Original ResearchFull Report: Basic and Translational—Alimentary TractMIR106B and MIR93 Prevent Removal of Bacteria From Epithelial Cells by Disrupting ATG16L1-Mediated Autophagy
Section snippets
Cell Lines
Human cell lines HCT116, SW480 (colon cancer), HeLa (cervical cancer), and U2OS (osteosarcoma) were maintained in the laboratory. HCT116/GFP-LC3, SW480/GFP-LC3, and U2OS/GFP-LC3 were parental cell lines stably transfected with GFP-LC3 and established in the laboratory.18 HCT116 cells were grown in McCoy's 5A medium with 10% fetal bovine serum (FBS). Other cells were cultured in Dulbecco's modified Eagle medium with l-glutamine and 10% FBS. HeLa/mCherry-LC3 cell line was established by stably
Silencing of Dicer Enhances the Expression of ATGs and Formation of Autophagosomes
To determine whether abrogation of miRNA biogenesis is sufficient to induce ATG expression and autophagy, small interfering RNA (siRNA)-mediated knockdown of Dicer was performed.22 We transfected Dicer1 siRNA into U2OS/GFP-LC3 cells, a cell line we previously established for monitoring autophagy.18 On serum starvation, GFP-LC3 in control cells redistributed from a diffuse cytoplasmic location (Figure 1Ai) to discrete vesicular structures (Figure 1Aii and iii), an indication of autophagy.18 The
Discussion
Autophagy has been shown to be essential for the clearance of intracellular microbes in mammalian cells.1, 2, 3, 4, 32 However, the underlying mechanism controlling autophagy in these cells remains unknown. We previously reported that the miR-106 cluster was among the miRNAs down-regulated during differentiation of human monocytes into dendritic cells.23 We also noted that ATG16L1 and ATG9 levels were substantially increased and that autophagy was markedly induced during differentiation of
Acknowledgments
The authors thank Dr Philip M. Sherman (Research Institute of Hospital for Sick Children, Toronto, Ontario, Canada) for providing the AIEC strain LF82, Dr Ramnik Xavier (Harvard University) for providing the original FLAG-ATG16L1 plasmid, and Drs Xuxian Xiao, Weiming Zhang, and Jian Wang in the Xu Laboratory for critical technical support.
References (41)
- et al.
Methods in mammalian autophagy research
Cell
(2010) - et al.
Autophagy, immunity, and microbial adaptations
Cell Host Microbe
(2009) - et al.
Role of the Apg12 conjugation system in mammalian autophagy
Int J Biochem Cell Biol
(2003) - et al.
miR-221 and miR-155 regulate human dendritic cell development, apoptosis, and IL-12 production through targeting of p27kip1, KPC1, and SOCS-1
Blood
(2011) - et al.
MiR-17/20/93/106 promote hematopoietic cell expansion by targeting sequestosome 1-regulated pathways in mice
Blood
(2011) - et al.
MiR-20a and miR-106b negatively regulate autophagy induced by leucine deprivation via suppression of ULK1 expression in C2C12 myoblasts
Cell Signal
(2012) - et al.
Micro-RNAs as regulators and possible diagnostic bio-markers in inflammatory bowel disease
J Crohns Colitis
(2011) - et al.
Regulation mechanisms and signaling pathways of autophagy
Annu Rev Genet
(2009) - et al.
Autophagy in immunity against intracellular bacteria
Curr Top Microbiol Immunol
(2009) - et al.
A key role for autophagy and the autophagy gene Atg16l1 in mouse and human intestinal Paneth cells
Nature
(2008)
Autophagy and its role in MHC-mediated antigen presentation
J Immunol
Molecular basis of canonical and bactericidal autophagy
Int Immunol
Crohn's disease-associated adherent-invasive E. coli are selectively favoured by impaired autophagy to replicate intracellularly
Cell Microbiol
Impaired autophagy of an intracellular pathogen induced by a Crohn's disease associated ATG16L1 variant
PLoS One
Epidemiology and natural history of inflammatory bowel diseases
Gastroenterology
Genome-wide association study identifies new susceptibility loci for Crohn disease and implicates autophagy in disease pathogenesis
Nat Genet
Host-microbe interactions have shaped the genetic architecture of inflammatory bowel disease
Nature
Genome-wide meta-analysis increases to 71 the number of confirmed Crohn's disease susceptibility loci
Nat Genet
A microRNA polycistron as a potential human oncogene
Nature
c-Myc-regulated microRNAs modulate E2F1 expression
Nature
Cited by (97)
3-Epi-betulinic acid 3-O-β-D-glucopyranoside (eBAG) induces autophagy by activation of AMP-activated protein kinase in hepatocellular carcinoma
2024, Food Science and Human WellnessEpigenetic regulation of autophagy in coronavirus disease 2019 (COVID-19)
2022, Biochemistry and Biophysics ReportsInterplay between gut microbiota and autophagy in human health
2022, Autophagy and Metabolism: Potential Target for Cancer TherapyFermented products and bioactive food compounds as a tool to activate autophagy and promote the maintenance of the intestinal barrier function
2021, Trends in Food Science and TechnologyCitation Excerpt :In turn, Escherichia coli, so-called adherent-invasive E. coli (AIEC), poses a huge challenge in the treatment of patients with IBD. AIEC inhibits autophagy, as shown in studies on human cell lines, where it inhibited the expression of ATG16L1 (Lu et al., 2014; Meconi et al., 2007). Given that xenophagy should ensure the elimination of pathogens, it would be expected that the immune response modulated by the microbiota runs smoothly with the participation of commensal microbes.
Autophagy in the gastrointestinal system and cross talk with microbiota
2021, Autophagy in Health and DiseaseEpigenetic targeting of autophagy for cancer prevention and treatment by natural compounds
2020, Seminars in Cancer Biology
Author names in bold designate shared co-first authorship
Conflicts of interest The authors disclose no conflicts.
Funding Supported by National Cancer Institute grant R01CA133053, the National Cancer Institute Cervical Cancer SPORE Career Development Award and Pilot Award P50CA098252 (to Z.-X.X.), and National Institute of Allergy and Infectious Diseases grant R21AI092220 (to X.Z.).
- ∗
Authors share co-first authorship