Table 1. U937 monocyte lipid body-associated proteins identified by MS/LS.
| Location or function TM: predicted membrane insertion |
Band no. | Protein name | M.W. (kDa) | Accession ID in Swiss-Prot database | Found with LBs in mammalian cells | Ref. |
|---|---|---|---|---|---|---|
| Related to lipid bodies | ||||||
| 2 | Adipophilin (ADRP) | 48.0 | Q99541 | yes | (6, 10–14) | |
| 2 | TIP47 (mannose-6-phosphate receptor binding protein) | 47.0 | O60664 | yes | (11–14, 63, 64) | |
| TM1:281–309 | 2 | CGI-49 (saccharopine dehydrogenase) | 46.9 | Q9Y363 | yes | (12–14) |
| TM2: 309–385 | ||||||
| TM:77–95 | 4 | CGI-58 | 38.8 | Q9Y369 | yes | (10, 11, 65, 66) |
| Lipid metabolism | ||||||
| TM: 1810–1833 | 1 | Acetyl CoA carboxylase | 265 | Q13085 | yes | (10, 11) |
| TM: 95–123 | 1 | Lanosterol synthase | 83.3 | P48449 | yes | (6, 10–14) |
| TM1: 16–44 | 1 | Long chain fatty acid CoA synthase 3 | 80.3 | O95573 | yes | (6, 10–12, 14) |
| TM2: 172–190 | ||||||
| TM1: 19–44 | 2 | Squalene epoxidasea | 63.9 | Q14534 | yes | (10, 11) |
| TM2: 54–82 | ||||||
| TM3:125–147 | ||||||
| TM4: 513–533 | ||||||
| TM5: 546–566 | ||||||
| 2 | RIKEN cDNA 0610039C21, Triglyceride lipase | 47.4 | AK002826 (nucleotide sequence) | yes | (67, 68) | |
| TM: 296–324 | 3 | NAD(P)H-dependent steroid dehydrogenase | 41.9 | Q15738 | yes | (11–14, 69, 70) |
| TM1: 86–112 | 4 | 17-β-hydroxysteroid dehydrogenase 7 | 38.2 | P56937 | yes | (10–12, 14) |
| TM2: 230–258 | ||||||
| TM: 1355–1379 | 4 | Retinal short chain dehydrogenase, ret SDR1 | 33.5 | AF061741 | yes | SDR families (10–12, 14) |
| TM1: 13–33 | 4 | Retinal short chain dehydrogenase, ret SDR2 | 32.9 | Q8TDV9 | yes | SDR families (10–14) |
| TM2: 44–64 | ||||||
| TM3: 192–208 | ||||||
| TM4: 267–295 | ||||||
| Cytoskeleton protein | ||||||
| TM:127–155 | 2 | Tubulin-α | 50.0 | Q13748 | yes | (10, 14) |
| 3,4 | Actin | 41.7 | P02570 | yes | (11, 71) | |
| Endoplasmic reticulum proteins/glycosylation | ||||||
| TM1:4–25, TM2:408–433 | 2 | Oligosaccharyl transferase subunita | 48.0 | P39656 | — | |
| TM: 60–85 | 4 | Dehydrodolichyl diphosphate synthase | 38.7 | Q86SQ9 | — | |
| TM1: 8–36, | 4 | Dolichyl-phosphate-glucosyltransferase | 36.9 | Q9Y673 | yes | (10) |
| TM2: 207–232, | ||||||
| TM3: 259–278 | ||||||
| TM: 4–26 | 4 | NADH-cytochrome b5 reductase | 34.1 | P00387 | yes | (11–13) |
| Chaperones/folding enzymes | ||||||
| 1 | Heat shock protein 70 | 75 | P38646 | yes | (11, 14, 72) | |
| 1 | BiP (glucose regulated-protein 78) | 72.3 | P11021 | yes | (10, 11, 13, 14, 73) | |
| TM1: 3–20 | 1 | Calnexin | 67.6 | P27824 | yes | (13, 14, 73) |
| TM2: 479–503 | ||||||
| TM:4–21 | 2 | Protein disulfide isomerase P5 | 48.1 | Q15084 | yes | PDI family (10, 11, 13) |
| TM: 4–21 | 5 | Cyclophilin B | 22.7 | P23284 | — | |
| Ribosome/translation proteins | ||||||
| TM: 98–124 | 2 | Eukaryotic elongation factor 1-α | 50 | P04720 | — | |
| 2 | Eukaryotic elongation factor 1-γ | 50 | P26641 | — | ||
| 2 | Eukaryotic initiation factor 4A-1 | 46.2 | P04765 | — | ||
| TM:117–145 | 5 | 60S ribosomal protein L11a | 20.1 | P39026 | — | |
| 6 | 60S ribosomal protein L23a | 14.9 | P23131 | — | ||
| 6 | 40S ribosomal protein S20a | 13.4 | P17075 | — | ||
| TM: 41–61 | 6 | 60S acidic ribosomal proteina | 11.5 | P05386 | — | |
| Vesicular trafficking | ||||||
| TM1: 162–184 | 3 | VAT-1 (synaptic vesicle membrane protein) homolog | 32.6 | Q99536 | — | |
| TM2: 190–206 | ||||||
| 4 | SNAP29, vesicle-membrane fusion protein | 29 | Q95721 | yes | SNAP family (10) | |
| TM1: 9–37 | 5 | Transmembrane traffic protein | 25 | P49755 | — | |
| TM2: 184–210 | ||||||
| 5 | Rab 1A (Ras-related protein) | 22.7 | P11476 | yes | (10, 13) | |
| 5 | Rab 1B | 22.2 | Q9H0U4 | yes | (10, 11, 13) | |
| 5 | Rab 7 | 23.5 | P51149 | yes | (10, 11, 13, 14) | |
| 5 | Rab 10 | 22.5 | Q88386 | yes | (10, 11, 13) | |
| TM: 71–99 | 5 | Rab 11 | 24.4 | P24410 | yes | (10, 13) |
| TM: 12–37 | 5 | Rab 14 | 23.9 | P35287 | yes | (10, 14) |
| 5 | Rab 18 | 23 | Q9NP72 | yes | (10, 11, 13–15, 44) | |
| 5 | GTP-binding protein SAR 1a | 22.4 | Q9NR31 | — | ||
| 5 | Rap-1a | 21 | P10113 | yes | Rap-1b(12) | |
| Nuclear proteins | ||||||
| 2 | BAT-1 (HLA-B associated transcript 1) | 49.0 | Q13838 | — | ||
| TM: 56–76 | 4 | HnRNP E1a | 37.5 | Q15365 | — | |
| 4 | HnRNP C1/C2a | 33.7 | P07910 | — | ||
| TM:222–246 | 5 | Emerin | 29.0 | P50402 | — | |
| TM: 46–66 | 6 | Histone 2Az | 13.4 | P17317 | — | |
| 6 | Histone 2Bb | 13.8 | P58876 | — | ||
| 6 | Histone 4 | 11.2 | P02304 | — | ||
| Serum proteins | ||||||
| TM1: 1–24 | 1 | Albumin | 69.3 | P02768 | yes | (72) |
| TM2: 32–56 | ||||||
| TM: 105–133 | 6 | Hemoglobin γ | 16.0 | P02096 | — | |
| 6 | Hemoglobin β | 15.9 | P02023 | — | ||
| TM: 98–116 | 6 | Hemoglobin ζ | 15.5 | P02008 | — | |
| TM: 98–15 | 6 | Hemoglobin α | 15.1 | P69905 | — | |
| Miscellaneous | ||||||
| EF-hand Motif | ||||||
| 5 | Calcium binding protein p22 | 22.3 | Q99653 | yes | (11) | |
| 6 | S100 calcium binding protein A9, Migration inhibitory related protein (MRP)-14 | 13.2 | P06702 | — | ||
| Apoptosis | ||||||
| TM:8–36 | 4 | AMID, P53-responsive gene | 40.5 | Q9BRQ8 | yes | (11, 13) |
| Other | ||||||
| 5 | VDAC-1 (Voltage-dependent anion-selective channel protein-1) | 30.6 | P21796 | yes | (10) | |
| TM1: 16–44 | 2 | AUP-1 (Ancient ubiquitous protein-1) | 53.0 | Q9Y679 | yes | (13, 14) |
| TM2: 149–177 | ||||||
| TM3: 269–288 | ||||||
| TM1: 60–85 | 2 | HSPC028, basic leu zipper and W2 domain 2 | 48.2 | Q9Y6E2 | — | |
| TM2: 151–170 | ||||||
| TM3: 355–383 | ||||||
| 2 | Carboxypeptidase A2 | 46.4 | P48052 | — | ||
| 2 | Polyubiquitin | 25.7 | Q9BWD6 | — | ||
| TM: 178–195 | 4 | Hypothetical protein FLJ21820 | 22.3 | Q9H6V9 | yes | (13) |
| 4 | GAPDH | 37.3 | P04406 | yes | (12) | |
| TM1: 78–96 | 4 | Hypothetical protein MGC10084 gene | 36 | BC015168 | — | |
| TM2: 1288–1308 | ||||||
| TM3: 1323–1343 | ||||||
| TM: 8–36 | 5 | TD 54 | 35 | O43399 | yes | (11, 14) |
a
Only a single matching peptide sequence.