CHO Lec3.2.8.1 cells have 4 independent mutations in the N and O glycosylation pathways. When cultured with alpha-glucosidase I inhibitor N-butyl-deoxynojirimycin, glycoproteins produced in CHO Lec3.2.8.1 cells are completely susceptible to Endo H digestion. Endo H cleaves chitobiose, leaving a single N-linked N-acetylglucosamine per site which is ideal for maintenance of protein solubility and special carb-protein interactions, such as between the first N-acetyl glucosamine residue and tryp. - [Read Establishment of Stable Transfectant of CHO Lec Cells Protocol]
Treating cells with paraformaldehyde leads to the establishment of chemical cross-links between free amino groups. When the cross-links join different molecules, a latticework of interactions occurs that holds the overall architecture of the cell together. Commercial formaldehyde solutions are not recommended, because they lack the advantages of using a variable-length polymer, and the cells will simultaneously be fixed with the alcohol (usually methanol). - [Read Fixing Attached Cells in Paraformaldehyde Protocol]
Treating cells with paraformaldehyde leads to the establishment of chemical cross-links between free amino groups. When the cross-links join different molecules, a latticework of interactions occurs that holds the overall architecture of the cell together. - [Read Fixing Suspension Cells with Paraformaldehyde Protocol]
Procedure details the establishment of an amplification procedure for GC-rich sequences. The DNA fragments of interest are amplified in the presence of either 5% DMSO, 1 M betaine, 2 M betaine, 1 M betaine, and 5% DMSO; 2 M betaine and 5% DMSO; 0.4 M tetramethylene sulfone; or without any of the enhancers. - [Read PCR Amplification of Highly GC-Rich Regions Protocol]