Heavy chains formation

Myosin-II phosphorylation is also an important mechanism for regulating myosin assembly in nonmuscle and smooth muscle cells (Kom and Hammer, 1988). For example, myosin-II ixomAcanthamoeba is more soluble when the heavy chain is phosphorylated compared to the unphosphorylated species. Similarly, phosphorylation of the light chains of vertebrate smooth muscle and nonmuscle myosin-II affects filament formation by these myosins. These myosins undergo a... 

Figure 7.4 Basic structure of an IgG molecule. Two heavy chains (440 residues) and two light chains (214 residues) are joined by disulphide bonds and each shows a relatively constant amino acid sequence in one section (C-terminal end) and a variable sequence section (N-terminal end). The variable regions of both heavy and light chains are involved in the formation of the antigen-binding site.

Somatic hypermutation Mutations occurring in the variable region genes of the light and heavy chains during the formation of memory B cells. Those B cells whose affinity is increased by such mutations are positively selected by interaction with antigen, and this leads to an increase in the average affinity of the antibodies produced. 

Figure 11.6. Schematic diagram showing the assembly of IL-12 protein for antibody-based drug delivery, (a) The mature sequences of the p35 subunit of IL-12 are fused to the C-terminus of the heavy chain of a tumour-specific antibody and co-expressed with the antibody light chain and the p40 subunit of IL-12. Formation of the final immunocytokine requires the creation of disulfide bridges between the antibody chains and interactions of p35 and p40 subunits of IL-12 [119]. (b) Alternatively the IgG heavy chain and both subunits of IL-12 can be linked via flexible linkers allowing for equimolar assembly of IL-12 [120].

Maeda, T., Sugiyama, H., Tani, Y., Miyake, S., Oka, Y., Ogawa, H., Komori, T., Soma, T., Kishimoto, S. (1987). Start of p-chain production by the further two-step rearrangements of immunoglobulin heavy chain genes on one chromosome from a DJH/DJH configuration in an Abelson virus-transformed cell line evidence of secondary DJH complex formation. J. Immunol. 138, 2305-2310. 

Stock, M. F., Guerrero, J., Cobb, B., Eggers, C. T., Huang, T. G., Li, X., and Hackney, D. D. (1999). Formation of the compact conformer of kinesin requires a COOH-terminal heavy chain domain and inhibits microtubule-stimulated ATPase activity. J. Biol. Chem. 274, 14617-14623. 

The second step in the formation of the heavy chain involves transcription of the DNA to form the primary transcript of the RNA of the developing lymphocyte, which includes the new VDJ sequence. This primary transcript (tRNA), however, still includes non-codifying segments (introns). In the third step, these introns are eliminated, and the final RNA includes only the variable N-terminal gene and the genes for all of the constant regions. 

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