#Genetics#Molecular Biology#DNA
What is the central dogma of molecular biology?
TL;DR Summary: The central dogma of molecular biology is the process by which the instructions in DNA are converted into a functional product, summarized as 'DNA makes RNA, and RNA makes protein.'
What is the central dogma of molecular biology?
First proposed by Francis Crick in 1958, the central dogma of molecular biology provides a framework for understanding the flow of genetic information within a biological system. It states that genetic information is transferred from nucleic acids (DNA and RNA) to proteins.
The Three Main Stages
The central dogma is generally broken down into three major sequential processes:
- Replication: The process by which DNA is copied to ensure that every new cell gets a complete set of genetic instructions. This does not flow into protein synthesis directly, but it is essential for perpetuating the code.
- Transcription: The process where the genetic code in DNA is copied into a messenger RNA (mRNA) molecule. This happens in the nucleus of eukaryotic cells.
- Translation: The process where the mRNA molecule is decoded by ribosomes to produce a specific amino acid chain, which eventually folds into an active protein. This takes place in the cytoplasm.
Refinements and Exceptions
While the simplified flow is DNA $\rightarrow$ RNA $\rightarrow$ Protein, biology is more complex. Reverse transcription (where RNA is converted back into DNA, utilized by retroviruses like HIV) and non-coding RNAs that perform regulatory functions without becoming proteins have expanded our understanding of molecular information flow.