Related Experiment Video

Updated: Feb 20, 2026

Affinity Precipitation of Active Rho-GEFs Using a GST-tagged Mutant Rho Protein GST-RhoAG17A from Epithelial Cell Lysates
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Affinity Precipitation of Active Rho-GEFs Using a GST-tagged Mutant Rho Protein GST-RhoAG17A from Epithelial Cell Lysates

Published on: March 31, 2012

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Nε-Fatty acylation of Rho GTPases by a MARTX toxin effector

Yan Zhou1, Chunfeng Huang1, Li Yin1

  • 1Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou, Zhejiang 310058, China.

Science (New York, N.Y.)
|October 28, 2017
PubMed

Insights

Bacterial toxins called MARTX toxins release effector domains into host cells. One domain, RID, acts as a fatty acyltransferase, modifying Rho GTPases and disrupting host cell signaling.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Biochemistry

Background:

  • Multifunctional autoprocessing repeats-in-toxin (MARTX) toxins are prevalent in bacterial pathogens.
  • These toxins cleave into effector domains that modulate host signaling pathways.

Purpose of the Study:

  • To investigate the function of the Rho GTPase inactivation domain (RID) of MARTX toxins.
  • To elucidate the mechanism by which RID disrupts host actin cytoskeleton and causes cell rounding.

Main Methods:

  • Biochemical assays to determine the enzymatic activity of RID.
  • Analysis of Rho GTPase modification in host cells.

Main Results:

  • RID functions as an Nε-fatty acyltransferase.
  • RID covalently modifies lysine residues in the C-terminal polybasic region of Rho GTPases.
  • Fatty acylation of Rho GTPases inhibits their activity and disrupts downstream signaling.

Conclusions:

  • RID mediates lysine Nε-fatty acylation of mammalian proteins.
  • MARTX toxins represent a novel family of bacterial toxins with N-fatty acyltransferase activity.

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