X chains

This treatment, resting essentially on the assumed approximate interchangeability of molecules of solvent and solute in the solution, cannot possibly hold for polymer solutions in which the solute molecule may be a thousand or more times the size of the solvent. The long chain polymer may be considered to consist of x chain segTneTits each of which is equal in size to a solvent molecule x is, of course, the ratio of the molar volumes of the solute and solvent. A segment and a solvent molecule may replace one another in the liquid lattice. In other respects the assumptions required are equivalent to those used above. The polymer solution differs from that containing an equal proportion of monomeric solute in the one important respect that sets of x contiguous cells in the lattice are required for accommodation of polymer molecules, whereas no such restriction applies to the solution of the monomeric solute. The situation is illustrated in Fig. 110. 

The transcription activator NF B regulates a variety of genes involved in the immune response and the inflamatory process. NF B is required for the expression of genes for the light x-chain of immimoglobulins, interleukin 2 and 6, as well as for interferon b (see chapter 11). 

The probability that one surrounding chain enters the critical hole is given by V. /V where V is the volume of the solution. The probability w (x) of finding x chains from the total n chains that enter the critical hole is expected to follow the Poisson distribution ... 

Once transfectomas have been generated, they must be screened for the production of the desired fusion. The binding site provided by the expression of the VNP heavy chain in J558L cells and association of the heavy chain with the resident light chain means that the protein fusion can be captured on a solid phase by NP or NIP, and detected using commercially available antibody to mouse X chain and an appropriate enzyme conjugate, in a simple ELISA screening procedure. Similarly, purification can be achieved by affinity adsorption of the fusion onto an NP matrix. An immunoblot method is described here for characterization of selected transfectomas, which allows the mol-wt of the fusion product to be estimated. 

If antiserum to the foreign gene product is available, this can be used in the ELISA with an appropriate conjugate as the revealing reagent instead of antimouse X chain antibody as described below. 

Dilute goat antimouse X chain antibody 1 1000 in PBST and dispense 200 pL/well. Incubate at 37°C for 1 h... 

About 40% of human immunoglobulin light chains are X (Hood et al., 1967). Early studies of X chains produced by patients with multiple myeloma identified four types of C regions that were distinguished serologically and/or by amino acid sequence analysis they appeared not to be allelic and were presumed to be the products of distinct C genes (Appella and Ein, 1967 Ein and Fahey, 1967 Ein, 1968 Hess et al., 1971 Gibson et al., 1971 Fett and Deutsch, 1975). 

The 7 and C gene segments encoding the BALB/c X chains are arranged in two clusters, each 5 kb J jCX2-JXaCxa and CXi (Blomberg et al., 1981 Miller... 

In both the heavy chain and X chain loci of mice and humans, there are a number of C as well as J gene segments. However, in the heavy chain loci, all the J s are clustered separate from the C s whereas in the X loci, each C segment is preceded by a J segment. In the case of heavy chains, any of the 7H can, at least in principle, be expressed in association with any of the CH, whereas in X chains, J -C pairing is fixed. 

The first persuasive, albeit indirect, evidence that antibodies are diversified by somatic mutation came from the analysis of mouse X light chains by Weigert et al. (1970). In the initial experiments, V regions of ten X chains, obtained from mouse plasmacytomas, were examined by peptide mapping and partial sequence analysis. 

Gibson, D., Levanon, M., Smithies, O. (1971). Heterogeneity of normal human immunoglobulin light chains. Nonallelic variation in the constant region of X chains. Biochemistry 10, 3114-3122. 

Honjo, T., Packman, S., Swan, D., Leder, P. (1976). Quantitation of constant and variable region genes for mouse immunoglobulin X chains. Biochemistry 15, 2780-2785. 

Takeda, S., Zou, Y.-R., Bluethmann, H., Kitamura, D Muller, U., Rajewsky, K. (1993). Deletion of the immunoglobulin K chain intron enhancer abolishes K chain gene rearrangement in cis but not X chain gene rearrangement in trans. EMBO J. 12,2329-2336. 

Figures 35 and 36 reveal that for each copolymer studied, the average aggregation number (ATagg) and average hydrodynamic radius ((%)) of polymer clusters made of collapsed and associated P(DEA-co-DMA/x) chains increase and approach corresponding constants after a certain time, indicating the for-...

ATP synthesis protein 8 HMG CoA-reductase Cholesterol 7a-hydroxylase ATP synthesis X chain... 

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