Microarray analysis of gene expression refers to a powerful genomic technology used to simultaneously measure the expression levels of thousands of genes within a biological sample. It involves the use of a microarray, which is a glass slide or a small chip containing microscopic DNA spots that represent specific genes.
The process begins with the isolation and purification of RNA molecules from the sample of interest, which represents the genes that are actively being transcribed. This RNA is then converted into complementary DNA (cDNA) through a process called reverse transcription. The cDNA is fluorescently labeled, with different samples being labeled with different colors. These labeled cDNA samples are then applied to the microarray slide and incubated, allowing the cDNA to hybridize or bind to complementary DNA sequences on the slide.
After washing off any unbound or nonspecifically bound cDNA, the slide is scanned using a specialized instrument that detects and quantifies the intensity of the fluorescent signals emitted by each spot on the microarray. The intensities are directly proportional to the abundance of the corresponding gene's mRNA in the original sample.
The data obtained from the microarray analysis is then analyzed using statistical methods and bioinformatics tools to identify differentially expressed genes, which are genes that show significantly altered expression levels between different samples or conditions. This analysis provides valuable insights into the molecular mechanisms underlying biological processes, such as disease development and progression, cellular responses to stimuli, or drug effects.
In summary, microarray analysis of gene expression is a high-throughput approach used to measure the expression levels of thousands of genes simultaneously, providing a comprehensive view of gene expression patterns and aiding in the understanding of complex biological phenomena.
