RESUMO
Congenital heart disease (CHD) is the most common birth defect, affecting approximately 1% of live births. Genetic and environmental factors are leading factors to CHD, but the mechanism of CHD pathogenesis remains unclear. Circular RNAs (circRNAs) are kinds of endogenous non-coding RNAs (ncRNAs) involved in a variety of physiological and pathological processes, especially in heart diseases. In this study, three significant differently expressed circRNA between maternal embryonic day (E) E13 and E17 was found by microarray assay. Among them, the content of circ-RCCD increases with the development of heart and was enriched in primary cardiomyocytes of different species, which arouses our attention. Functional experiments revealed that inhibition of circ-RCCD dramatically suppressed the formation of beating cell clusters, the fluorescence intensity of cardiac differentiation marker MF20, and the expression of the myocardial-specific markers CTnT, Mef2c, and GATA4. Next, we found that circ-RCCD was involved in cardiomyocyte differentiation through negative regulation of MyD88 expression. Further experiments proved that circ-RCCD inhibited MyD88 levels by recruiting YY1 to the promoter of MyD88; circ-RCCD inhibited nuclear translocation of YY1. These results reported that circ-RCCD promoted cardiomyocyte differentiation by recruiting YY1 to the promoter of MyD88. And, this study provided a potential role and molecular mechanism of circ-RCCD as a target for the treatment of CHD.
Assuntos
MicroRNAs , Fator 88 de Diferenciação Mieloide , RNA Circular , Fator de Transcrição YY1 , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proliferação de Células/genética , Desenvolvimento Embrionário , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Miócitos Cardíacos/metabolismo , Regiões Promotoras Genéticas , RNA Circular/genética , RNA Circular/metabolismo , Fator de Transcrição YY1/genética , Fator de Transcrição YY1/metabolismoRESUMO
OBJECTIVE: To solve the puzzle about the right size of the explant of wild medicinal plant Lycoris aurea for tissue culture. METHODS: Three-size explants: 9.0 x 8.0 mm, 6.0 x 5.0 mm, 3.0 x 2.0 mm of endothecium bulb-scale joined by a strip of stem plate and middle-layer bulb-scale joined by a strip of stem plate were cultured on two kinds of the medium: MS +9 mg/L BA +5 mg/ L NAA +0.7% agar +3% cane sugar and MS +5 mg/L BA +9 mg/L NAA +0.7% agar +3% cane sugar, and the culture effects of the three-size explants for Lycoris aurea were studied. RESULTS AND CONCLUSION: The results showed that the explant size on 6.0 x 5.0 mm of the endothecium bulb-scale cultured on the medium: MS +9 mg/L BA +5 mg/L NAA +0.7% agar +3% cane sugar had the advantage of forming adventitious buds and roots, and inhibiting brown samples, and to the middle-layer bulb-scale explant of the same size cultured on the same medium was next. Correlation analysis showed that the culture effect of the three-size explants on one kind of medium was significantly correlated with that of theirs on another kind of medium, which further proved that the result of Duncans multiple range test, i.e. if the effect of an explant size on one kind of medium were better, its effect on another kind of medium would also be better. Both Duncan's multiple range test and correlation analysis indicated that the effect of the size on 6.0 x 5.0 mm explant of the double endothecium bulb-scale joined by a strip of stem plate was better than those of the other sizes on the experimental explants, and to that of 6.0 x 5.0 mm size of the double middle-layer bulb-scale joined by a strip of stem plate was next.