Home > Research > Publications & Outputs > Expression of GIMAP1, a GTPase of the immunity-...


Text available via DOI:

View graph of relations

Expression of GIMAP1, a GTPase of the immunity-associated protein family, is not up-regulated in malaria

Research output: Contribution to Journal/MagazineJournal articlepeer-review

  • Amy Saunders
  • Tracey Lamb
  • John Pascall
  • Amanda Hutchings
  • Carine Dion
  • Christine Carter
  • Lucy Hepburn
  • Jean Langhorne
  • Geoffrey W Butcher
Article number53
<mark>Journal publication date</mark>2/04/2009
<mark>Journal</mark>Malaria Journal
Publication StatusPublished
<mark>Original language</mark>English


BACKGROUND: GIMAP (GTPase of the immunity-associated protein family) proteins are a family of putative GTPases believed to be regulators of cell death in lymphomyeloid cells. GIMAP1 was the first reported member of this gene family, identified as a gene up-regulated at the RNA level in the spleens of mice infected with the malarial parasite, Plasmodium chabaudi.

METHODS: A monoclonal antibody against mouse GIMAP1 was developed and was used to analyse the expression of the endogenous protein in tissues of normal mice and in defined sub-populations of cells prepared from lymphoid tissues using flow cytometry. It was also used to assess the expression of GIMAP1 protein after infection and/or immunization of mice with P. chabaudi. Real-time PCR analysis was employed to measure the expression of GIMAP1 for comparison with the protein level analysis.

RESULTS: GIMAP1 protein expression was detected in all lineages of lymphocytes (T, B, NK), in F4/80+ splenic macrophages and in some lymphoid cell lines. Additional evidence is presented suggesting that the strong expression by mature B cells of GIMAP1 and other GIMAP genes and proteins seen in mice may be a species-dependent characteristic. Unexpectedly, no increase was found in the expression of GIMAP1 in P. chabaudi infected mice at either the mRNA or protein level, and this remained so despite applying a number of variations to the protocol.

CONCLUSION: The model of up-regulation of GIMAP1 in response to infection/immunization with P. chabaudi is not a robustly reproducible experimental system. The GIMAP1 protein is widely expressed in lymphoid cells, with an interesting increase in expression in the later stages of B cell development. Alternative approaches will be required to define the functional role of this GTPase in immune cells.