Table 2. Cytosolic fraction proteins of Hep G2 and SK-Hep–1 cells were identified by MALDI-TOF.
| Cells | Spot NO. | Accession NO. | Identification | Theoretical M.W./ PI | Score (Seq Cov) | Cellular localization | Molecular function | Class. |
| HepG2 | ||||||||
| 1 | NP 00067 | Mn SOD | 22.304/6.86 | 105(64%) | Mitochondrion | Antioxidant activity | h | |
| 2 | NP 859048 | Peroxiredoxin I | 14.054/6.25 | 85(73%) | Mitochondrion | Antioxidant activity | h | |
| 3 | ND | |||||||
| 4 | P32119 | Peroxiredoxin II | 21.918/5.67 | 106(62%) | Cytoplasm | Antioxidant activity | h | |
| 5 | P27797 | Calreticulin variant | 47.061/4.30 | 181(60%) | ER | Protein folding | i | |
| 6 | P27797 | Calreticulin variant | 47.061/4.30 | 248(67%) | ER | Protein folding | i | |
| 7 | P27797 | Calreticulin variant | 47.061/4.30 | 182(54%) | ER | Protein folding | i | |
| 8 | P06753 | Tropomyosin | 27.387/4.71 | 156(52%) | Cytoplasm | Cytoskeleton, regulation of muscle contraction | c, l | |
| 9 | P12004 | PCNA | 29.092/4.57 | 91(63%) | Nucleus | Cell cycle regulation | a, d | |
| 10 | P06748 | Nucleophosmin, B23 | 31.090/4.71 | 68(40%) | Nucleus | Regulate cell proliferation | a | |
| 11 | P52895 | 3-α-hydroxysteroid/ dihydrodiol dehydrogenase | 37.221/8.02 | 114(66%) | Cytoplasm | Steroid metabolism | g | |
| 12 | P09525 | Annexin A4 | 35.957/5.85 | 151(67%) | Mitochondrion | Calcium binding protein | e, f, l | |
| 13 | P30041 | Peroxiredoxin VI | 25.002/6.02 | 92(61%) | Cytoplasm | Antioxidant activity | h | |
| 14 | P04792 | HSP 27 | 22.427/7.83 | 99(63%) | Nucleus/ Cytoplasm | Protein folding | b | |
| 15 | P60174 | Triosephosphate isomerase (TIM) | 26.807/6.51 | 169(79%) | Cytoplasm | Metabolic enzyme (Glycolysis) | g | |
| Cells | Spot NO. | Accession NO. | Identification | Theoretical M.W./ PI | Score (Seq Cov) | Cellular localization | Molecular function | Class. |
| HepG2 | 16 | P18669 | Phosphoglycerate mutase 1 | 28.769/6.75 | 153(79%) | Cytoplasm | Metabolic enzyme (Glycolysis) | g |
| 17 | P42330 | Aldo keto reductase | 36.226/7.12 | 115(67%) | Cytoplasm | Aldehyde metabolism | g | |
| 18 | NP 002037 | Glucose 3 phosphate dehydrogenase | 36.202/8.26 | 112(64%) | Cytoplasm | Metabolic enzyme (Glycolysis) | g | |
| 19 | P52895 | 3-α-hydroxysteroid/ dihydrodiol dehydrogenase | 37.221/8.02 | 114(66%) | Cytoplasm | Steroid metabolism | g | |
| 20 | NP 005887 | Isocitrate dehydrogenase | 46.944/6.34 | 147(72%) | Mitochondrial matrix | Metabolic enzyme (TCA cycle) | g | |
| 21 | P06733 | α-enolase | 47.35/6.99 | 288(73%) | Cytoplasm | Metabolic enzyme (Glycolysis) | g | |
| 22 | P05783 | Cytokeratin 18 | 47.305/5.27 | 268(69%) | Cytoplasm | Cytoskeleton | c | |
| 23 | NP 003290 | Tumor rejection antigen, gp96 | 92.567/4.77 | 244(55%) | Cytoplasm | Protein folding and transport | h | |
| 24 | P19338 | Nucleolin | 58.576/4.57 | 96(32%) | Nucleus | DNA/ RNA binding | d | |
| 25 | NP 003290 | Tumor rejection antigen, gp96 | 92.567/4.77 | 244(55%) | Cytoplasm | Protein folding and transport | h | |
| Cells | Spot NO. | Accession NO. | Identification | Theoretical M.W./ PI | Score (Seq Cov) | Cellular localization | Molecular function | Class. |
| HepG2 | 26 | P38646 | Grp 75 | 74.019/5.97 | 271(58%) | Mitochondrion | Cell proliferation and Cellular aging | d |
| 27 | NP 004125 | HSP 70k 9B (mortalin–2) | 74.093/6.04 | 268(58%) | Cytoplasm | Anti-apoptosis, protein folding | b | |
| 28 | NP 003350 | UDP-glucose dehydrogenase | 55.674/6.73 | 298(75%) | Cytoplasm | Metablolic enzyme (Glycosaminoglycan biosynthesis) | g | |
| 29 | P00352 | Retinal dehydrogenase (AL1A1) | 55.323/6.29 | 112(53%) | Cytoplasm | Metabolic enzyme (retinoic acid biosynthesis) | g | |
| 30 | P60709 | β-actin | 42.08/5.37 | 87(66%) | Cytoskeleton | Cytoskeleton | c, l | |
| 31 | NP 001606 | gamma-actin | 42.108/5.31 | 165(77%) | Cytoplasm | Cytoskeleton, cell motility | c, l | |
| 32 | NP 00684 | Protein disulfide-isomerase (ER 60) | 57.146/5.98 | 301(67%) | ER lumen | Folding of proteins containing disulfide bonds in ER | h, i | |
| 33 | P10809 | Chaperonin GroEL procursor | 61.187/5.70 | 162(57%) | Mitochondrial matrix | Transport the mitochondrial proteins | b, k | |
| 34 | P11021 | Grp 78 | 72.407/5.07 | 188(55%) | ER lumen | Protein folding in ER | k | |
| 35 | P31939 | Bifunctional purine biosynthesis protein, PURH | 64.938/6.39 | 268(74%) | Nucleus/ cytoplasm | Nucleic acid metabolism | g | |
| Cells | Spot NO. | Accession NO. | Identification | Theoretical M.W./ PI | Score (Seq Cov) | Cellular localization | Molecular function | Class. |
| SK-Hep–1 | ||||||||
| 36 | P04406 | Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) | 36.202/8.26 | 112(64%) | Cytoplasm | Metabolic enzyme (Glycolysis) | g | |
| 37 | P56876 | Probable thioredoxin peroxidase (PAGA) | 22.324/8.27 | 165(71%) | Nucleus/ cytoplasm | Antioxidant enzyme | h | |
| 38 | P63104 | 14.3.3 protein zeta/delta | 30.10/4.72 | 149(58%) | Cytoplasm | Signal transduction | j | |
| 39 | P31947 | 14.3.3 protein sigma (Stratifin) | 27.871/4.68 | 96(44%) | Cytoplasm | Cell proliferation, signal transduction | a, d, j | |
| 40 | P06753 | Tropomyosin | 27.387/4.71 | 120(50%) | Cytoplasm | Cytoskeleton, regulation of muscle contraction | c, l | |
| 41 | P07951 | Tropomyosin | 32.856/4.72 | 98(52%) | Cytoplasm | Cytoskeleton, regulation of muscle contraction | c, l | |
| 42 | P62258 | 14.3.3 protein epsilon | 29.326/4.63 | 137(66%) | Cytoplasm | Signal transduction | j | |
| 43 | P12004 | PCNA | 29.092/4.57 | 91(63%) | Nucleus | Cell cycle regulation | a, d | |
| 44 | BAA82513 | Pre-mRNA splicing factor SP2p32 | 31.287/4.74 | 73(61%) | Cytoplasm | mRNA processing | d | |
| 45 | P06748 | B23 | 31.090/4.71 | 82(43%) | Nucleus | Regulate cell proliferation | a | |
| 46 | P08670 | Vimentin | 53.545/5.06 | 283(72%) | Cytoskeleton | Cytoskeleton, cell motility | c, f, l | |
| 47 | P08670 | Vimentin | 53.545/5.06 | 306(71%) | Cytoskeleton | Cytoskeleton, cell motility | c, f, l | |
| 48 | P08670 | Vimentin | 53.464/4.99 | 281(80%) | Cytoskeleton | Cytoskeleton, cell motility | c, f, l | |
| 49 | NP 002264 | Keratin 8 | 30.802/5.02 | 177(83%) | Intermediate filament | Cytoskeleton organization and biogenesis | c | |
| Cells | Spot NO. | Accession NO. | Identification | Theoretical M.W./ PI | Score (Seq Cov) | Cellular localization | Molecular function | Class. |
| SK-Hep–1 | 50 | P10809 | Chaperonin GroEL procursor | 61.187/5.70 | 162(57%) | Mitochondrial matrix | Transport the mitochondrial proteins | b, k |
| 51 | NP 00684 | Protein disulfide-isomerase | 57.480/4.76 | 267(69%) | ER lumen | Folding of proteins containing disulfide bonds in ER | h, i |
ND: None detected.
The functional classification (Class) of identified proteins is shown a ~ m. a: cell cycle; b: chaperone/ stress response; c: cytoskeleton/ cell mobility; d: DNA replication/ gene regulation/ cell proliferation; e: ion channels; f: membrane proteins; g: metabolic enzyme; h: protection and detoxification; i: protein synthesis and degradation; j: signal transduction; k: transport/ binding proteins; l: intermediate filaments; m: unannotated/ function inferred.