ID:PSA_HUMAN DESCRIPTION: RecName: Full=Puromycin-sensitive aminopeptidase; Short=PSA; EC=3.4.11.14; AltName: Full=Cytosol alanyl aminopeptidase; Short=AAP-S; FUNCTION: Aminopeptidase with broad substrate specificity for several peptides. Involved in proteolytic events essential for cell growth and viability. May act as regulator of neuropeptide activity. Plays a role in the antigen-processing pathway for MHC class I molecules. Involved in the N-terminal trimming of cytotoxic T-cell epitope precursors. Digests the poly-Q peptides found in many cellular proteins. Digests tau from normal brain more efficiently than tau from Alzheimer disease brain. CATALYTIC ACTIVITY: Release of an N-terminal amino acid, preferentially alanine, from a wide range of peptides, amides and arylamides. COFACTOR: Binds 1 zinc ion per subunit (By similarity). ENZYME REGULATION: Strongly inhibited by bestatin, leuhistin, actinonin, amastatin, 1,10-phenanthroline, DFP, PCMBS, Zn(2+), Cd(2+), Co(2+), Cu(2+), Hg(2+), EDTA and puromycin. Not inhibited by PMSF, and only slightly inhibited by leupeptin and aprotinin. Activity is increased by Mg(2+) and Ca(2+). BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=2.20 mM for Lys-p-NA; KM=0.25 mM for Leu-p-NA; KM=0.27 mM for Ala-p-NA; KM=0.80 mM for Met-p-NA; KM=0.47 mM for Pro-p-NA; KM=0.21 mM for Val-p-NA; KM=182 uM for Ala-MCA; KM=189 uM for Met-MCA; KM=220 uM for Lys-MCA; KM=91 uM for Leu-MCA; KM=167 uM for Phe-MCA; pH dependence: Optimum pH is 7.5. Stable from pH 5.0 to 8.0; Temperature dependence: Stable up to 40 degrees Celsius; SUBUNIT: Monomer. INTERACTION: P56537:EIF6; NbExp=1; IntAct=EBI-1046129, EBI-372243; SUBCELLULAR LOCATION: Cytoplasm, cytosol. Nucleus (Potential). TISSUE SPECIFICITY: Detected in liver, epithelium of renal tubules, epithelium of small and large intestine, gastric epithelial cells, and alveoli of the lung (at protein level). SIMILARITY: Belongs to the peptidase M1 family. CAUTION: It is uncertain whether Met-1 or Met-45 is the initiator. N-terminal sequencing in PubMed:10978616 suggests that Met-45 is used, followed by methionine initiator removal. SEQUENCE CAUTION: Sequence=AAH65294.2; Type=Erroneous initiation; Note=Translation N-terminally extended; Sequence=CAA68964.1; Type=Erroneous initiation; Note=Translation N-terminally extended;
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on P55786
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Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
Biological Process: GO:0000209 protein polyubiquitination GO:0006508 proteolysis GO:0043171 peptide catabolic process GO:0071456 cellular response to hypoxia GO:1903955 positive regulation of protein targeting to mitochondrion