Research Article

Phenotypic and Proteomic Characteristics of Human Dental Pulp Derived Mesenchymal Stem Cells from a Natal, an Exfoliated Deciduous, and an Impacted Third Molar Tooth

Table 3

Classification of the proteins that were identified by MALDI-TOF/TOF analysis. The classifications were made based on PANTHER analysis and Swiss-Prot annotations.

Protein nameFunctionBiological process involved

Apoptosis related
GalectinApoptosis, cell proliferation, and differentiationApoptosis
Cathepsin BThiol protease which is believed to participate in intracellular degradation and turnover of proteins.Regulation of apoptotic process and proteolysis
Cathepsin DAcid protease active in intracellular protein breakdownRegulation of apoptotic process and proteolysis
Histidine triad nucleotide-binding protein 1Hydrolyzes purine nucleotide phosphoramidatesApoptosis

Signal transduction
SA100A6May function as calcium sensor and modulator, contributing to cellular calcium signaling Signal transduction
Protein S100-A11Signal transduction
Annexin A1Calcium/phospholipid-binding protein which promotes membrane fusion and is involved in exocytosisCell surface receptor signaling pathway

Protein biosynthesis and degradation
Ubiquitin Behaves as a molecular tag for degradation of proteinsUbiquitination
Putative 40S ribosomal protein S10-likeRibonucleoproteinProtein biosynthesis
Eukaryotic translation initiation factor 5A-1Ribosome binding 
Translation elongation factor activity
Protein biosynthesis
Ubiquitin carboxyl-terminal hydrolaseProcessing of ubiquitin precursors and of ubiquitinated proteinsUbl conjugation pathway
39S ribosomal protein L12, mitochondrialRibonucleoproteinMitochondrial protein biosynthesis
Proteasome subunit alpha type 1The proteasome is a multicatalytic proteinase complex which is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pHImmunity
Proteasome subunit beta type 7Cleavage of peptide bonds with very broad specificityProtein degradation

Transcription related
Heterogeneous nuclear ribonucleoprotein A/BBinds single-stranded RNA. Has a high affinity for G-rich and U-rich regions of hnRNATranscription, 
transcription regulation
Heterogeneous nuclear ribonucleoprotein D0Binds with high affinity to RNA molecules that contain AU-rich elements (AREs) found within the 3′-UTR of many protooncogenes and cytokine mRNAsTranscription, 
transcription regulation
Heterogeneous nuclear ribonucleoprotein HThis protein is a component of the heterogeneous nuclear ribonucleoprotein (hnRNP) complexes which provide the substrate for the processing events that pre-mRNAs undergo before becoming functional, translatable mRNAs in the cytoplasm. Mediates pre-mRNA alternative splicing regulationMediates pre-mRNA alternative splicing regulation
Heterogeneous nuclear ribonucleoprotein D-likeActs as a transcriptional regulator. Promotes transcription repression.Transcription, 
transcription regulation
Paraspeckle component 1Regulates, cooperatively with NONO and SFPQ, androgen receptor-mediated gene transcription activity in Sertoli cell lineTranscription, 
transcription regulation

Nucleotide metabolism
UMP-CMP kinaseCatalyzes the phosphorylation of pyrimidine nucleoside monophosphates at the expense of ATPNucleotide metabolism
Nucleoside diphosphate kinase AMajor role in the synthesis of nucleoside triphosphates other than ATPNucleotide metabolism

Redox metabolism related
Thioredoxin domain-containing protein 12Possesses significant protein thiol-disulfide oxidase activity Oxidoreductase
Peroxiredoxin-2Involved in redox regulation of the cell. Reduces peroxides with reducing equivalents provided through the thioredoxin systemHydrogen peroxide catabolic process
removal of superoxide radicals
Superoxide dismutase Cu-ZnDestroys radicals which are normally produced within the cells and which are toxic to biological systems.Antioxidant, 
oxidoreductase
Thioredoxin-dependent peroxide reductasePeroxidase activity, 
peroxiredoxin activity
Involved in redox regulation of the cell
Glutathione S-transferase PConjugation of reduced glutathione to a wide number of exogenous and endogenous substratesGlutathione derivative biosynthetic process
Persulfide dioxygenase ETHE1, mitochondrialPlays ab essential role in hydrogen sulfide catabolism in the mitochondrial matrixHydrogen sulfide metabolic process

Protein folding/stress
Tubulin-specific chaperone AInvolves the early step of the tubulin folding pathway.Chaperone binding
UPF0556 protein C19orf10 Involved in unfolded protein response, cellular protein metabolic process
Protein DJ-1Protects cells against oxidative stress and cell death.Oxidative stress
Heat shock protein beta-1Involved in stress resistance and actin organization.Stress response
Heat shock cognate 71 kDa proteinActs as a repressor of transcriptional activationStress response
60 kDa heat shock protein, mitochondrialImplicated in mitochondrial protein import and macromolecular assemblyde novo' protein folding,  
stress response
78 kDa glucose-regulated proteinPlays a role in facilitating the assembly of multimeric protein complexes inside the endoplasmic reticulumER overload response
Peptidyl-prolyl cis-trans isomerase AIt catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides.PPIases accelerate the folding of proteins
Tripeptidyl-peptidase 1Lysosomal serine protease with tripeptidyl-peptidase I activity Involved in unfolded protein response

Energy metabolism
ATP synthase subunit DATP synthesis Energy metabolism
Phosphoglycerate mutase 1Interconversion of 3- and 2-phosphoglycerateGlycolysis, gluconeogenesis
Alpha-enolaseRole in glycolysis, plays a part in various processes such as growth control, hypoxia tolerance, and allergic responses.Glycolysis, 
plasminogen activation 
Transcription, 
transcription regulation
Beta-enolaseStriated muscle development and regeneration.Glycolysis
Gamma-enolaseHas neurotrophic and neuroprotective properties on a broad spectrum of central nervous system (CNS) neuronsGlycolysis
Triosephosphate isomeraseD-Glyceraldehyde 3-phosphate = glycerone phosphate.Energy metabolism

Structural proteins
Coactosin-like proteinActs as a chaperone for ALOX5 (5LO), influencing both its stability and activity in leukotrienes synthesis.Binds to F-actin in a calcium-independent manner
Actin related protein 2/3 complex subunit 5Component of the Arp2/3 complex which is involved in regulation of actin polymerizationStructural constituent of cytoskeleton
Syntenin-1An adapter protein, in adherens junctions may function to couple syndecans to cytoskeletal proteins or signaling componentsActin cytoskeleton organization
Calponin-2Thin filament-associated protein that is implicated in the regulation and modulation of smooth muscle contraActin binding
Actin, cytoplasmic 1Cell motilityCell structure formation
Keratin, type II cytoskeletal 1Regulate the activity of kinases such as PKC and SRC via binding to integrin beta-1 (ITB1) and the receptor of activated protein kinase CComplement activation, lectin pathway, fibrinolysis, and regulation of angiogenesis
CaldesmonActin- and myosin-binding proteinCellular component movement, muscle contraction
ZyxinAdhesion plaque protein. Binds alpha-actinin and the CRP protCell adhesion
DesminClass-III intermediate filaments found in muscle cellsCytoskeleton organization, muscle filament sliding
VimentinVimentins are class-III intermediate filaments found in various nonepithelial cells, especially mesenchymal cIntermediate filament organization
Macrophage-capping proteinCalcium-sensitive protein which reversibly blocks the barbed ends of actin filaments but does not sever preformed actin filaments. May play an important role in macrophage function.Barbed-end actin filament capping, cell projection assembly
F-actin-capping protein subunit alpha-1F-actin-capping proteins bind in a Ca2+-independent manner to the fast growing ends of actin filamentsActin cytoskeleton organization, actin filament capping, cellular component movement

Other proteins
SH3 domain-binding glutamic acid-rich-like proteinSH3/SH2 adaptor activitySH3-binding
Ran-specific GTPase-activating proteinInhibits GTP exchange on RanPositive regulation of GTPase activity
Lymphoid-restricted membrane proteinVesicle fusionVesicle targeting
Chloride intracellular channel protein 1Can be inserted into membranes and form chloride ion channels.Positive regulation of osteoblast differentiation
Enoyl-CoA hydrataseStraight-chain enoyl-CoA thioesters from C4 up to at least C16Fatty acid metabolism
Alpha-internexinClass-IV neuronal intermediate filamentDifferentiation, 
neurogenesis
Fatty acid-binding proteinHigh specificity for fatty acids. Highest affinity for C18 chain length. Transport