Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.4.21.4 (
trypsin
)
42,187
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
GPI-80
is a glycosylphosphatidylinositol (GPI)-anchored protein that is mainly expressed in human neutrophils. Previous studies using 3H9, a monoclonal antibody (mAb) against
GPI-80
, suggested that
GPI-80
regulates leukocyte adherence and migration through Mac-1.
GPI-80
, which is anchored at the plasma membrane in resting neutrophils, moves into the pseudopodia and is released from activated human neutrophils. Here, we demonstrate that neutrophil activation affects
GPI-80
dynamics using a new anti-
GPI-80
mAb, designated 4D4, which is directed against the form of
GPI-80
found on resting human neutrophils. Similar to 3H9, 4D4 influences Mac-1-dependent neutrophil adhesion. Treatment of purified
GPI-80
with periodic acid and
trypsin
indicated that 3H9 and 4D4 recognize peptide and carbohydrate moieties, respectively. Stimulation with fMLP decreased the binding of 4D4 to
GPI-80
on the neutrophil surface but increased the overall expression of
GPI-80
, as visualized by the 3H9 signal. Confocal laser microscopy revealed the 4D4 signal mainly on cell bodies and at a low level on pseudopodia during migration toward increasing concentrations of fMLP, whereas the 3H9 signal was observed in both areas. In addition, soluble
GPI-80
released from activated neutrophils did not bind 4D4. These results suggest that there are two populations of
GPI-80
that differ in the ability to bind 4D4. The 4D4-recognized form may regulate Mac-1-dependent neutrophil adhesion, and may subsequently be converted to a 4D4-unrecognized form during neutrophil activation.
...
PMID:Structural divergence of GPI-80 in activated human neutrophils. 1754 84
