Structural and functional analysis of the N-terminal extracellular region of beta-dystroglycan.
A protein fragment corresponding to the mouse beta-dystroglycan N-terminal extracellular region from position 654 to 750, beta-DG(654-750) was recombinantly expressed in BL21(DE3) Escherichia coli cells. Secondary structure prediction of the protein fragment reveals about 70% of random coil, as confirmed by circular dichroism analysis. Moreover, fluorescence analysis shows that the tryptophan residue in position 659 lays in a solvent-exposed fashion. These data suggest that the beta-DG(654-750) is likely to have a quite flexible structure and to be only partially folded. Interestingly, the protein still retains its biological function since using solid-phase assays we have detected binding of biotinylated beta-DG(654-750) both to native alpha-dystroglycan and to a recombinant fragment which spans the C-terminal region of alpha-dystroglycan.
Di Stasio
E
E
Centro Chimica dei Recettori (CNR), Istituto di Chimica e Chimica Clinica, Università Cattolica del Sacro Cuore, L.go F. Vito 1, Rome, 00168, Italy.
Sciandra
F
F
Maras
B
B
Di Tommaso
F
F
Petrucci
T C
TC
Giardina
B
B
Brancaccio
A
A
D000595:Amino Acid Sequence; D000818:Animals; D019921:Biotinylation; D002942:Circular Dichroism; D003598:Cytoskeletal Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004220:Disulfides / Q000737:chemistry / Q000378:metabolism; D049030:Dystroglycans; D004926:Escherichia coli / Q000235:genetics; D006031:Glycosylation; D008024:Ligands; D008562:Membrane Glycoproteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D011485:Protein Binding; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D013329:Structure-Activity Relationship; D014364:Tryptophan / Q000737:chemistry / Q000378:metabolism
D003598:Cytoskeletal Proteins; D004220:Disulfides; D008024:Ligands; D008562:Membrane Glycoproteins; D010446:Peptide Fragments; D011994:Recombinant Proteins; D049030:Dystroglycans; D014364:Tryptophan