Cardiomyocyte-Specific RhoA Knockout Mice

RhoA-floxed mice (RhoA^fl/fl: C57BL/6 background), in which exon 3 of the Rhoa gene was flanked by loxP sites, were generated and used in our previous study (46 (link)). The mice were then mated with C57BL/6 mice expressing Cre recombinase under the control of the α-myosin heavy chain promoter (Myh6-Cre; Jackson Laboratory) to generate cardiomyocyte-specific RhoA cKO mice. In the Myh6-Cre mice, Cre exerts its recombination activity specifically in cardiomyocytes but not in other tissues such as the liver, lung, skeletal muscle, and spleen (47 (link)), and the recombinase functions from embryonic day 9.5 (48 (link)). Mice harboring RhoA^fl/fl alleles alone were used as controls. The mice were housed in specific pathogen-free conditions at the Research Centre for Animal Life Science of Shiga University of Medical Science. All animal protocols were in accordance with institutional guidelines, including Animal Research Reporting of In Vivo Experiments (ARRIVE) guidelines, and were approved by the Animal Care and Use Committee of Shiga University of Medical Science (No. 2020-9-8).