Disease relevance of Quality Control

• Aberrant folding and defective trafficking of CFTRDeltaF508 is the principal cause of cystic fibrosis, but how the endoplasmic-reticulum quality-control system targets CFTR for degradation remains unknown [1].
• E. coli has a system of protein quality control surveillance mediated by the ssrA-encoded peptide tagging system [2].
• The FtsH protease slr0228 is important for quality control of photosystem II in the thylakoid membrane of Synechocystis sp. PCC 6803 [3].
• Our results suggest that the exclusion of proteins by the ER quality control system, crosstalk between the EGF- and INF-induced signalling pathways and the regulation of INF-inducible genes are all altered in the prostate cancer cells [4].
• When performing susceptibility testing with H. influenzae with the beta-lactam-beta-lactamase inhibitors, in addition to quality control testing with H. influenzae ATCC 49247, testing of E. coli ATCC 35218 on Haemophilus test medium is an effective way to monitor the beta-lactamase inhibitors in some antimicrobial agent-methodology combinations [5].

Psychiatry related information on Quality Control

• In simple medical classification tasks this dynamic self-learning system can be used to create a DSS that can assist in the quality control of clinical decision making [6].
• A workshop, held in May, 1978, at the National Institute of Child Health and Human Development, considered the quality control of reagents and assays for measuring alpha fetoprotein (AFP) in maternal serum and amniotic fluid for the antenatal screening and diagnosis of open neural tube defects [7].

High impact information on Quality Control

• It has become evident that the modifications that take place in the ER reflect a spectrum of functions related to glycoprotein folding, quality control, sorting, degradation, and secretion [8].
• Loss of SAN1 results in a chronic stress response, underscoring its role of protein quality control in the cell [9].
• Folding and quality control of the VHL tumor suppressor proceed through distinct chaperone pathways [10].
• The Ro 60 kDa autoantigen binds misfolded RNAs and likely functions in small RNA quality control [11].
• AAA proteases comprise a conserved family of membrane bound ATP-dependent proteases that ensures the quality control of mitochondrial inner-membrane proteins [12].

Chemical compound and disease context of Quality Control

• By a checkerboard assay, the combined activities of metronidazole and the hydroxy metabolite were examined against 4 quality control strains of Bacteroides species [13].
• The proposed MIC quality-control range of tigemonam for E. coli ATCC 25922 is 0.13 to 0.5 micrograms/ml [14].
• In 1976, the Center for Disease Control initiated an external quality control program for the isolation and identification of Neisseria gonorrhoeae [15].
• For quality control of ciprofloxacin agar dilution tests on supplemented GC agar, MICs for Staphylococcus aureus ATCC 29213 ranged from 0.12 to 0.5 microgram/ml [16].
• Inconsistent quality control results in disk diffusion testing of cefaclor, cefamandole, cefonicid, and cefuroxime with Haemophilus influenzae ATCC 49247 and Haemophilus test medium (HTM) prompted a search for an alternative control strain that would provide more reliable results [17].

Biological context of Quality Control

• The Structure of calnexin, an ER chaperone involved in quality control of protein folding [18].
• ClpXP is a protease involved in DNA damage repair, stationary-phase gene expression, and ssrA-mediated protein quality control [19].
• Because the Ro protein also binds misfolded 5S rRNA precursors, it is proposed to function in a quality-control pathway for ribosome biogenesis [20].
• Taken together, our results show that several classes of defective RNPs are subject to a quality control step that impedes release from transcription site foci and suggest that suboptimal messenger ribonucleoprotein assembly leads to RNA degradation by Rrp6p [21].
• Ca(2+)-dependent nucleoside diphosphatase may support glycosylation reactions related to quality control in the endoplasmic reticulum [22].

Anatomical context of Quality Control

• The constitutively active endoplasmic reticulum (ER) quality control apparatus is employed to bring about regulated destruction of HMGR [23].
• We suggest that Tul1 provides quality control, identifying misfolded membrane proteins and marking them for transport to endosomes and degradation in the vacuole [24].
• Misfolding diverts CFTR from recycling to degradation: quality control at early endosomes [25].
• Luminal oligosaccharides are transported into the cytosol to ensure that they do not interfere with proper functioning of the glycan-dependent quality control machinery in the lumen of the ER for newly synthesized glycoproteins [26].
• The SsrA or tmRNA quality control system intervenes when ribosomes stall on mRNAs and directs the addition of a C-terminal peptide tag that targets the modified polypeptide for degradation [27].

Associations of Quality Control with chemical compounds

• Consideration of separate lines of work on this versatile pathway now indicate that despite its central role as an avenue of cellular quality control, ERAD is also harnessed for feedback regulation of sterol synthesis, and most likely numerous other cellular processes [28].
• Cytosolic accumulation of prion protein seems to be neurotoxic and might occur when proteasome function is compromised and quality control is overwhelmed [29].
• We report that a key pathway of ER quality control consists of a two-lectin receptor system consisting of Yos9p and Htm1/Mnl1p that recognizes N-linked glycan signals embedded in substrates [30].
• One quality control factor is HtrA, one of a new class of oligomeric serine proteases [31].
• Two central issues in polyglutamine-induced neurodegeneration are the influence of the normal function of the disease protein and modulation by protein quality control pathways [32].

Gene context of Quality Control

• We propose that at this confined site the perinuclear Mlp1 implements a quality control step prior to export, physically retaining faulty pre-mRNAs [33].
• Calnexin is a ubiquitous ER chaperone that plays a major role in quality control by retaining incompletely folded or misfolded proteins [34].
• The truncated cytoplasmic tail of HLA-G serves a quality-control function in post-ER compartments [35].
• Contrasting functions of calreticulin and calnexin in glycoprotein folding and ER quality control [36].
• We conclude that the chaperone PDI is part of the quality control machinery in the ER that recognizes terminally misfolded secretory proteins and targets them to the export channel in the ER membrane [37].

Analytical, diagnostic and therapeutic context of Quality Control

• Method comparison studies showed that the bias and proportional error between the Pierce affinity minicolumn procedure (standardized with respect to an external quality control program) and the Primus HPLC (Y) was -0.4 and 1.2% respectively (n = 32) [38].
• CONCLUSIONS: Equivalent diagnostic sensitivity and specificity were observed with the nonammoniated latex, ammoniated latex, and rubber glove extract skin test reagents after normalization for total protein; nonammoniated latex may be considered the reagent of choice on the basis of practical quality control and reproducibility considerations [39].
• Therefore, screening by immunohistochemistry (IHC) for HER-2 protein, backed by rigorous quality controls and FISH testing of equivocal cases with intermediate staining intensity, remains the current practice [40].
• The apolipoprotein A-I (apo A-I) radioimmunoassay established in our laboratory involves use of purified apo A-I as the primary standard for quantifying apo A-I in plasma and a pooled plasma (quality-control sample) as a secondary standard to decrease interassay variation [41].
• Preliminary experience in external quality control of RT-PCR PML-RAR alpha detection in promyelocytic leukemia [42].

References