Table 3 Comparison between relevant PPRSV-related and pig proteins identified in other studies and the discriminatory peaks found in this study

PRRSV proteins

- Calculated molecular mass from amino acid sequence [23, 24]

ORF1a – non structural polyprotein

260 - 270

- Calculated molecular mass from amino acid sequence [23, 24]

ORF1ab – non structural polyprotein

420 - 430

- Estimated size from amino acid sequence [25]

ORF2a - glycoprotein 2a (GP2a)

28.4

- 2-DE PAGE and MALDI-TOF [26]

29.4

- SDS page and western of MARC-145 cells infected with PRRSV [27]

ORF2b - non-glycosylated protein 2b

10

10.041 (up-regulated)

- Estimated size from amino acid sequence [25]

ORF3 - glycoprotein 3 (GP3)

30.6

- 2-DE PAGE and MALDI-TOF [26]

29

- Estimated size from amino acid sequence [25]

ORF4 - glycoprotein 4 (GP4)

20

19.761 (up-regulated)

- 2-DE PAGE and MALDI-TOF [26]

19.5

19.761 (up-regulated)

- Estimated size from amino acid sequence [25]

ORF5 - glycoprotein 5 (GP5, E)

22.4

- 2-DE PAGE and MALDI-TOF [26]

22.4

- Estimated size from amino acid sequence [25]

ORF6 - matrix protein (M)

18.9

- 2-DE PAGE and MALDI-TOF [26]

19

- Estimated size from amino acid sequence [25]

ORF7 - nucleocapsid protein (N)

13.8

13.785 (up-regulated)

- 2-DE PAGE and MALDI-TOF [26]

13.5

13.785 (up-regulated)

Pig protein peaks related to PRRSV infection

- MALDI-TOF (sera of pigs after few days of infection with PRRSV vs. normal) [28]

Alpha 1 S (a1S)-subunit of porcine Haptoglobin (Hp)

9.244

Up-regulated in PRRSV infected sera (after 1–7 days)

9.136 (up-regulated)

Unknown peak

4.165

No difference

4.161 (up-regulated)

Unknown peak

4.460

No difference

4.458; 4.462 (both up-regulated)

Unknown peak

5.560

No difference

5.536 (down-regulated)

Unknown peak

8.330

No difference

8.328 (up-regulated)

Unknown peak

8.825

No difference

8.843 (up-regulated)

Unknown peak

12.250/12.55

No difference

12.237/12.522 (both up-regulated)

Unknown peak

14.010

No difference

13.785 (up-regulated)

- 2-DE PAGE and MALDI-TOF of cellular proteins incorporated in PRRSV virions [26]

Keratin 10

58.8

Coronin, actin binding protein, 1B

55.7

Keratin 9

62

Tubulin, beta polypeptide

47.7

Tubulin, alpha, ubiquitous

50.1

Beta-actin

41.7

Actin, gamma 1 propeptide

41.8

Keratin 1

66

Tropomyosin 1 alpha chain isoform 4

32.9

Cofilin 1 (non-muscle)

18.5

Heat shock 70 kDa protein 8 isoform 1

70.8

Heat shock 60 kDa protein 1

61

Ribosomal protein P0

34.2

Heat shock protein 27

22.3

Transketolase

67.8

Pyruvate kinase

57.8

Phosphoglycerate dehydrogenase

56.6

Aldehyde dehydrogenase 1A1

54.8

UDP-glucose dehydrogenase

55

Enolase 1

47.1

Phosphoglycerate kinase 1A isoform 2

44.6

Glyceraldehyde-3-phosphate dehydrogenase

23.8

23.496 (up-regulated)

Guanine nucleotide binding protein (G protein), beta polypeptide 1

37.3

L-lactate dehydrogenase B

36.6

Chain A, Fidarestat Bound To Human Aldose Reductase

35.7

PREDICTED: lactate dehydrogenase

36.6

Peroxiredoxin 1

22.1

Proteasome activator hPA28 subunit beta

27.3

27.606 (down-regulated)

Triosephosphate isomerase 1

26.6

Chaperonin containing TCP1, subunit 3 (gamma)

60.4

Chaperonin containing TCP1, subunit 6A (zeta 1)

58

Chaperonin containing TCP1, subunit 5 (epsilon) protein

59.6

Chaperonin containing TCP1, subunit 2

57.4

PRP19/PSO4 pre-mRNA processing factor 19 homolog

55.1

Retinoblastoma binding protein 4 isoform a

47.6

Eukaryotic translation initiation factor 4A isoform 1

46.1

Proliferating cell nuclear antigen

28.7

Alpha2-HS glycoprotein

35.6

Annexin A2

38.5

Annexin A5

35.9

Annexin A4

36.1

S100 calcium binding protein A10

11.2

11.090 (up-regulated)

Galectin-1

14.7

14.843 (down-regulated)

T-complex protein 1 isoform a

60.3

Gastric-associated differentially expressed protein YA61P

14.9

14.843 (down-regulated)

- 2-DE PAGE and MALDI-TOF of PAM infected with PRRSV vs. normal [29]

Lymphocyte cytosolic protein 1

70

Up-regulated in infected PAM

65 kDa macrophage protein

70.2

Up-regulated

L plastin isoform 2

41.4

Up-regulated

Enolase 1

47.1

Up-regulated

BUB3 budding uninhibited by benzimidazoles 3 isoform a

37.1

Up-regulated

Heat shock 27 kDa protein 1

22.9

Up-regulated

23.162 (up-regulated)

Proteasome beta 2 subunit

22.8

Up-regulated

Transgelin 2

21.1

Up-regulated

NADP-dependent isocitrate dehydrogenase

46.7

Up-regulated

Superoxide dismutase 2

11.7

Up-regulated

11.613 (up-regulated)

Lamin C

65.1

Up-regulated

Aconitase

98.1

Up-regulated

Long chain acyl-CoA dehydrogenase

47.9

Up-regulated

Proteasome subunit alpha type 1

29.5

Up-regulated

70 kDa heat shock cognate protein atpase domain

41.9

Up-regulated

Similar to dihydrolipoamide S-succinyltransferase (E2 component of 2-oxo-glutarate complex)

48.9

Up-regulated

Similar to cleavage stimulation factor, 3 pre-RNA, subunit 1 isoform 3

47.3

Up-regulated

Beta Actin

39.2

Down-regulated in infected PAM

Beta Actin

32.1

Down-regulated

Myoglobin

16.9

Down-regulated

17.171 (up-regulated)

Vacuolar protein sorting 29

20.5

Down-regulated

20.322 (up-regulated)

Transketolase

67.9

Down-regulated

Eukaryotic translation initiation factor 3, subunit 5

37

Down-regulated

Cathepsin D protein

42.7

Down-regulated

Similar to lymphocyte-specific protein 1

40.9

Down-regulated

- 2-DE PAGE and MALDI-TOF of PAM constitutively expressing the PRRSVN protein vs. normal [30]

Proteasome subunit alpha type 6

28.5

Up-regulated in PAM expressing PRRSVN

Heat shock protein 27 kDa

23

Up-regulated

23.162 (up-regulated)

Annexin 1

38.5

Up-regulated

Septin 2

42.9

Up-regulated

Spermidine synthase

34.4

Down-regulated in PAM expressing PRRSVN

Major vault protein

19.3

Down-regulated

Ferritin L subunit

18.3

Down-regulated

Nucleoside diphosphate kinase A

17.3

Down-regulated

17.218 (up-regulated)

Chaperonin containing TCP-1 beta subunit

57.8

Down-regulated

Dihydropyrimidinase related protein 2

62.7

Down-regulated

Translation elongation factor 2

47.2

Down-regulated

- 2-DE PAGE and MALDI-TOF of PAM and Marc-145 cells infected with PRRSV [31]

Cofilin 1

25.773

Up-regulated in Marc-145

Actin-related protein

16.278

Up-regulated in PAM

Vimentin

30.826

Up-regulated in PAM

Alpha cardiac actin

16.758

Up-regulated in PAM

Cofilin 1

18.507

Up-regulated in PAM

Stress 70 protein

55.119

Up-regulated in Marc-145

Peroxiredoxin 2

19.418

Up-regulated in Marc-145

Heat shock 27 kDa protein 1

22.927

Up-regulated in Marc-145

23.162 (up-regulated)

Peroxiredoxin 6

24.995

Up-regulated in Marc-145

Heat shock protein beta 1 (HSPB1)

22.768

Up-regulated in PAM

Ubiquitin

8.559

Up-regulated in Marc-145

8.552 (up-regulated)

Cystatin B (CSTB)

25.288

Up-regulated in PAM

FYVE finger containing phosphoinositide kinase

232.904

Up-regulated in PAM

Pyruvate kinase isozymes M1/M2 (PKM2)

57.744

Up-regulated in PAM

UPF 0681 protein KIAA1033

136.330

Up-regulated in Marc-145

Tropomyosin alpha 4 chain (TPM4)

28.504

Up-regulated in PAM

UPF 0568 protein

28.191

Up-regulated in PAM

LIM and SH3 protein 1

29.975

Down-regulated in Marc-145

Plectin 1

532.578

Down-regulated in Marc-145

Glial fibrillary acidic protein (GFAP)

46.497

Down-regulated in Marc-145

Plectin 1

516.572

Down-regulated in PAM

Galectin 1

14.736

Down-regulated in Marc-145

14.843 (down-regulated)

Galectin 1

14.590

Down-regulated in PAM

Superoxide dismutase 1 (SOD1)

15.236

Down-regulated in PAM

Prohibitin

29.757

Down-regulated in Marc-145

Epidermal fatty acid-binding protein 5 (FABP5)

15.199

Down-regulated in PAM

A kinase anchoring protein AKAP350

416.855

Down-regulated in PAM

Pyridoxine 5 phosphate oxidase variant

29.896

Down-regulated in PAM