Please what is heterologous expression in genes/ proteins?

Question

Please what is heterologous expression in genes/ proteins?

Answer 1

Heterologous - Of, or relating to, tissues or cytologic elements not normally found parts of the body of an individual, or that are derived from a different species.

Expression systems are tools to find out whether a particular gene produces mRNA and/or protein and whether the protein produced is functional or defective.

In principle, the gene construct to be studied is first transfected into a suitable host cell (bacterium, yeast, etc.) and its expression is then measured at the mRNA, protein or activity level. Such systems are needed especially when the expression level of the gene is low or when there are no specific probes for the gene to study its function, i.e. phenotype, in vivo.

Messenger ribonucleic acid (mRNA) is a molecule of RNA encoding a chemical "blueprint" for a protein product. mRNA is transcribed from a DNA template, and carries coding information to the sites of protein synthesis: the ribosomes. Here, the nucleic acid polymer is translated into a polymer of amino acids: a protein. In mRNA as in DNA, genetic information is encoded in the sequence of four nucleotides arranged into codons of three bases each. Each codon encodes for a specific amino acid, except the stop codons that terminate protein synthesis. This process requires two other types of RNA: transfer RNA (tRNA) mediates recognition of the codon and provides the corresponding amino acid, while ribosomal RNA (rRNA) is the central component of the ribosome's protein manufacturing machinery.