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A High-content Assay for Monitoring AMPA Receptor Trafficking
10:34

A High-content Assay for Monitoring AMPA Receptor Trafficking

Published on: January 28, 2019

De-AMPylation unmasked: modulation of host membrane trafficking

Hyeilin Ham1, Kim Orth

  • 1Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.

Science Signaling
|October 13, 2011
PubMed

Insights

Bacterial pathogen Legionella pneumophila uses SidD to reverse AMPylation of the host protein Rab1. This de-AMPylation by SidD allows for Rab1 inactivation, revealing a complete pathway for modulating host membrane trafficking during infection.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Cell Biology

Background:

  • Bacterial pathogens subvert host signaling via posttranslational modifications like AMPylation.
  • Legionella pneumophila effector SidM activates and AMPylates host Rab1 GTPase to manipulate vesicular trafficking.

Purpose of the Study:

  • To elucidate the mechanism of Rab1 inactivation and removal from Legionella-containing vacuoles.
  • To identify the bacterial enzyme responsible for reversing Rab1 AMPylation.

Main Methods:

  • Investigated the function of the Legionella pneumophila effector protein SidD.
  • Assayed the enzymatic activity of SidD in vitro and in host cells.
  • Utilized biochemical and cell-based assays to track Rab1 modification and localization.

Main Results:

  • Identified SidD as a de-AMPylase that removes AMP from Rab1.
  • Demonstrated that SidD-mediated de-AMPylation enables subsequent inactivation of Rab1 by LepB.
  • Showcased a reversible modification pathway controlling host membrane trafficking.

Conclusions:

  • SidD plays a crucial role in the Legionella infection cycle by reversing Rab1 AMPylation.
  • This reversible modification pathway allows for precise control of host membrane trafficking by L. pneumophila.
  • The findings reveal a complete bacterial enzyme-regulated system for modulating host cell processes.

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