cDNAvá

cDNA is a complementary DNA molecule synthesized from an RNA template. This process, known as reverse transcription, is carried out by an enzyme called reverse transcriptase. Naturally occurring in retroviruses, reverse transcriptase can also be isolated and used in molecular biology laboratories. The RNA used as a template for cDNA synthesis is typically messenger RNA (mRNA), which carries the genetic code from DNA to ribosomes for protein production.

The advantage of converting mRNA to cDNA is that DNA is more stable than RNA and can be easily amplified, cloned, and sequenced. This makes cDNA a valuable tool for studying gene expression. By isolating mRNA from a cell or tissue at a specific time, researchers can create a cDNA library representing all the genes actively being transcribed. This library can then be used to identify which genes are turned on or off in different conditions, or to isolate specific genes of interest. Furthermore, since mRNA contains only exons (coding regions of a gene), the resulting cDNA lacks introns (non-coding regions) that are present in genomic DNA. This simplification can be beneficial for certain applications, such as expressing eukaryotic genes in prokaryotic systems.