Differentiation‐associated surface antigen variation in the ancient eukaryote Giardia lamblia

@article{Svrd1998DifferentiationassociatedSA,
  title={Differentiation‐associated surface antigen variation in the ancient eukaryote Giardia lamblia},
  author={Staffan G. Sv{\"a}rd and T C Meng and Michael L. Hetsko and J Michael McCaffery and Frances D. Gillin},
  journal={Molecular Microbiology},
  year={1998},
  volume={30}
}
Encystation of Giardia lamblia is required for survival outside the host, whereas excystation initiates infection. The dormant cyst was considered an adaptation to external survival and passage through the stomach. However, we found previously that trophozoites which had recovered after completion of the life cycle had switched their major variant surface protein (VSP), called TSA 417, but neither the timing nor the molecular mechanism of switching had been elucidated. Here we demonstrate that… 
Antigenic Variation in Giardia
TLDR
Giardia lamblia trophozoites undergo surface antigenic variation where one member of a family of related proteins, variant specific surface proteins (VSPs), is expressed but periodically replaced by another, essential for the development of immunity, immune selection, and immune evasion as well as biological selection.
Proteomics of Secretory and Endocytic Organelles in Giardia lamblia
TLDR
The first proteome of ESVs and PVs is defined using a novel strategy combining flow cytometry-based organelle sorting with in silico filtration of mass spectrometry data to provide further evidence for the formation of a cyst extracellular matrix with minimal complexity.
Antigenic variation in Giardia lamblia
TLDR
The characteristics of this fascinating mechanism are summarized, conflicting information regarding the structure of VSPs as it relates to the host's immune response is analysed, and the major issues that need to be resolved to fully understand antigenic variation in this important pathogen are highlighted.
Antigenic Variation of the VSP Genes of Giardia Lamblia
TLDR
Giardia undergoes surface antigenic variation in humans and animal model infections, a phenomenon that may account for both chronicity of infections and the relatively broad mammalian host specificity with genotypically identical organisms found in humans, cats, beavers, and other mammals.
Export of cyst wall material and Golgi organelle neogenesis in Giardia lamblia depend on endoplasmic reticulum exit sites
TLDR
The data show how ERES domains remain conserved in G. lamblia despite elimination of steady‐state Golgi, and the fundamental eukaryotic principle of ERES to Golgi/Golgi‐like compartment correspondence holds true in differentiating Giardia presenting streamlined machinery for secretory organelle biogenesis and protein trafficking.
Export of cyst wall material and Golgi organelle neogenesis in Giardia lamblia depends on ER exit sites 1
TLDR
The data show how ERES domains remain conserved in G. lamblia despite elimination of steady-state Golgi, and the fundamental eukaryotic principle of ERES to Golgi/Golgi-like compartment correspondence holds true in differentiating Giardia presenting streamlined machinery for secretory organelle biogenesis and protein trafficking.
Cell cycle and differentiation in Giardia Lamblia
TLDR
This work developed for the first time a method of synchronizing Giardia for use to determine where the encystation restriction point is in the cell cycle, and used quantitative real-time PCR to determine the periodic cell cycle regulation of histones.
Surface antigenic variation in Giardia lamblia
  • T. Nash
  • Biology, Medicine
    Molecular microbiology
  • 2002
Giardia lamblia , a common intestinal dwelling protozoan and a cause of diarrhoea in humans and animals world‐wide, undergoes surface antigenic variation. The variant‐specific surface proteins (VSPs)
Mining the Giardia lamblia Genome for New Cyst Wall Proteins*
TLDR
Five new LRR-containing proteins are identified, of which only one (CWP3) is up-regulated during encystation and incorporated into the cyst wall, demonstrating the power of genomics in combination with rigorous functional analyses to verify annotation.
The Giardia lamblia vsp gene repertoire: characteristics, genomic organization, and evolution
TLDR
The data presented here is the first comprehensive analysis of the vsp gene family from the Genotype A1 WB isolate with an emphasis on vsp characterization, function, evolution and contributions to pathogenesis of this important pathogen.
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