A Mini Review on Gene Expression

Abstract

A DNA molecule is more than just a long, monotonous string of nucleotides. Instead, it is divided into functional units known as genes. All cells use information encoded in their DNA to control or regulate protein synthesis. Gene refers to the process of turning on a to produce RNA and protein. All known life— eukaryotes (including multicellular organisms), prokaryotes (bacteria and archaea), and viruses—use to generate the macromolecular machinery for life. Gene is the most fundamental level at which the genotype gives rise to t in genetics. The regulation of is a highly complex process. Strictly speaking, gene expression refers to the process of a being activated until a mature protein is found in its corresponding compartment to perform its function and contribute to the of a cell's phenotype. The purpose of the studies is to detect and quantify messenger RNA (mRNA) levels of a specific gene. The rapid activation of in response to stimuli is largely controlled by RNA polymerase II-dependent transcription. Gene microarrays are being used to study RNA and may be used to derive profiles/signatures associated with tumour and normal tissue radio response. The events that occur during the transcription cycle in eukaryotes that are important for the rapid and specific activation of in response to external stimuli are discussed in this review.