Pulse and chase experiments

BrdU negative cells during pulse-and-chase experiment (G1 and G2/M)... 

Figure 8. Cell cycle profiles of BrdU negative cells in pulse and chase experiment gated based on BrdU/DNA content dot plot. Cells in the S phase were labelled with BrdU and left in a drug-free medium. Data analysis of BrdU negative cells normalized by cell counting of pulse-labelling experiment was displayed and grey and white area indicated treated or untreated groups by different time point.

Does the nuclear membrane regulate the time of initiation The role of the nuclear membrane in the initiation of DNA synthesis in eukaryote cells is at this time vague. Comings and Kakefuda (1968) demonstrated that the initiation of DNA synthesis takes place at membrane sites at the start of S phase. This association is apparently transient in nature since pulse and chase experiments showed that the radioactivity close to the initiation site moved from the nuclear membrane to the center of the nucleus and the possible importance of this transient association in the development of two growing points has already been stressed. 

Thiolactomycin (TLM) selectively Inhibits type 11 fatty acid synthases from E. coli and higher plants, but does not type 1 fatty acid synthases from Tungi and nKunmals. In this paper, the effect of TLM on fatty acid synthesis is confirmed in enzyme and cell levels. Pulse- and chase-experiments with plant tissues in the presence of TLM accounts for the controlled synthesis of lipids in higher plants. Finally the modulated lipid composition of plant tissues by continuous administration of TLM is examined in relation to the chloroplast structure and the photosynthetic activity of the tissues. 

Data analysis for pulse-labelling and-chase experiment of BrdU labelled and unlabelled fractions normalized for cell count permit to analyze cytostatic and cytotoxic effects during recovery time after lh- treatment. In different cell cycle phases in white area we have shown drug effects for both fractions, while in grey what was expected for untreated samples. 

After approximately 90 min of anoxia, the induced synthesis of an additional group of c. 20 polypeptides is first detected. This group of 20 anaerobic polypeptides (ANPs) represents more than 70% of the total labelled amino acid incorporation after five hours of anaerobiosis (Fig. 3). By this time the synthesis of the TPs is at a minimal level however, these polypeptides accumulate to a high level during early anaerobiosis and have been shown by pulse-chase experiments to be very stable. The synthesis of... 

Metabolic control analysis (MCA) assigns a flux control coefficient (FCC) to each step in the pathway and considers the sum of the coefficients. Competing pathway components may have negative FCCs. To measure FCCs, a variety of experimental techniques including radio isotopomers and pulse chase experiments are necessary in a tissue culture system. Perturbation of the system, for example, with over-expression of various genes can be applied iteratively to understand and optimize product accumulation. 

In the case of trace metals, adsorption is typically much faster than the time intervals for which it is practically possible to separate the cells. Therefore, in practice, values of kf and kr are most often estimated by assuming that water loss from the hydrated cation is rate-limiting (Eigen-Wilkins mechanism, see Section 4.3.1 above). In some cases, uptake transients can be observed at the start of a short-term uptake experiment or by using pulse-chase experiments for which a metal solution containing a radioactive tracer is replaced by a solution... 

Pleurochrysis carterae Fe 7 x 10-4 3 - 9 x 10-4 Pulse-chase experiment and calculation based upon ka [192]... 

H]-ethanolamine into PE was inhibited by C6-ceramide in a dose and time-dependent manner (b) delayed disappearance of label from CDP-choline and CDP-ethanolamine in pulse-chase experiments indicated impaired conversion of these CDP-metaboUtes to PC and PE by CPT and EPT, respectively (c) the activities of CPT and EPT are decreased upon C6-ceramide treatment (see Eigure 2 adapted from Bladergroen et al. 1999b). In contrast to BHK cells the activity of CT was not affected significantly in rat-2 fibroblasts by short-chain ceramides. 

A metabolite, molecular entity, or some other event/ process that precedes another component in a longer sequence of events or conversions. For example, the isoprenoid metabolite squalene is a precursor of cholesterol and glucose 6-phosphate is a precursor of glycogen, ribose, and pyruvate. See Series First Order Reaction Pulse-Chase Experiments... 

The amount of material (e.g., macromolecule or metabolite) metabolized or processed per unit time. 2. The balance between synthesis and degradation of a biomolecule. 3. One complete turn of a reaction cycle. See Turnover Number Protein Turnover Pulse-Chase Experiments Exponential Decay... 

The biological function of this dolichol-linked oligosaccharide was revealed in pulse-chase experiments which showed that the intact oligosaccharide was transferred, as such, to protein. Subsequent studies, to be discussed, confirmed that the formation of the oligosaccharide linked to the Asn residues of glycoproteins is probably initiated by transfer of the oligosaccharide from the dolichol diphosphate intermediate to the asparagine residue of a nascent polypeptide (see Refs. 35, 49, 50, and 67 for reviews). 

Direct observation of the E p/t dNTP complex was obtained using pulse-chase experiments. In such experiments, incorporation of labeled nucleotide to an E p/t complex is either quenched by the addition of HC1 or allowed to proceed after the addition of a large excess of cold unlabeled dNTP (the chase step) followed by acid quench. In the HC1 quench experiments, the acid quenches all the enzyme-bound species. On the other hand, when the reaction is chased with cold dNTP, each of the enzyme-bound species is allowed to partition both in the forward and reverse directions. The amount of partitioning in the forward direction is observed as an excess of labeled product, compared with the acid quench experiment, while the dNTP that partitions in the reverse direction is diluted and remains unobservable. As an excess was observed and because the binding of dNTP to the E p/t complex is rapid, the observed flux or excess is mainly due to the E p/t dNTP complex. 

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