Synergism between upregulation of Rab7 and inhibition of autophagic degradation caused by mycoplasma facilitates intracellular mycoplasma infection.
Following fusion of a mycoplasma with a host cell membrane, the inserted components of mycoplasma may then be transported through the endocytic pathway. However, the effects of mycoplasmas on the host cell endomembrane system are largely unknown. In this study, mycoplasma‑induced changes in the dynamics of endocytic and autophagic systems were investigated. Endocytosis and autophagy are two major processes involved in the survival of intracellular prokaryotic pathogens. It was found that, immediately following infection, mycoplasmas induce endocytosis in the host cell; however, in the long term the mycoplasmas suppress turnover of the components of the endocytic pathway. Immunofluorescence microscopy revealed that Rab7 and LC3‑II are recruited to the intracellular mycoplasma‑containing compartments. Western blot analysis and quantitative reverse transcription-polymerase chain reaction (qPCR) showed that mycoplasmas increase expression of Rab7 by upregulating transcription, but increase levels of LC3‑II and p62 by post‑translational regulation. Furthermore, it was demonstrated that mycoplasma infection causes inhibition of autophagic degradation of LC3‑II and p62. In addition, it was found that upregulation of Rab7 and inhibition of autophagic degradation synergistically contributes to intracellular mycoplasma accumulation. In conclusion, these findings suggest that mycoplasmas may manipulate host cell endosomal and autophagic systems in order to facilitate intracellular infection.
Department of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China.
Xiaopeng
X
Hu
First People's Hospital of Jiujiang City, Jiujiang, Jiangxi 330300, P.R. China.
Jie
J
Yu
The Fifth Hospital of Huangshi City, Huangshi, Hubei 435004, P.R. China.
Xiang
X
Zhou
Department of Oncology, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China.
Zhaoming
Z
Li
Department of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China.
Yun
Y
Xia
Department of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China.
Zhiyong
Z
Luo
Department of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China.
Yaqun
Y
Wu
D001343:Autophagy; D045744:Cell Line, Tumor; D004705:Endocytosis; D011992:Endosomes / Q000378:metabolism; D006367:HeLa Cells; D054884:Host-Pathogen Interactions / Q000502:physiology*; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism; D009174:Mycoplasma / Q000378:metabolism*; D009175:Mycoplasma Infections / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D010455:Peptides / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D015854:Up-Regulation; D020691:rab GTP-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D000090802:rab7 GTP-Binding Proteins
C477012:MAP1LC3A protein, human; D008869:Microtubule-Associated Proteins; C072437:P62 peptide; D010455:Peptides; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D000090802:rab7 GTP-Binding Proteins; C000716463:rab7 GTP-binding proteins, human; D020691:rab GTP-Binding Proteins