Detection of post-translational sulfation of alpha-5 beta-1 integrin and its role in integrin-fibronectin binding.
Fibronectins are glycoproteins of the extracellular matrix composed of two 220-kDa polypeptide chains named A and B bound by two disulfide bridges. Both chains when digested with proteolytic enzymes give rise to six different domains named I to VI that are involved in the ligand properties of this molecule. Fibronectins bind fibrin, collagen, glycosaminoglycan residues and several integrins. In this study, using metabolic radiolabeling of alpha 5 beta 1 integrin with sodium sulfate, an immunoprecipitation reaction, inhibition of sulfate incorporation and a fibronectin-binding assay, we were able to detect this integrin as a sulfated molecule and this sulfation appears to regulate the integrin-fibronectin binding.
Veiga
S S
SS
Instituto Ludwig de Pesquisas sobre o Cancer, São Paulo, Brasil.
Elias
M C
MC
Gremski
W
W
Porcionatto
M A
MA
Nader
H B
HB
Brentani
R R
RR
D003094:Collagen / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism; D005337:Fibrin / Q000378:metabolism; D005353:Fibronectins / Q000502:physiology*; D011499:Protein Processing, Post-Translational; D017469:Receptors, Fibronectin / Q000378:metabolism*; D013431:Sulfates / Q000378:metabolism
D005353:Fibronectins; D017469:Receptors, Fibronectin; D013431:Sulfates; D005337:Fibrin; D003094:Collagen