The heterodimer of the Ca2+-binding proteins MRP8 and MRP14 binds to arachidonic acid.
The S100 proteins MRP8 and MRP14 have been shown to be expressed by myeloid cells during inflammatory reactions. Since the majority of S100 proteins exhibit their biological activity when associated as complex it was investigated whether murine MRP8 and MRP14 form heterodimers and whether this complex may bind lipids of the cell membrane. This is of particular importance since their anchoring into the plasma membrane is unclear although upon calcium binding the proteins translocate from the cytoplasma to the cytoskeleton and the plasma membrane. Using recombinant proteins we could show that not the monomers but only the heterodimers specifically bind arachidonic acid. This finding opens new perspectives for the role of MRP8 and MRP14 in acute and chronic inflammatory processes.
Klempt
M
M
Institute of Experimental Dermatology, University of Münster, Germany.klempt@uni-muenster.de
Melkonyan
H
H
Nacken
W
W
Wiesmann
D
D
Holtkemper
U
U
Sorg
C
C
D000818:Animals; D000943:Antigens, Differentiation / Q000737:chemistry / Q000378:metabolism*; D016718:Arachidonic Acid / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism / Q000494:pharmacology; D002135:Calcium-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D040501:Calgranulin A; D040502:Calgranulin B; D003001:Cloning, Molecular; D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D051379:Mice; D019301:Oleic Acid / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011485:Protein Binding; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D013154:Spleen / Q000737:chemistry
D000943:Antigens, Differentiation; D002135:Calcium-Binding Proteins; D040501:Calgranulin A; D040502:Calgranulin B; D011994:Recombinant Proteins; D016718:Arachidonic Acid; D019301:Oleic Acid; D002118:Calcium