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PubMed1984

Temperature-dependent dissociation of Lucké renal adenocarcinoma cells.

Fragments of Lucké renal adenocarcinoma were subjected to dissociation by rapid shaking after exposure to a divalent cation-free electrolyte solution, with or without 5 X 10(-4) M ethylenediaminetetraacetate (EDTA), at 7 degrees C and 28 degrees C. More cells detached at 28 degrees C than at 7 degrees C. Dissociation of cells from normal mesonephros fragments was minimal at both temperatures. It has been shown else-where that this frog tumor elaborates collagenase in a temperature-dependent manner. More collagenase is detected at 30 degrees C than at 7 degrees C. Normal kidney elaborates low levels of collagenase at both temperatures. Because our results suggested the possibility that some dissociation of the tumor cells may have been attributable to tumor-elaborated collagenase, we studied the effect of two collagenase inhibitors on dissociation. Both EDTA at high concentration and cysteine inhibit collagenase and both diminished tumor-cell dissociation.

Adenocarcinoma↗
PubMed1976

Yeast hexokinase: substrate-induced association--dissociation reactions in the binding of glucose to hexokinase P-II.

A method is described for the purification of native hexokinases P-I and P-II from yeast using preparative isoelectric focussing to separate the isozymes. The binding of glucose to hexokinase P-II, and the effect of this on the monomer--dimer association--dissociation reaction have been investigated quantitatively by a combination of titrations of intrinsic protein fluorescence and equilibrium ultracentrifugation. Association constants for the monomer-dimer reaction decreased with increasing pH, ionic strength and concentration of glucose. Saturating concentrations of glucose did not bring about complete dissociation of the enzyme showing that both sites were occupired in the dimer. At pH 8.0 and high ionic strength, where the enzyme existed as monomer, the dissociation constant of the enzyme-glucose complex was 3 X 10(-4) mol 1(-1) and was independent of the concentration of enzyme. Binding to the dimeric form at low pH and ionic strength (I=0.02 mol 1(-1), pH less than 7.5) was also independent of enzyme concentration (in the range 10-1000 mug ml-1) but was much weaker. The process could be described by a single dissociation constant, showing that the two available sites on the dimer were equivalent and non-cooperative; values of the intrinsic dissociation constant varied from 2.5 X 10(-3) mol 1(-1) at pH 7.0 to 6 X 10(-3) at pH 6.5. Under intermediate conditions (pH 7.0, ionic strength=0.15 mol 1(-1)), where monomer and dimer coexisted, the binding of glucose showed weak positive cooperatively (Hill coefficient 1.2); in addition, the binding was dependent upon the concentration of enzyme in the direction of stronger binding at lower concentrations. The results show that the phenomenon of half-sites reactivity observed in the binding of glucose to crystalline hexokinase P-II does not occur in solution; the simplest explanation of our finding the two sites to be equivalent is that the dimer results from the homologous association of two identical subunits.

Binding Sites↗
PubMed1977

Studies by small-angle x-ray scattering of the quaternary structure of dissociation products of the beta-haemocyanin of Helix pomatia.

Helix pomatia beta-haemocyanin was split into dissociation products by varying the pH and the ionic strength. The purity of the solution was checked in an ultracentrifuge. Two defined dissociation products were studied in solution by small-angle X-ray scattering. In Tris-HC1 buffer, pH 8.0 and ionic strength 1 M, the following parameters of the dissociation product (tenths) could be determined: molecular weight = 7 x 10(5), volume = 1350 nm3, radius of gyration = 9.0 nm, maximal distance = 28.3 nm, radius of the spherical subunits about 2.6 nm, number of the subunits approximately 19. Tris-HC1 buffer, pH 8.7 and ionic strength 0.01 M, yielded dissociation products (twentieths) with the following parameters: molecular weight = 3.5 x 10(5), volume = 635 nm3, radius of gyration = 7.5 nm, maximal distance = 21.9 nm, radius of the spherical subunits about 2.5 nm. With this information, the assumption that the larger fragment was double the smaller one and the latest biochemical and morphological results, theoretical scattering curves of models were calculated and compared with the experimental curves. Two models are suggested which argee well with the dissociation products in radius of gyration and scattering.

Animals↗
PubMed1977

[Methionyl-tRNA synthetase from wheat embryo: dissociation into subunits (author's transl)].

Wheat -embryo methionyl-tRNA synthetase is a dimeric protein of beta2 structure. When highly diluted, it loses the capacity to catalyze ATP-[32P]PPi exchange and to aminoacylate tRNAMet: at low enzymatic concentrations the rates of formation of[32P]ATP and [14C]methionyl-tRNAMet are lower than those predicatedby extrapolating the rates determined at higher enzyme concentrations. The difference between observed and expected rates becomes greater with decreasing enzyme concentration. Filtration of purified, dilute enzyme preparations on Sephadex G-200 results in the separation of dimer and monomer fractions. The proportion of monomer present increases with increasing pre-incubation times before the assay and demonstrates an equilibrium between active dimers and being shifted towards the production of monomers. Datapreviously gathered for Escherichia coli prolyl-tRNA synthetase and for bovine-pancreatic tryptophanyl-tRNA synthetase, coupled with the present results, suggests that the dissociation of dimeric synthetases may be a general phenomenon in eukaryotes as well as in prokaryotes. The number of sub-units and the dissociation constant were obtained at equilibrium, according to relations adapted to the case of oligomeric enzymes (KD congruent to 13 nM at 25 degrees C and pH 7.5). Rate constants were determined by kinetic studies of the attainment of equilibrium. The rate constant k1 for monomolecular dissociation was determined to be 1.85- 10-3 s-1 and k2 for the bimolecular association to be 0.145 - 106 M-1 s-1. The KD calculated from k1 and k2 was coherent with the experimentally determined value, at equilibrium. The sub-unit interactions, which involve only a small quantity of energy (delta G degree congruent to + 11 kcal mol-1; +45 kJ mol-1) at 25 degrees C, depend on the ionic environment of the medium and the presence of substrates. Alkaline pH favors monomer production, while the presence of methionine, (Mg-ATP)2- and tRNAMet protect the synthetase from dissociation. 2-mercaptoethanol and dithioerythritol prevent only slightly the loss of activity. Bovine serum albumin, however, protects the enzyme from dissociation under dilute conditions.

Amino Acyl-tRNA Synthetases↗
PubMed1984

Diamine-induced dissociation of the first component of human complement, C1.

Lysine has been shown to inhibit spontaneous and antibody-dependent C1 activation. This paper demonstrates that lysine does not prevent autoactivation of purified C1r. 20 mM lysine, 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane or 1,5-diaminopentane are able to dissociate C1 into its two entities, C1q and the calcium-dependent C1r2-C1s2 complex. Ig-ovalbumin insoluble complexes bearing C1 are also dissociated by lysine and the above-mentioned diamines used at the same concentration: C1q remains bound to the complexes whereas the C1r2-C1s2 complex is partially solubilized. The effect of lysine or diamines is not due to a competition with calcium for calcium-binding sites, as increasing concentrations of calcium even slightly increase the dissociation due to the amines. The dissociative effect is dependent on the carbon chain length of the diamines, with an optimum for 1,3-diaminopropane. It is also dependent on the relative 'cis-position' of the amino groups in the diamines. Polyamines such as spermine and spermidine are also able to dissociate C1 with even a higher efficiency than lysine and putrescine. Thus, a diamine-induced 'structural inhibition' of C1 is demonstrated, of potential interest for a pharmacological control of complement activation.

Calcium↗
PubMed1985

Kinetics of calcium dissociation from calmodulin and its tryptic fragments. A stopped-flow fluorescence study using Quin 2 reveals a two-domain structure.

The kinetics of calcium dissociation from bovine testis calmodulin and its tryptic fragments have been studied by fluorescence stopped-flow methods, using the calcium indicator Quin 2. Two distinct rate processes, each corresponding to the release of two calcium ions are resolved for calmodulin at both low and high ionic strength. The effect of 0.1 M KCl is to accelerate the slow process from 9.1 +/- 1.5 s-1 to 24 +/- 6.0 s-1 and to reduce the rate of the fast process from 650 s-1 to 240 +/- 50 s-1 at 25 degrees C. In the presence of 0.1 M KCl it was possible to determine activation parameters for the fast process: delta H# = 41 +/- 5 kJ mol-1 and delta S# = -63 +/- 17 J K-1 mol-1. These values are in good agreement with those obtained by 43Ca NMR. Studies of the tryptic fragments TR1C and TR2C, comprising the N-terminal or C-terminal half of calmodulin, clearly identified Ca2+-binding sites I and II as the low-affinity (rapidly dissociating) sites and sites III and IV as the high-affinity (slowly dissociating) sites. The kinetic properties of the two proteolytic fragments are closely similar to the fast and slowly dissociating sites of native calmodulin, supporting the idea that calmodulin is constructed from two largely independent domains. The presence of the calmodulin antagonist trifluoperazine markedly decreased the Ca2+ dissociation rates from calmodulin. One of the two high-affinity trifluoperazine-binding sites was found to be located on the N-terminal half and the other on the C-terminal half of calmodulin. The affinity of the C-terminal site is at least one order of magnitude greater.

Aminoquinolines↗
PubMedDate not supplied

Dissociations, developmental psychology, and pedagogical design.

Although dissociations in children's responses are sometimes about "getting it right" for an experimenter, they might also often reflect differences between conscious and subconscious processing that are not geared to correct performance. Research with adults also reveals many cases of dissociation, and adults can more easily be subjected to neuroimaging methods that might help shed light on dissociation. Finally, much of the research on dissociations shows that human cognition is optimized in some contexts over others. School environments often correspond to less optimizing contexts. Research on dissociation could be used to inform pedagogical design.

Awareness↗
PubMed1984

Glutamine oxidation by dissociated cells and homogenates of rat brain: kinetics and inhibitor studies.

The rates of [U-14C]glutamine oxidation to 14CO2 were determined under a variety of experimental conditions using whole homogenates and dissociated cells from rat brain. The pattern of glutamine oxidation by homogenates differed from that by dissociated brain cells in several respects. The rates of glutamine oxidation by dissociated brain cells showed saturation kinetics with an apparent Km of 0.30 mM. Lineweaver-Burk plots of glutamine oxidation by homogenates revealed two linear segments with two apparent Km values (0.58 mM and 3.0 mM). In the presence of aminooxyacetate, however, the Lineweaver-Burk plots for homogenates were linear with a single Km of 0.47 mM. The oxidation of glutamine by homogenates was inhibited by both rotenone and antimycin A (80-85%), as were glutamate and glucose oxidation, suggesting that a significant amount of glutamine is oxidized via the tricarboxylic acid cycle. In the presence of aminooxyacetate, glutamine oxidation was inhibited less than 40%, whereas the oxidation of glutamate was inhibited 75%; in contrast, glucose oxidation was enhanced 50%. The rates of glutamine oxidation by homogenates were highest in the presence of high levels of potassium (50 mM) and low levels of sodium (2.5 mM). Varying ionic composition, however, had little or no effect on the rates of glutamine oxidation by dissociated brain cells. Measurements of glutamine oxidation by homogenates prepared from 2-, 10-, 15-, 25-, and 90-day-old rats revealed little or no age-dependent difference. In contrast, the oxidation by dissociated brain cells from 2-day-old animals was significantly less than that obtained for animals 10 days or older (7.76 vs. 15.6 nmol/h/mg).(ABSTRACT TRUNCATED AT 250 WORDS)

Aminooxyacetic Acid↗
PubMed1985

Effects of guanyl nucleotides on [3H]flunitrazepam binding to rat hippocampal synaptic membranes: equilibrium binding and dissociation kinetics.

The effects of guanyl nucleotides on the binding of [3H]flunitrazepam to rat hippocampal synaptic membranes were studied. In equilibrium binding studies, gamma-amino-n-butyric acid (GABA) increased and GTP decreased the binding affinity of [3H]flunitrazepam; GTP also caused a decrease in binding capacity. The effect, however, is variable. In studies of the dissociation kinetics of [3H]flunitrazepam using diazepam and the antagonist Ro 15-1788 as the displacers, there was evidence of two dissociation rate constants. GTP increased both the fast- and slow-dissociation rate constants and increased the ratio of the slow-dissociation binding state. The effect of GTP was mimicked by its nonhydrolyzable analogue 5'-guanylylimidodiphosphate but not by ATP and occurred when diazepam, but not when Ro 15-1788, was used as the displacer. GABA antagonized the effect of GTP on the dissociation of [3H]flunitrazepam. The nature of the benzodiazepine receptor, its actions, and the possible role of cyclic AMP as a second messenger are discussed.

Adenosine Triphosphate↗
PubMed1996

Effects of prenatal ethanol exposure on voltage-dependent calcium entry into neonatal whole brain-dissociated neurons.

The effect of prenatal ethanol exposure on voltage-dependent calcium entry into neonatal-dissociated neurons was studied. Dissociated whole brain cells were isolated from neonates of prenatally ethanol-treated (ET), pair-fed (PF) control, and ad libitum (AL) control groups and loaded with fura-2. Prenatal ethanol exposure resulted in a significant reduction of calcium entry into K(+)-depolarized cells, compared with AL and PF control treatments. Initially, in dissociated cells from AL control animals, it was found that nifedipine (1 microM), omega-agatoxin (100 nM), and omega-conotoxin (500 nM), to a much lesser extent, significantly inhibited the 45 mM KCl-stimulated calcium entry. To determine the inhibitory action of prenatal ethanol exposure on N-, P-, and L-type voltage-dependent calcium channels, treatment of neonatal-dissociated neurons with different combinations of omega-conotoxin, omega-agatoxin, and nifedipine, respectively, was compared in the prenatal ethanol and control treatment groups. The inhibition of K(+)-stimulated increase in calcium entry by prenatal ethanol exposure was significantly less in the presence or absence of single antagonist conditions (ET < AL and PF). There was no apparent interaction of ethanol exposure and antagonist condition. However, the reduced calcium entry after prenatal ethanol exposure was superseded by the stronger inhibition in dual and triple antagonist conditions. The magnitude of the calcium response inhibition by the antagonist combinations was similar among the ET, PF, and AL groups. Thus, these results suggest that prenatal ethanol exposure decreases voltage-dependent calcium entry into neonatal-dissociated neurons in a manner that does not seem to involve the selective inhibition of any individual N-, P-, or L-type calcium channel.

Animals↗
PubMed2006

Novel dissociation mechanism of a polychaetous annelid extracellular haemoglobin.

The extracellular haemoglobin of the marine polychaete, Arenicola marina, is a hexagonal bilayer haemoglobin of approximately 3600 kDa, formed by the covalent and noncovalent association of many copies of both globin subunits (monomer and trimer) and nonglobin or 'linker' subunits. In order to analyse the interactions between globin and linker subunits, dissociation and reassociation experiments were carried out under whereby Arenicola hexagonal bilayer haemoglobin was exposed to urea and alkaline pH and the effect was followed by gel filtration, SDS/PAGE, UV-visible spectrophotometry, electrospray-ionization MS, multiangle laser light scattering and transmission electron microscopy. The analysis of Arenicola haemoglobin dissociation indicates a novel and complex mechanism of dissociation compared with other annelid extracellular haemoglobins studied to date. Even though the chemically induced dissociation triggers partial degradation of some subunits, spontaneous reassociation was observed, to some extent. Parallel dissociation of Lumbricus haemoglobin under similar conditions shows striking differences that allow us to propose a hypothesis on the nature of the intersubunit contacts that are essential to form and to hold such a complex quaternary structure.

Animals↗
PubMed1971

Human thyroxine-binding globulin and thyroxine-binding pre-albumin: dissociation rates.

1. A simple method is described for estimating the rate of thyroxine dissociation from binding sites in plasma.2. At tracer concentrations in human plasma thyroxine dissociates at two distinct exponential rates. These are due to the two thyroxine-binding proteins present in human plasma.3. The t((1/2)) for thyroxine dissociation from thyroxine-binding globulin is 8.1 +/- 0.7 (S.E.) min at room temperature and 38.6 +/- 2.1 sec at 37 degrees C.4. The t((1/2)) for thyroxine dissociation from thyroxine-binding pre-albumin is 53 +/- 5.0 sec at room temperature and 7.9 +/- 0.3 sec at 37 degrees C.5. Dissociation of thyroxine from both proteins is a single exponential process, suggesting that each protein has only one type of specific binding site.6. These results indicate that the minute pool of free thyroxine in plasma is turning over about 100 times each second, with about two thirds of this flux being due to release and binding of the hormone by pre-albumin.

Binding Sites↗
PubMed2001

Involvement of IQGAP1, an effector of Rac1 and Cdc42 GTPases, in cell-cell dissociation during cell scattering.

We have previously proposed that IQGAP1, an effector of Rac1 and Cdc42, negatively regulates cadherin-mediated cell-cell adhesion by interacting with beta-catenin and by causing the dissociation of alpha-catenin from cadherin-beta-catenin-alpha-catenin complexes and that activated Rac1 and Cdc42 positively regulate cadherin-mediated cell-cell adhesion by inhibiting the interaction of IQGAP1 with beta-catenin. However, it remains to be clarified in which physiological processes the Rac1-Cdc42-IQGAP1 system is involved. We here examined whether the Rac1-IQGAP1 system is involved in the cell-cell dissociation of Madin-Darby canine kidney II cells during 12-O-tetradecanoylphorbol-13-acetate (TPA)- or hepatocyte growth factor (HGF)-induced cell scattering. By using enhanced green fluorescent protein (EGFP)-tagged alpha-catenin, we found that EGFP-alpha-catenin decreased prior to cell-cell dissociation during cell scattering. We also found that the Rac1-GTP level decreased after stimulation with TPA and that the Rac1-IQGAP1 complexes decreased, while the IQGAP1-beta-catenin complexes increased during action of TPA. Constitutively active Rac1 and IQGAP1 carboxyl terminus, a putative dominant-negative mutant of IQGAP1, inhibited the disappearance of alpha-catenin from sites of cell-cell contact induced by TPA. Taken together, these results indicate that alpha-catenin is delocalized from cell-cell contact sites prior to cell-cell dissociation induced by TPA or HGF and suggest that the Rac1-IQGAP1 system is involved in cell-cell dissociation through alpha-catenin relocalization.

Animals↗
PubMed1989

Inhibition and dissociation of [3H]-paroxetine binding to human platelets.

Previous data on dissociation studies of [3H]-imipramine and [3H]-paroxetine binding to the human platelet 5-hydroxytryptamine (5-HT, serotonin) transporter have suggested that the binding is heterogeneous in nature and/or is subject to allosteric modifications through a separate low affinity site. The platelet 5-HT transporter is often used as a biological marker in psychiatric conditions. Therefore, it was of interest to further characterize the 5-HT uptake site by using [3H]-paroxetine. The 5-HT uptake inhibitors tested (citalopram, clomipramine, imipramine, norzimeldine and paroxetine) and 5-HT itself produced competitive inhibition patterns in saturation experiments, suggesting that these agents bind to the same site. In dissociation experiments in the presence of the 5-HT uptake inhibitors, the half-time values for dissociation were the same, whereas 5-HT slowed the dissociation. These data suggest that with the concentrations used of the 5-HT uptake inhibitors, they do not modify the 5-HT transporter. However, in the presence of 5-HT, the [3H]-paroxetine dissociation is decreased, suggesting an allosteric modification of the [3H]-paroxetine binding site.

Antidepressive Agents↗
PubMed1982

X-Y chromosome dissociation in wild derived Mus musculus subspecies, laboratory mice, and their F1 hybrids.

The frequencies of X and Y chromosome dissociation in primary spermatocytes of wild-caught specimens of six Mus musculus subspecies, fifteen inbred mouse strains, and their F1 hybrids were examined. Three different types (I, II, and III) of X-Y dissociation were identified. Type I was found in inter-subspecies hybrids (BALB/c X M. m. molossinus, M. m. bactrianus, M. m. castaneus, or M. m. urbanus), in which the X-Y dissociation was less than 20% in each subspecies but 60-80% in the f1 hybrids. Type II was seen in the DBA/2J and DDK strains, in which the dissociation frequency was about 30% in the homozygous condition and increased up to 50% in inter-strain hybrids (C57BL/6J X DBA/2J or DDK). Type III found in the WB/Re strain also showed high dissociation frequency (51.1%) in the homozygous condition but the value was remarkably lower (11.3%) in C57BL/6J X WB/Re)F1s. Some asian wild mice seem to have type II or III as well as type I.

Animals↗
PubMed1978

Binding of 14C-ADP to normal human and thrombasthenic platelet membranes. Study of the dissociation of the nucleotide from its receptors.

Normal and thrombasthenic platelet membranes are able to specifically bind 14C-ADP (12). According to the concentration of ADP present in the medium, 'high affinity binding sites' (Ka = 0.5 X 10(6) M-1 and 'low affinity-binding sites' (Ka = 0.05 X 10(6) M-1) can be recognized. In the present study, dissociation of ADP from the 'high affinity binding sites' was measured with six normal and with three thrombasthenic platelet membrane preparations. A 1:100 dilution was used to dissociate the membrane-bound 14C-ADP and the kinetics of the dissociation was determined. The same profile of dissociation (with T 1/2 = 4--10 min at 37 degrees C) was observed using normal or thrombasthenic membranes. With both preparations, the rate of dissociation was increased (up to T 1/2 = 1--3 min) when unlabelled ADP (at concentration higher than 10(-5) M) was added in the diluting medium. The results confirm the presence of normal ADP binding sites on thrombasthenic platelet membrane and possibly suggest the existence of cooperative interactions between the sites on normal as well as on thrombasthenic membranes.

Adenosine Diphosphate↗
PubMed2005

Altered gene expression of angiogenic factors induced by calcium-mediated dissociation of retinal pigment epithelial cells.

PURPOSE: To examine the effect of loss of cell-cell contacts on the gene expression of vascular endothelial growth factor (VEGF) and other factors in primary culture of human retinal pigment epithelial (RPE) cells with real-time reverse transcription-PCR. METHODS: The dissociation of postconfluent RPE cells was induced by calcium chelation, low-calcium medium, anti-E-cadherin, and anti-N-cadherin antibodies. Total RNA was isolated from the cultured RPE cells and reverse transcribed to cDNA. VEGF was quantified by real-time PCR with a fluorescence detector. VEGF isoforms were differentially measured by specific exon-spanning primers. Besides VEGF, the gene expression levels of some other growth factors were also examined in calcium-mediated dissociation. RESULTS: Disruption of cell-cell contacts of RPE cells was induced by calcium chelation and low-calcium medium, but not by anti-E-cadherin and anti-N-cadherin antibodies. Calcium-mediated dissociation of RPE cells significantly increased the gene expression levels of VEGF. The mRNA levels of VEGF increased by 6.3-fold on treatment with EGTA and by 4.7-fold in the low-calcium medium at 6 hours. Splice variants of VEGF showed the differential pattern of gene expression. Whereas the expression of VEGF(121) and VEGF(165) was upregulated on calcium-induced dissociation of RPE cells, that of VEGF(145) and VEGF(189) was unchanged. VEGF(206) was not detected. On calcium-induced dissociation, bFGF, IL-6, matrix metalloproteinase (MMP)-1, and placental growth factor (PlGF) were upregulated, whereas acidic (a)FGF and pigment epithelium-derived factor (PEDF) were both downregulated. CONCLUSIONS: The results show that loss of intercellular contacts promotes increased gene expression of VEGF and other angiogenic factors in human RPE cells.

Actins↗
PubMed1975

Distribution of concanavalin A binding sites on the surface of dissociated rat submandibular gland acinar cells.

The submandibular glands of 4-week-old rats were dissociated by a procedure involving digestions with collagenase and hyaluronidase, chelation of divalent cations and mechanical force. A suspension of single cells was obtained in low yield by centrifugation in a Ficoll-containing medium. Immediately after dissociation and after a culture period of 16-18 hr the dissociated cells were tested for agglutinability by concanavalin A (Con A). Using ferritin (tfer)-conjugated Con A the lectin binding by the isolated acinar cells was also studied. The dissociated cells were agglutinated by low concentrations of Con A and bound Fer-Con A molecules on their entire surface without any indication of polarization of the cell membrane. There was a considerable cell to cell variation in the amount of Fer-Con A binding which was, in general, sparse and patchy. The contact surfaces between agglutinated cells revealed a dense binding of Fer-Con A molecules irrespective of the types of cells participating in the agglutination reaction. Cells cultured for 16-18 hr were no longer agglutinated by Con A. As compared to the freshly dissociated cells the cultured acinar cells revealed a more uniform and denser binding of Fer-Con A molecules. Furthermore, there were more lectin molecules bound to the cell surface corresponding to the basal part of the cell, where the nucleus and most of the rough surface endoplasmic reticulum were located, than to the apical cell surface. It is suggested that the higher density of lectin-binding sites on the cell surface in the vicinity of the cisternae of the rough endoplasmic reticulum indicates insertion sites of newly synthesized membrane glycoproteins.

Agglutination Tests↗