9.6 Central Dogma Genetics

Central Dogma of Genetics

Describes the flow of genetic information during gene expression

DNA → RNA → Protein

Sequence of information flow from gene storage to functional protein

Direction of genetic information flow

DNA to RNA to protein and does not normally move backwards

Template principle

Each polymer acts as a template to build the next polymer

Reverse transcription

Process where RNA is used to make DNA using the enzyme reverse transcriptase

Exception to central dogma

Occurs in some viruses

RNA World Hypothesis

Theory that self-replicating RNA molecules were the earliest form of life

RNA as early genetic material

RNA could store genetic information like DNA

RNA catalytic ability

RNA can catalyze chemical reactions like proteins

Early life idea

RNA likely preceded DNA and proteins in evolution

Why DNA evolved

DNA is more stable due to deoxyribose lacking an extra hydroxyl group

RNA instability

RNA is more reactive and less stable than DNA

Why proteins evolved

Proteins are more reactive and efficient catalysts than RN