RAW 264.7 cells are a macrophage-like, Abelson leukemia virus
transformed cell line derived from BALB/c mice. For routine maintenance in culture (passage), cells are seeded at a confluence of approximately 10% (1 x 106 and 3 x 106 cells in 100-mm and 150-mm plates, respectively) and grown to a confluence of approximately 80%. This procedure requires the cells to be split every two days. - [Read Passage Procedure for RAW 264.7 Cells]
In the routine method described in this protocol, chylomicron-free plasma is adjusted to 12% (w/v) iodixanol and the sample, essentially fills an approx 3 ml tube for a near-vertical rotor. During the centrifugation VLDL, LDL and HDL particles and also plasma proteins migrate from all parts of the sample to their final buoyant density banding position in the self-forming density gradient. - [Read Subfractionation of Low-Density Lipoprotein (LDL)]
DNA microarrays are an ordered arrangement of DNA molecules complementary to genes of interest that are "spotted" by robotic equipment onto a glass slide substrate. The expression of genes in cells can be monitored with microarrays by preparing cDNA from the mRNA of cells of interest and measuring the hybridization to the microarray. This protocol describes the labeling of genomic DNA for use as a probe for hybridization to the cDNA spotted on the array.
The protocol gives general considerations for the design of targeting vectors for transgenic mice. The protocol shares tips in the design of knock-out and knock-in vectors and some of their strategies for producing homologously recombined embryonic stem cells.