Protocol describes the transfer of RNA from agarose gels to neutral or positively charged nylon membranes, using upward capillary flow of neutral or alkaline buffers. RNA becomes covalently fixed to positively charged nylon membranes during transfer in alkaline buffers. However, treatment by UV irradiation or heating is required to fix RNA to neutral membranes. - [Read Transfer and Fixation of Denatured RNA to Membranes Protocol]
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.