Intestinal stem cells(ISCs)initiate intestinal epithelial regeneration and tumorigenesis,and they experi-ence rapid refilling upon various injuries for epithelial repair as well as tumor reoccurrence.It is crucial to ...Intestinal stem cells(ISCs)initiate intestinal epithelial regeneration and tumorigenesis,and they experi-ence rapid refilling upon various injuries for epithelial repair as well as tumor reoccurrence.It is crucial to reveal the mechanism underlying such plasticity for intestinal health.Recent studies have found that metabolic pathways control stem cell fate in homeostasis,but the role of metabolism in the regeneration of ISCs after damage has not been clarified.Here,we find that in a human colorectal cancer dataset,miR-29a and b(miR-29a/b)are metabolic regulators highly associated with intestinal tumorigenesis and worse prognostic value of radiotherapy.We also show that these two microRNAs are required for intesti-nal stemness maintenance in mice,and their expression is induced in regenerated ISCs after irradiation injury,resulting in skewed ISC fate from differentiation towards self-renewal.This upregulation of miR-29a/b expression in ISCs leads to suppression of fatty acid oxidation(FAO)and depression of oxidative phosphorylation,which in turn controls the balance between self-renewal and differentiation of ISCs.Deletion of miR-29a/b prevents these effects and thus impairs ISC-mediated epithelial recovery.Finally,we filter the potential targets of miR-29a/b and identify Hnf4g,a transcription factor,that drives this metabolic reprogramming through regulating FAO-related enzymes.Our work discovers an impor-tant metabolic mechanism of ISC-mediated regeneration and potentially pave the way for more targeted and effective therapeutic strategies for intestinal repair as well as tumor treatment.展开更多
AIM To investigate the functional role and underlying molecular mechanism of mi R-29 a in hepatitis B virus(HBV) expression and replication.METHODS The levels of mi R-29 a and SMARCE1 in HBV-infected Hep G2.2.15 cells...AIM To investigate the functional role and underlying molecular mechanism of mi R-29 a in hepatitis B virus(HBV) expression and replication.METHODS The levels of mi R-29 a and SMARCE1 in HBV-infected Hep G2.2.15 cells were measured by quantitative real-time PCR and western blot analysis. HBV DNA replication was measured by quantitative PCR and Southern blot analysis. The relative levels of hepatitis B surface antigen and hepatitis B e antigen were detected by enzyme-linked immunosorbent assay. The Cell Counting Kit-8(CCK-8) was used to detect the viability of Hep G2.2.15 cells. The relationship between mi R-29 a and SMARCE1 were identified by target prediction and luciferase reporter analysis.RESULTS mi R-29 a promoted HBV replication and expression, w h i le S MA R C E 1 r e p r e s s e d H B V r e p lic a t io n a n d expression. Cell viability detection indicated that mi R-29 a transfection had no adverse effect on the host cells. Moreover, SMARCE1 was identified and validated to be a functional target of mi R-29 a. Furthermore, restored expression of SMARCE1 could relieve the increased HBV replication and expression caused by mi R-29 a overexpression.CONCLUSION mi R-29 a promotes HBV replication and expression through regulating SMARCE1. As a potential regulator of HBV replication and expression, mi R-29 a could be a promising therapeutic target for patients with HBV infection.展开更多
基金supported by the National Natural Science Foundation of China(32372247)the National Key Research and Development Program of China(2023YFF1104501)to Huiyuan Guo.
文摘Intestinal stem cells(ISCs)initiate intestinal epithelial regeneration and tumorigenesis,and they experi-ence rapid refilling upon various injuries for epithelial repair as well as tumor reoccurrence.It is crucial to reveal the mechanism underlying such plasticity for intestinal health.Recent studies have found that metabolic pathways control stem cell fate in homeostasis,but the role of metabolism in the regeneration of ISCs after damage has not been clarified.Here,we find that in a human colorectal cancer dataset,miR-29a and b(miR-29a/b)are metabolic regulators highly associated with intestinal tumorigenesis and worse prognostic value of radiotherapy.We also show that these two microRNAs are required for intesti-nal stemness maintenance in mice,and their expression is induced in regenerated ISCs after irradiation injury,resulting in skewed ISC fate from differentiation towards self-renewal.This upregulation of miR-29a/b expression in ISCs leads to suppression of fatty acid oxidation(FAO)and depression of oxidative phosphorylation,which in turn controls the balance between self-renewal and differentiation of ISCs.Deletion of miR-29a/b prevents these effects and thus impairs ISC-mediated epithelial recovery.Finally,we filter the potential targets of miR-29a/b and identify Hnf4g,a transcription factor,that drives this metabolic reprogramming through regulating FAO-related enzymes.Our work discovers an impor-tant metabolic mechanism of ISC-mediated regeneration and potentially pave the way for more targeted and effective therapeutic strategies for intestinal repair as well as tumor treatment.
文摘AIM To investigate the functional role and underlying molecular mechanism of mi R-29 a in hepatitis B virus(HBV) expression and replication.METHODS The levels of mi R-29 a and SMARCE1 in HBV-infected Hep G2.2.15 cells were measured by quantitative real-time PCR and western blot analysis. HBV DNA replication was measured by quantitative PCR and Southern blot analysis. The relative levels of hepatitis B surface antigen and hepatitis B e antigen were detected by enzyme-linked immunosorbent assay. The Cell Counting Kit-8(CCK-8) was used to detect the viability of Hep G2.2.15 cells. The relationship between mi R-29 a and SMARCE1 were identified by target prediction and luciferase reporter analysis.RESULTS mi R-29 a promoted HBV replication and expression, w h i le S MA R C E 1 r e p r e s s e d H B V r e p lic a t io n a n d expression. Cell viability detection indicated that mi R-29 a transfection had no adverse effect on the host cells. Moreover, SMARCE1 was identified and validated to be a functional target of mi R-29 a. Furthermore, restored expression of SMARCE1 could relieve the increased HBV replication and expression caused by mi R-29 a overexpression.CONCLUSION mi R-29 a promotes HBV replication and expression through regulating SMARCE1. As a potential regulator of HBV replication and expression, mi R-29 a could be a promising therapeutic target for patients with HBV infection.
