Biochemistry Term: Microarray
A microarray is a powerful tool in biochemistry and molecular biology that enables the simultaneous analysis of the expression levels of thousands of genes or the presence of numerous proteins in a biological sample.
It is a high-throughput technology that revolutionized the field of genomics and proteomics, providing researchers with a comprehensive and systematic approach to studying gene expression, identifying genetic variations, and investigating protein interactions on a large scale. Microarrays are particularly valuable in exploring the molecular underpinnings of various biological processes, diseases, and cellular responses.
In the context of gene expression analysis, a DNA microarray consists of a solid support, often a glass slide or a silicon chip, onto which thousands of different DNA probes are immobilized in an orderly array. These probes are short, single-stranded sequences that are complementary to specific genes of interest.
When fluorescently labeled RNA or cDNA derived from a biological sample is hybridized to the microarray, it allows for the simultaneous measurement of the expression levels of numerous genes. The intensity of the fluorescence signal at each spot on the microarray corresponds to the abundance of the corresponding mRNA in the sample, providing insights into the transcriptional activity of the genes.
Similarly, protein microarrays facilitate the large-scale analysis of protein interactions and activities. In a protein microarray, proteins or peptides are immobilized in an array format on a solid support. These arrays can be used to investigate protein-protein interactions, identify binding partners, and assess the specificity of antibodies. Protein microarrays are instrumental in studying signaling pathways, post-translational modifications, and the presence of specific proteins in complex biological samples.
Microarray technology has played a pivotal role in advancing our understanding of various biological processes, from development and disease to drug discovery. It has been widely used in cancer research to identify gene expression patterns associated with different cancer types and stages.
Microarrays have also been employed in pharmacogenomics to study how individual genetic variations influence drug responses, aiding in the development of personalized medicine approaches.
While microarrays have been widely used, newer technologies such as RNA sequencing (RNA-seq) and mass spectrometry-based proteomics have gained popularity due to their higher sensitivity and ability to provide more detailed information about gene expression and protein abundance.
Nevertheless, microarrays remain valuable tools, especially for large-scale screening studies and when a cost-effective and straightforward approach is needed for certain applications.
