Table 3. Putative mitosomal proteins classified by predicted function: protein modification, cztosceletal and motor proteins.
Accession number | Annotation | Identification | Localization | Structure | ||||||
MASCOT | Coverage | MiD | SignalP | Target P | Psort II | MEMSAT3 | SGP | TMHMM | ||
score | peptides | % mito | TM No. | TM No. | ||||||
Protein modification | ||||||||||
GL50803_8587 | Kinase, AGC NDR | 22 | 1 | Y | N | O | 4% | 0 | # | 0 |
GL50803_14223 | Kinase, NEK | 124 | 2 | Y | N | O | 13% | 0 | # | 0 |
GL50803_16824 | Kinase, NEK | 87 | 2 | Y | N | O | 0 | # | 0 | |
GL50803_17510 | Kinase, NEK | 25 | 1 | Y | N | O | 17% | 0 | # | 0 |
GL50803_5375 | Kinase, NEK | 46 | 1 | Y | N | O | 17% | 0 | # | 0 |
GL50803_11775 | Kinase, NEK-frag | 50 | 2 | Y | N | O | 17% | 0 | # | 0 |
GL50803_7183 | Kinase, NEK-frag | 22 | 1 | Y | N | O | 13% | 0 | # | 0 |
GL50803_8805 | Kinase, SCY1 | 159 | 2 | Y | N | O | 11% | 1 | 0 | |
GL50803_7110 | Ubiquitin | 360 | 5 | Y | N | O | 17% | 0 | # | 0 |
Cytoskeletal and motor proteins | ||||||||||
GL50803_11654 | Alpha-1 giardin | 934 | 17 | Y | N | O | 13% | 1 | 0 | |
GL50803_7796 | Alpha-2 giardin | 478 | 8 | Y | N | O | 17% | 1 | 0 | |
GL50803_5649 | Alpha-10 giardin | 294 | 5 | Y | N | O | 9% | 1 | 0 | |
GL50803_15097 | Alpha-14 giardin | 643 | 9 | Y | N | O | 4% | 0 | # | 0 |
GL50803_112079 | Alpha-tubulin | 394 | 7 | Y | N | O | 0 | # | 0 | |
GL50803_136020 | Beta tubulin | 841 | 13 | Y | N | O | 0 | # | 0 | |
GL50803_42285 | Ciliary dynein heavy chain 11 | 23 | 1 | Y | N | 1 | 0 | |||
GL50803_93736 | Dynein heavy chain | 29 | 1 | Y | N | 13% | 0 | 0 | ||
GL50803_16993 | FtsJ cell division protein, putative | 24 | 1 | Y | N | O | 17% | 0 | # | 0 |
GL50803_102101 | Kinesin-3 | 85 | 1 | Y | N | O | 26% | 0 | # | 0 |
GL50803_21444 | Spindle pole protein, putative | 63 | 2 | Y | N | O | 22% | 0 | # | 0 |
GL50803_8589 | Suppressor of actin 1 | 81 | 2 | Y | N | O | 11% | 3 | 2 |
Mascot score, Mascot total ion score for the identified protein. Coverage, number of unique peptides per identified protein. MiD, mitosomal distribution. Proteins are marked “Y” if their distributions in fractions #3 and #4 of the Optiprep gradient (measured by the iTRAQ ratio) were within the range between Cpn10 and IscU and the window that extended in both directions by half of the distance between these markers. Proteins with ratios outside of this range are indicated with “N”. TargetP and PsortII were used to predict the subcellular location of Giardia proteins. S, secretory; N, non-secretory; M, mitochondrial; O, other. Exp. ver., experimental verification of protein localization using the pONDRA expression vector. The recombinant tagged proteins were localized by fluorescence microscopy. M, mitosome; ER, endoplasmic reticulum; O, other; ? inconclusive. MEMSAT3 and TMHMM were used to predict transmembrane domains. SGP, predicted soluble proteins are marked with number sign (#). Asterisk (*) is used where no data were available. (**) transformed Giardia did not express the recombinant tagged protein.