TY - JOUR
T1 - MiR-133 promotes cardiac reprogramming by directly repressing Snai1 and silencing fibroblast signatures
AU - Muraoka, Naoto
AU - Yamakawa, Hiroyuki
AU - Miyamoto, Kazutaka
AU - Sadahiro, Taketaro
AU - Umei, Tomohiko
AU - Isomi, Mari
AU - Nakashima, Hanae
AU - Akiyama, Mizuha
AU - Wada, Rie
AU - Inagawa, Kohei
AU - Nishiyama, Takahiko
AU - Kaneda, Ruri
AU - Fukuda, Toru
AU - Takeda, Shu
AU - Tohyama, Shugo
AU - Hashimoto, Hisayuki
AU - Kawamura, Yoshifumi
AU - Goshima, Naoki
AU - Aeba, Ryo
AU - Yamagishi, Hiroyuki
AU - Fukuda, Keiichi
AU - Ieda, Masaki
PY - 2014/7/17
Y1 - 2014/7/17
N2 - Fibroblasts can be directly reprogrammed into cardiomyocyte-like cells (iCMs) by overexpression of cardiac transcription factors or microRNAs. However, induction of functional cardiomyocytes is inefficient, and molecular mechanisms of direct reprogramming remain undefined. Here, we demonstrate that addition of miR-133a (miR-133) to Gata4, Mef2c, and Tbx5 (GMT) or GMT plus Mesp1 and Myocd improved cardiac reprogramming from mouse or human fibroblasts by directly repressing Snai1, a master regulator of epithelial-to-mesenchymal transition. MiR-133 overexpression with GMT generated sevenfold more beating iCMs from mouse embryonic fibroblasts and shortened the duration to induce beating cells from 30 to 10 days, compared to GMT alone. Snai1 knockdown suppressed fibroblast genes, upregulated cardiac gene expression, and induced more contracting iCMs with GMT transduction, recapitulating the effects of miR-133 overexpression. In contrast, overexpression of Snai1 in GMT/miR-133-transduced cells maintained fibroblast signatures and inhibited generation of beating iCMs. MiR-133-mediated Snai1 repression was also critical for cardiac reprogramming in adult mouse and human cardiac fibroblasts. Thus, silencing fibroblast signatures, mediated by miR-133/Snai1, is a key molecular roadblock during cardiac reprogramming.
AB - Fibroblasts can be directly reprogrammed into cardiomyocyte-like cells (iCMs) by overexpression of cardiac transcription factors or microRNAs. However, induction of functional cardiomyocytes is inefficient, and molecular mechanisms of direct reprogramming remain undefined. Here, we demonstrate that addition of miR-133a (miR-133) to Gata4, Mef2c, and Tbx5 (GMT) or GMT plus Mesp1 and Myocd improved cardiac reprogramming from mouse or human fibroblasts by directly repressing Snai1, a master regulator of epithelial-to-mesenchymal transition. MiR-133 overexpression with GMT generated sevenfold more beating iCMs from mouse embryonic fibroblasts and shortened the duration to induce beating cells from 30 to 10 days, compared to GMT alone. Snai1 knockdown suppressed fibroblast genes, upregulated cardiac gene expression, and induced more contracting iCMs with GMT transduction, recapitulating the effects of miR-133 overexpression. In contrast, overexpression of Snai1 in GMT/miR-133-transduced cells maintained fibroblast signatures and inhibited generation of beating iCMs. MiR-133-mediated Snai1 repression was also critical for cardiac reprogramming in adult mouse and human cardiac fibroblasts. Thus, silencing fibroblast signatures, mediated by miR-133/Snai1, is a key molecular roadblock during cardiac reprogramming.
KW - Snai1
KW - cardiomyocyte
KW - microRNA
KW - reprogramming
KW - transcription factor
UR - http://www.scopus.com/inward/record.url?scp=84904580766&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84904580766&partnerID=8YFLogxK
U2 - 10.15252/embj.201387605
DO - 10.15252/embj.201387605
M3 - Article
C2 - 24920580
AN - SCOPUS:84904580766
SN - 0261-4189
VL - 33
SP - 1565
EP - 1581
JO - EMBO Journal
JF - EMBO Journal
IS - 14
ER -