PRAM-1 is required for optimal integrin-dependent neutrophil function

Mol Cell Biol. 2004 Dec;24(24):10923-32. doi: 10.1128/MCB.24.24.10923-10932.2004.

Abstract

PML-retinoic acid receptor alpha (RARalpha) regulated adaptor molecule 1 (PRAM-1) is an intracellular adaptor molecule that is upregulated during the induced granulocytic differentiation of promyelocytic leukemic cells and during normal human myelopoiesis. This report describes the generation of PRAM-1-deficient mice and an analysis of the function of this adaptor in neutrophil differentiation and mature neutrophil function. We demonstrate here that neutrophil differentiation is not impaired in PRAM-1-deficient mice and that PRAM-1-deficient neutrophils function normally following engagement of Fcgamma receptors. In contrast, mature PRAM-1-null neutrophils exhibit significant defects in adhesion-dependent reactive oxygen intermediate production and degranulation. Surprisingly, other integrin-dependent responses, such as cell spreading and activation of several signaling pathways, are normal. Together, these findings demonstrate the uncoupling of key integrin-dependent responses in the absence of PRAM-1 and show this adaptor to be critical for select integrin functions in neutrophils.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Amino Acid Sequence
  • Animals
  • Calcium / metabolism
  • Cell Degranulation
  • Gene Expression
  • Gene Targeting
  • Humans
  • Integrins / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Molecular Sequence Data
  • Neutrophils / cytology
  • Neutrophils / immunology
  • Neutrophils / metabolism*
  • Opsonin Proteins
  • Phagocytosis
  • Precipitin Tests
  • Protein Structure, Tertiary
  • Proteins / chemistry
  • Proteins / genetics
  • Proteins / metabolism*
  • Respiratory Burst / immunology
  • Sequence Homology, Amino Acid
  • Staphylococcus aureus

Substances

  • Adaptor Proteins, Signal Transducing
  • Integrins
  • Opsonin Proteins
  • PRAM1 protein, human
  • Proteins
  • Calcium