Table 1.
Functional classification of differentially expressed proteins in normal articular cartilage and during early OA in rat identified by 2-DE and MALDI-TOF/MS
| Spot no. a) | Protein name b) | Description | Accession no. b) | Theor M r/ /p I c) | Exp. M r /p I d) | % Seq Cov. e) | Match | Score f) | Proteins expression compared with Normal samples (% increase) g) | ||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Protein | Pept. | ||||||||||
| OA 3 days | OA 5 days | OA 10 days | |||||||||
| Extracellular Matrix | |||||||||||
| S1 | Col2α1 | Collagen alpha-1 (II) chain precursor | P05539 | 38/8.46 | 30-32/6.6-6.7 | 12 | 16 | 84 | 22 | 15 | 12 |
| Transcription, protein synthesis | |||||||||||
| S2 | Eef1α1 | Elongation factor 1-alpha 1 | P62630 | 50.11/9.1 | 50.11/9.1 | 32 | 13 | 37 | 499 | 407 | 314 |
| S3 | DJ-1 | Protein DJ-1 | 88767 | 19.9/6.32 | 19.9/6.3 | 54 | 9 | 85 | 138 | 313 | 271 |
| Glycolysis and energy production | |||||||||||
| S4 | Nme2 | Nucleoside diphosphate kinase | P19804 | 17.28/6.9 | 17.3/6.9 | 87 | 16 | 187 | 127 | 515 | 700 |
| S5 | Pnp | Purine nucleoside phosphorylase | P85973 | 32.3/6.46 | 32.32/6.4-6.5 | 43 | 8 | 49 | 243 | 277 | 384 |
| Signal transduction | |||||||||||
| S6 | CaM | Calmodulin | P62161 | 16.7/4.09 | 16.8/5.47 | 63 | 8 | 101 | 124 | 130 | 185 |
| S7 | Pebp1 | Phosphatidylethanolamine binding protein 1 | P31044 | 20.6/5.48 | 17.18/4.9-5.5 | 52 | 7 | 76 | 54 | 92 | 29 |
| Transport | |||||||||||
| S8 | Alb | Serum albumin (n-terminal fragment) | P02770 | 65.9/5.8 | 68.6/6.09 | 24 | 12 | 105 | 435 | 853 | 568 |
| S9 | Hba1 | Haemoglobin subunit alpha-1/2 | P01946 | 15.1/7.93 | 19.7/6.32 | 69 | 6 | 88 | 231 | 157 | 284 |
| Others | |||||||||||
| S10 | Lxn | Latexin | Q64361 | 25.5/5.77 | 25/5.8 | 48 | 11 | 118 | 20 | 29 | 54 |
a)Spot number as indicated in Figure 2.
b)Protein name and accession number according UniprotKB/Swiss-prot database of Rattus norvegicus species.
c)Theoretical Mr and pI according to protein sequence.
d)Experimental Mr and pI calculated by analysis of the gel image with ImageMaster 2D Platinum 7.0 software.
e)Sequence coverage for identified protein (peptide confidence ≥95) in relation on the full sequence.
f)The Score value listed within the Query table is the Ion Score. Ion score is −10*Log (P), where P is the probability that the observed match is random event.
g)% Relative volume by condition in early OA vs Normal condition (Tukey-Kramer test, p ≤0.001). The percentage of increase of the protein expression is represented by bold numbers.