Proteomic analysis of fibrillin-rich microfibrils.
MS has been used to investigate the composition of fibrillin-rich microfibrils from non-elastic and elastic tissues, and to compare fibrillin-1 tryptic fingerprints derived from whole zonules, microfibrils and recombinant fibrillin-1. In all microfibril preparations, fibrillin-1 was abundant and the only fibrillin isoform. MAGP-1 was the only other microfibril-associated molecule. gamma-Crystallin co-purified with zonular microfibrils, so this association may contribute to ciliary zonule anchorage to lens. Recombinant fibrillin-1 tryptic peptides mapped throughout the molecule and included virtually all predicted peptides except for those larger than 4.5 kDa, smaller than 600 Da or post-translationally modified. In contrast, fewer microfibril tryptic fibrillin-1 peptides were detected, although they were derived from domains throughout the molecule and included two peptides after the C-terminal furin processing site. Several microfibril-derived N- and C-terminal domains never yielded any peptides, while tryptic peptides from other domains yielded numerous peptides, suggesting that some tissue microfibril features are retained after trypsinisation. This first MS analysis of a purified extracellular matrix assembly has provided new insights into microfibril composition and fibrillin-1 organisation within them.
Cain
Stuart A
SA
Wellcome Trust Centre for Cell-Matrix Research, Manchester, UK.
Morgan
Amanda
A
Sherratt
Michael J
MJ
Ball
Stephen G
SG
Shuttleworth
C Adrian
CA
Kielty
Cay M
CM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D000071838:Fibrillin-1; D000071837:Fibrillins; D006801:Humans; D013058:Mass Spectrometry; D020894:Microfibrils / Q000737:chemistry*; D008840:Microfilament Proteins / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D008875:Middle Aged; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D020543:Proteome; D011994:Recombinant Proteins / Q000737:chemistry; D054392:Adipokines
D000071838:Fibrillin-1; D000071837:Fibrillins; D008840:Microfilament Proteins; D020543:Proteome; D011994:Recombinant Proteins; C000605722:FBN1 protein, human; D054392:Adipokines