Moonlighting glycolytic protein glyceraldehyde-3-phosphate dehydrogenase (GAPDH): an evolutionarily conserved

Anoop Singh Chauhan1, Manoj Kumar1, Surbhi Chaudhary1

  • 1Institute of Microbial Technology, Council of Scientific and Industrial Research, Chandigarh, India.

Insights

Mammalian cells use glyceraldehyde-3-phosphate dehydrogenase (GAPDH) to capture plasminogen (Plg) for inflammatory cell migration. This conserved protein aids macrophage recruitment to combat pathogens, highlighting a dual role in host defense and microbial invasion.

Area of Science:

  • Biochemistry
  • Cell Biology
  • Immunology

Background:

  • Prokaryotic pathogens hijack plasminogen (Plg) using surface receptors like glyceraldehyde-3-phosphate dehydrogenase (GAPDH) to degrade host extracellular matrix (ECM) for infection.
  • Host inflammatory responses require leukocyte migration, facilitated by proteolytic remodeling of ECM via Plg, which depends on phagocyte surface receptors.

Purpose of the Study:

  • To investigate the role of mammalian GAPDH in facilitating phagocyte migration during inflammation.
  • To determine if GAPDH functions as a Plg receptor on macrophages.

Main Methods:

  • Biochemical assays
  • Cellular assays
  • Gene knockdown studies
  • In vivo experiments

Main Results:

  • Macrophages recruit GAPDH to their surface during inflammation.
  • Surface-bound GAPDH captures Plg to promote ECM digestion.
  • This process aids rapid phagocyte migration to inflammatory sites.

Conclusions:

  • GAPDH is an evolutionarily conserved Plg receptor on mammalian cells.
  • GAPDH plays a crucial role in Plg-dependent macrophage recruitment during inflammatory responses to microbial aggression.
  • This presents a scenario where prokaryotic and mammalian GAPDH engage in a conserved function of Plg activation for conflicting outcomes.

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