Sirt1 is regulated by miR-135a and involved in DNA damage repair during mouse cellular reprogramming

Abstract

Sirt1 facilitates the reprogramming of mouse somatic cells into induced pluripotent stem cells (iPSCs). It is regulated by micro-RNA and reported to be a target of miR-135a. However, their relationship and roles on cellular reprogramming remain unknown. In this study, we found negative correlations between miR-135a and Sirt1 during mouse embryonic stem cells differentiation and mouse embryonic fibroblasts reprogramming. We further found that the reprogramming efficiency was reduced by the overexpression of miR-135a precursor but induced by the miR-135a inhibitor. Co-immunoprecipitation followed by mass spectrometry identified 21 SIRT1 interacting proteins including KU70 and WRN, which were highly enriched for DNA damage repair. In accordance, Sirt1 activator resveratrol reduced DNA damage during the reprogramming process. Wrn was regulated by miR-135a and resveratrol partly rescued the impaired reprogramming efficiency induced by Wrn knockdown. This study showed Sirt1, being partly regulated by miR-135a, bound proteins involved in DNA damage repair and enhanced the iPSCs production.

Spermidine Retarded the Senescence of Multipotent Mesenchymal Stromal Cells In Vitro and In Vivo through SIRT3-Mediated Antioxidation

“…Notably, early SPD intervention slowed down the process significantly. Moreover, oxidative stress induces DNA damage and telomere dysfunction is an important mechanism of cell senescence [59][60][61][62][63][64]. Herein, visualized γ-H2AX immunofluorescence staining was performed to detect the DNA damage.…”

DNA Damage Response and Cell Cycle Regulation in Pluripotent Stem Cells

“…Among the sirtuin members, SIRT1 is the most widely studied molecule. It is detected in the nucleus and involved in many cellular events including transcriptional silencing, DNA damage repair, cell cycle regulation, insulin regulation and longevity [56][57][58][59][60]. As a histone deacetylase, SIRT1 is recruited to the chromatin and deacetylates histone 1 lysine 26 (H1K26), H3K9, H3K14 and H4K16 [61].…”

“…In addition, SIRT1 also deacetylates a number of transcription factors, including P53, FOXO, p300 histone acetyltransferase and E2F transcription factor 1 (E2F1) [62]. We and others have demonstrated that SIRT1 is highly expressed in both mESCs and hESCs [56,57,63]. In the following section, we review the importance of SIRT1 in regulating cell cycle progression and DDR.…”

“…Recently, we found that miR-135a regulated SIRT1 expression during miPSCs reprogramming. By immunoprecipitation, SIRT1 was found to interact with Wrn and Ku70 to form a protein complex in the initial phase of reprogramming [56]. The Wrn protein interacts with the Ku70/80 heterodimer [69], indicating that Wrn has a direct role in NHEJ.…”

Interphase Chromosomes in Replicative Senescence: Chromosome Positioning as a Senescence Biomarker and the Lack of Nuclear Motor-Driven Chromosome Repositioning in Senescent Cells

“…In replicative senescence (RS), cells reach senescence through serial division, and are permanently arrested although metabolically active ( Hayflick and Moorhead, 1961 ). RS cells display telomere shortening ( Harley et al, 1990 ; Allsopp et al, 1995 ; Blackburn, 2001 ; Cawthon et al, 2003 ; Masutomi et al, 2003 ; Ben-Porath and Weinberg, 2004 ; Ogami et al, 2004 ; Davis and Kipling, 2005 ; Canela et al, 2007 ), with accumulation of DNA damage through an inability to repair it ( Chen et al, 2020 ), de-repression of p16 INK 4a loci ( Zindy et al, 1997 ; Chkhotua et al, 2003 ; Krishnamurthy et al, 2004 ; Ressler et al, 2006 ) and alterations in Rb/p13 or p53/p21 CIP 1 pathways, both inducing senescence in different ways ( Chen et al, 2020 ). Oxidative stress-induced premature senescence (SIPS) is elicited through external or internal metabolic oxidative agents, causing severe or irreparable DNA damage ( te Poele et al, 2002 ; d’Adda di Fagagna et al, 2003 ; Parrinello et al, 2003 ; Bartkova et al, 2006 ; Di Micco et al, 2006 ).…”