TABLE 2.
Summary of site-specific modification analysis by mass spectrometry of non-cross-linked, hydroxylated (this table shows Pro hydroxylation), and glycosylated residues in mice tail tendon type I collagen
| Site occupancy |
||||
|---|---|---|---|---|
| WT | Het | KO | ||
| % | % | % | ||
| α1(I) Pro-986 | Pro | 17.9 ± 1.2 | 15.6 ± 0.7 | 83.0 ± 2.7a,b |
| 3-Hyp | 82.1 ± 1.2 | 84.4 ± 0.7 | 17.0 ± 2.7a,b | |
| α1(I) Pro-707 | Pro | 56.8 ± 3.5 | 52.9 ± 2.9 | 55.1 ± 6.1 |
| 3-Hyp | 43.2 ± 3.5 | 47.1 ± 2.9 | 44.9 ± 6.1 | |
| α2(I) Pro-707 | Pro | 23.7 ± 4.9 | 17.9 ± 1.7 | 32.5 ± 8.8b |
| 3-Hyp | 76.3 ± 4.9 | 82.1 ± 1.7 | 67.5 ± 8.8b | |
| α1(I) Lys-87 | Lys | 9.0 ± 0.6 | 3.6 ± 0.3 | 38.5 ± 5.0a,b |
| Hyl | 66.9 ± 2.4 | 68.5 ± 2.3 | 39.1 ± 1.6a,b | |
| G-Hyl | 4.9 ± 1.3 | 6.3 ± 1.0 | 4.0 ± 0.3b | |
| GG-Hyl | 19.2 ± 1.5 | 21.7 ± 1.4 | 18.4 ± 3.4 | |
| α1(I) Lys-174 | Lys | 58.7 ± 0.8 | 59.5 ± 3.0 | 54.1 ± 3.4 |
| Hyl | 37.7 ± 0.7 | 37.2 ± 2.5 | 38.0 ± 3.0 | |
| G-Hyl | 2.0 ± 0.1 | 1.9 ± 0.4 | 4.9 ± 0.4a,b | |
| GG-Hyl | 1.6 ± 0.1 | 1.5 ± 0.2 | 2.9 ± 0.4a,b | |
| α1(I) Lys-219 | Lys | 83.5 ± 1.4 | 82.6 ± 1.1 | 73.8 ± 3.6a,b |
| Hyl | 16.5 ± 1.4 | 17.4 ± 1.1 | 26.2 ± 3.6a,b | |
| α1(I) Lys-603 | Lys | 33.6 ± 0.4 | 34.5 ± 2.1 | 32.9 ± 3.2 |
| Hyl | 66.4 ± 0.4 | 65.5 ± 2.1 | 67.1 ± 3.2 | |
| α2(I) Lys-87 | Lys | 4.4 ± 0.4 | 4.9 ± 0.4 | 44.7 ± 2.1a,b |
| Hyl | 95.6 ± 0.4 | 95.1 ± 0.4 | 55.3 ± 2.1a,b | |
| α2(I) Lys-174 | Lys | 25.5 ± 3.0 | 31.9 ± 7.9 | 80.0 ± 1.2a,b |
| Hyl | 70.7 ± 4.3 | 65.6 ± 6.9 | 16.5 ± 0.9a,b | |
| G-Hyl | 3.4 ± 1.3 | 2.0 ± 0.6 | 1.9 ± 0.4 | |
| GG-Hyl | 0.3 ± 0.1 | 0.5 ± 0.4 | 1.5 ± 0.9 | |
| α2(I) Lys-219 | Lys | 67.0 ± 0.2 | 69.7 ± 3.3 | 55.7 ± 2.5a,b |
| Hyl | 32.2 ± 0.2 | 29.7 ± 3.2 | 41.6 ± 2.6a,b | |
| G-Hyl | 0.4 ± 0.1 | 0.3 ± 0.1 | 1.2 ± 0.2a,b | |
| GG-Hyl | 0.4 ± 0.1 | 0.3 ± 0.0 | 1.5 ± 0.4a,b | |
a p < 0.05 between WT and KO.
b p < 0.05 between Het and KO.