npg Function of miR-27b in cardiac hypertrophy 526 ATGACAGACAGATCCCTCCTATCTCC-3′ and 5′-TCAGCACG CTGTTTGCACTCTT-3′. Western blot analysis Western blot was carried out on myocardial extracts as de- scribed [41]. 30 µg of proteins were electrophoresed on 12% SDS- PAGE and transferred onto PVDF membranes. Immunoblotting was performed according to the manufacturer’s instructions using the following antibodies: anti-PPAR-γ, anti-Smad4, anti-PAI-1 and anti-GAPDH (Santa Cruz). Transthoracic echocardiography and in vivo blood pressure measurement Cardiac function and heart dimensions were evaluated by echocardiography and in vivo blood pressure measurements as de- scribed [6]. Antagomir application on TAC models TAC surgeries were performed on male C57BL/6 mice (8 weeks old) as described [42]. Chemically modified antisense oli- gonucleotides (antagomir) were synthesized by GenePharma Co., Ltd. Treatments started 2 weeks after TAC, and animals received 0.2 ml saline, antagomir-27b (three injections in three consecutive days, 80 mg/kg body weight) via tail vein injections [31, 32]. Statistical analysis All statistical analyses were performed using SPSS software. Results are means ± SEM. Statistical differences were determined by Student’s t-test. P-value < 0.05 was considered significant. Other methods including miRNA northern blot, plasmid and adenovirus constructions, isolation of cardiomyocytes, real-time PCR, luciferase reporter assay, histology and immunohistology are described in Supplementary information, Data S1. Acknowledgments This work was supported by grants from the Chinese Key Program for Drug Invention (2009ZX09501-027), the Chinese National Key Program on Basic Research (2011CB504200) and the National Natural Science Foundation of China (31030040, 30700424, 30871364, 31071992, 81030001, 30971161). References 1 2 3 4 5 Heineke J, Molkentin JD. 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