S6C). On the basis of the previous finding that most hepatocytes enter S phase by 36 hours after 2/3 PH in adult male C57BL/6 mice,[18] we speculated that lncRNA-LALR1 might play a role in the regulation of cell cycle events preceding S phase because its expression level peaked between 18 and 24 hours during liver regeneration (Fig. 2A). To gain further insight into the cell cycle of proliferating hepatocytes, we analyzed the expression of various cyclins. We found

that at 24, 36, and 72 hours after 2/3 PH, lncRNA-LALR1-down-regulated mice have lower expression of cyclin D1, E1, and A2, AZD2281 which are known to play a role in the G1 to S transition of hepatocytes during regeneration. Additionally, the expression of cyclin B1 was decreased at 72 hours (Fig. 4D). Furthermore, we did not find any difference in the expression levels of cyclin D1, E1, A2, and B1 at 120 hours. In addition, lower protein levels of these cyclins were found in lncRNA-LALR1-down-regulated mice at 24, 36, and 72 hours after 2/3 PH (Fig. S5F). We also found that

at 24, 36, and 72 hours after 2/3 PH, the lncRNA-LALR1-up-regulated mice had a higher expression of cyclin D1, E1, and A2. In addition, cyclin B1 expression was increased at 72 hours (Fig. S6D). Furthermore, we did not find any difference in the expression of cyclin D1, E1, A2, and B1 A-769662 supplier at 120 hours. Thus, all the results suggested that lncRNA-LALR1 enhanced liver regeneration in mice mainly at an early phase after surgery by accelerating cell cycle progression. To assess the repair of liver injury, we detected serum levels Rutecarpine of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) at 24, 72, and 168 hours after 2/3 PH. More serious liver

damage was documented in the control mice than in the lncRNA-LALR1-up-regulated mice (Fig. S6B). Because lncRNA-LALR1 increased at an early phase after 2/3 PH and HGF played a critical role in liver regeneration following partial hepatectomy,[3, 16] we wondered whether the increase in lncRNA-LALR1 expression was driven by HGF. The expression levels of lncRNA-LALR1 increased with the elevated concentrations of HGF (Fig. 5A). In addition, a correlation was observed between HGF and lncRNA-LALR1 in mouse livers at different timepoints (Fig. 5B). To examine the influence of HGF on lncRNA-LALR1 expression, we cloned the promoter of lncRNA-LALR1 (a region spanning −1,988 bp to +166 bp nucleotide relative to transcription site) into a pGL3 basic firefly luciferase reporter. As Fig. 5C indicates, HGF significantly increased the luciferase activity of this construct. The pGL3 basic firefly luciferase reporter was used as a negative control. These results demonstrated that HGF increased the expression of lncRNA-LALR1 by enhancing the activity of the lncRNA-LALR1 promoter. According to the results of the coexpression network and pathway analysis, lncRNA-LALR1 is associated with the Wnt/β-catenin pathway during liver regeneration.