All articles starting with P
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Protein male-specific lethal-1
Protein male-specific lethal-1 (MSL1), Drosophila scaffold of the MSL dosage compensation complex; dimerizes, binds MSL2, MSL3, MOF, targets the male X chromosome; loss causes male-specific lethality.
Protein melted-like
Protein melted-like (InterPro IPR039888, MELT/VEPH family): animal proteins with a C-terminal PH domain, from Drosophila melted (Q9VS24) to vertebrate VEPH1, regulating insulin/TOR and TGF-beta signaling.
Protein metabolism
Protein metabolism covers protein synthesis on ribosomes, protein degradation via the ubiquitin-proteasome and autophagy-lysosome systems, amino acid catabolism, and nitrogen disposal through the hepatic urea cycle, with dietary requirements of roughly 0.75 g/kg/day for adults.
Protein methylation
Protein methylation is a post-translational modification adding methyl groups from SAM to lysine, arginine, and other residues, catalyzed by PKMTs and PRMTs, read by methyllysine-binding domains, and regulating transcription, signaling, DNA repair, and cancer-related pathways.
Protein Metrics
Protein Metrics is an American software company making vendor-neutral mass-spectrometry analysis software for proteomics and biotherapeutic protein characterization, known for the Byonic search engine and 30 patents.
Protein microarray
A protein microarray is a glass slide or chip on which many proteins are immobilized at high density, measuring binding events and interactions in parallel.
Protein misfolding cyclic amplification
Protein misfolding cyclic amplification (PMCA) is a laboratory technique, first described in 2001 by Saborio and colleagues, that exponentially amplifies minute quantities of misfolded prion protein through incubation and sonication cycles.
Protein MutL
MutL/MLH/PMS proteins are the conserved coordinators of DNA mismatch repair, forming homodimers in bacteria and MLH1-centered heterodimers in eukaryotes; loss causes Lynch syndrome and defines immunotherapy-responsive tumors.
Protein myomixer
Protein myomixer (MYMX, also Myomerger or Minion) is an 84-amino-acid muscle-specific membrane micropeptide that partners with Myomaker to drive myoblast fusion, muscle formation, and regeneration in vertebrates.
Protein NPAT
NPAT (nuclear protein, ataxia-telangiectasia locus; coactivator of histone transcription) is a human chromosome 11 protein that, phosphorylated by cyclin E-Cdk2, activates replication-dependent histone genes and scaffolds the histone locus body; Drosophila ortholog is Multi sex combs (Mxc).
Protein O-mannosyltransferase
Protein O-mannosyltransferase (POMT1/POMT2, yeast PMT1-7) is an ER glycosyltransferase complex transferring mannose from dolichol-phosphate-mannose to serine/threonine, initiating O-mannosylation of alpha-dystroglycan; mutations cause Walker-Warburg syndrome and dystroglycanopathies.
Protein OBERON
Protein OBERON (OBE1-OBE4) is a family of four nuclear PHD-finger chromatin proteins in Arabidopsis thaliana that maintain shoot and root meristems, specify vasculature, and drive phloem development with SMXL5.
Protein origami
Protein origami is a design strategy in which polypeptide chains built from modular coiled-coil segments fold into polyhedral nano-cages; the 2017 Ljubljana demonstration produced more than 20 single-chain cages.
Protein P
Protein P is the HBV polymerase, a four-domain multifunctional enzyme (terminal protein, spacer, RT, RNase H) that reverse-transcribes viral pgRNA via protein priming at Y63 and is the target of nucleos(t)ide analog drugs such as entecavir and tenofovir.
Protein Patronus
Protein Patronus (PATRONUS, PANS1/PANS2) is the plant securin family in Arabidopsis thaliana: intrinsically disordered APC/C-regulated inhibitors of separase that protect centromeric cohesion at meiosis, homologous to animal securins.
Protein phosphatase 1
Protein phosphatase 1 (PP1, PP1c), a major eukaryotic serine/threonine phosphatase of the PPP family; an obligatory holoenzyme with over 200 RVxF-motif regulatory subunits regulating glycogen metabolism, muscle contraction, and cell cycle.
Protein phosphatase 2
Protein phosphatase 2 (PP2A) is a heterotrimeric serine/threonine phosphatase (A scaffold, C catalytic, B55/B56/PR72/striatin regulatory subunits; 92 possible holoenzymes) that dephosphorylates over 300 substrates, opposes WNT/mTOR/MAPK kinases, and is linked to cancer and Alzheimer's tau pathology.
Protein phosphatase 2C
Protein phosphatase 2C (PP2C, PPM family): monomeric Mg2+/Mn2+-dependent serine/threonine phosphatases, okadaic acid-resistant, unrelated to PP1/PP2A/PP2B; 16 human genes, regulators of stress signaling, cell cycle, and plant ABA signaling.
Protein phosphorylation
Protein phosphorylation: kinase-catalyzed transfer of ATP phosphate to serine, threonine, or tyrosine residues, the most common post-translational modification; reversed by phosphatases, discovered by Fischer and Krebs (1992 Nobel Prize), and a major drug-target class.
Protein precipitation
Protein precipitation: making dissolved proteins insoluble by salting out (ammonium sulfate), isoelectric precipitation at the pI, or PEG and organic solvents; the oldest protein purification technique, rooted in Hofmeister's 1888 ion series.
Protein PsiB
Protein PsiB (Plasmid SOS Inhibition protein B) is a small plasmid-encoded bacterial protein, about 12 kDa, that suppresses the bacterial SOS response by sequestering free RecA protein.
Protein purification
Protein purification isolates one protein from biological mixtures using chromatography (ion exchange, size exclusion, HIC, affinity), precipitation, and filtration; central to biopharmaceutical manufacture, where downstream processing is about 75% of manufacturing cost.
Protein PUTATIVE RECOMBINATION INITIATION DEFECT 1
PRD1 (AtPRD1, AT4G14180) is a 1,330-aa Arabidopsis protein, homolog of mammalian MEI1, required for meiotic double-strand break formation and chiasma assembly; interacts with SPO11-1, PRD3, DFO, MTOPVIB. Not bacteriophage PRD1.
Protein quaternary structure
Protein quaternary structure: the defined organization of two or more tertiary-structured subunits (protomers) held by hydrogen bonds, van der Waals, and coulombic forces; exemplified by hemoglobin's T/R tetramer, enabling cooperativity and allostery.
Protein Rds1
Protein Rds1: fungal proteins named Rds1, chiefly the 832-aa zinc cluster transcription factor Rds1p of Saccharomyces cerevisiae (cycloheximide resistance) and the adenine-repressible, stress-regulated conserved fungal protein rds1 of Schizosaccharomyces pombe; distinct from retinal retinoschisin RS1.
Protein Red-like
Protein Red-like (InterPro IPR039896) is a eukaryotic protein family named for the RED repeat of arginine, glutamic acid, and aspartic acid. Its human member, protein Red (IK), is a disordered auxiliary spliceosomal factor that with SMU1 activates the spliceosome.
Protein refolding
Protein refolding converts unfolded or aggregated proteins, typically recovered from E. coli inclusion bodies, back into their native three-dimensional structure, a key and costly step in biopharmaceutical manufacturing.
Protein repair
Protein repair (GO:0030091; Reactome R-HSA-5676934) is enzymatic reversal of protein chemical damage, mainly methionine sulfoxide reduction by MSRA/MSRB, isoaspartyl repair by PIMT, and deglycation by fructosamine-3-kinase.
Protein S10
Protein S10 (ribosomal protein S10, uS10, RPS10, P46783; viral Protein S10, P19898 VP10_RBSDV) is a small ribosomal subunit protein in 40S/30S subunits, or an unrelated Rice black-streaked dwarf virus protein of the same name.
Protein secondary structure
Protein secondary structure: regular local backbone conformations, chiefly the alpha helix (3.6 residues/turn, i to i+4 hydrogen bonds) and beta sheet, proposed by Pauling, Corey, and Branson in 1951 and predictable at about 80% Q3 accuracy.