keratinocyte senescence.
We investigated the expression of microRNAs (miRNAs) associated with replicative senescence in human primary keratinocytes. A cohort of miRNAs up-regulated in senescence was identified by genome-wide miRNA profiling, and their change in expression was validated in proliferative versus senescent cells. Among these, miRNA (miR)-138, -181a, -181b, and -130b expression increased with serial passages. miR-138, -181a, and -181b, but not miR-130b, overexpression in proliferating cells was sufficient per se to induce senescence, as evaluated by inhibition of BrdU incorporation and quantification of senescence-activated β-galactosidase staining. We identified Sirt1 as a direct target of miR-138, -181a, and -181b, whereas ΔNp63 expression was inhibited by miR-130b. We also found that ΔNp63α inhibits miR-138, -181a, -181b, and -130b expression by binding directly to p63-responsive elements located in close proximity to the genomic loci of these miRNAs in primary keratinocytes. These findings suggest that changes in miRNA expression, by modulating the levels of regulatory proteins such as p63 and Sirt1, strongly contribute to induction of senescence in primary human keratinocytes, thus linking these two proteins. Our data also indicate that suppression of miR-138, -181a, -181b, and -130b expression is part of a growth-promoting strategy of ΔNp63α in epidermal proliferating cells.
Istituto Dermopatico dell'Immacolata-Istituto di Ricovero e Cura a Carattere Scientifico, Laboratory of Biochemistry, Department of Experimental Medicine and Biochemical Sciences, and University of Rome Tor Vergata, 00133 Rome, Italy.
Pia
P
Rivetti di Val Cervo
Anna Maria
AM
Lena
Milena
M
Nicoloso
Simona
S
Rossi
Mara
M
Mancini
Huiqing
H
Zhou
Gaelle
G
Saintigny
Elena
E
Dellambra
Teresa
T
Odorisio
Christian
C
Mahé
George Adrian
GA
Calin
Eleonora
E
Candi
Gerry
G
Melino
D015153:Blotting, Western; D001973:Bromodeoxyuridine; D002453:Cell Cycle / Q000502:physiology; D002460:Cell Line; D049109:Cell Proliferation; D016922:Cellular Senescence / Q000502:physiology*; D047369:Chromatin Immunoprecipitation; D019295:Computational Biology; D005434:Flow Cytometry; D005786:Gene Expression Regulation / Q000235:genetics* / Q000502:physiology*; D006801:Humans; D015603:Keratinocytes / Q000166:cytology* / Q000378:metabolism; D008156:Luciferases; D035683:MicroRNAs / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D056564:Sirtuin 1 / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D025521:Tumor Suppressor Proteins / Q000378:metabolism*; D001616:beta-Galactosidase
D035683:MicroRNAs; C115051:TP63 protein, human; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; D008156:Luciferases; D001616:beta-Galactosidase; C447939:SIRT1 protein, human; D056564:Sirtuin 1; D001973:Bromodeoxyuridine