Overview of Protein Synthesis and RNA Interference

Protein Synthesis

Process of creating proteins from DNA instructions.

Transcription

Conversion of DNA to RNA in the nucleus.

Translation

Conversion of mRNA to protein in the cytoplasm.

RNA Polymerase

Enzyme that synthesizes RNA from DNA template.

Promoter

DNA sequence where RNA polymerase binds to start transcription.

Helicase

Enzyme that unwinds DNA strands during transcription.

mRNA

Messenger RNA that carries genetic information.

tRNA

Transfer RNA that brings amino acids to ribosomes.

Ribosome

Cellular structure where protein synthesis occurs.

Codon

Three-nucleotide sequence on mRNA coding for an amino acid.

Anticodon

Three-nucleotide sequence on tRNA complementary to mRNA codon.

Peptide Bond

Linkage between amino acids in a protein chain.

Stop Codon

Signals termination of translation; does not code for amino acid.

Start Codon

AUG codon that initiates translation, coding for methionine.

Introns

Non-coding segments of RNA removed during processing.

Exons

Coding segments of RNA that remain after processing.

RNA Interference (RNAi)

Regulation of gene expression by degrading mRNA.

Dicer

Enzyme that cleaves double-stranded RNA into siRNA.

RISC

RNA-induced silencing complex that uses siRNA for mRNA targeting.

Central Dogma

Framework describing flow of genetic information: DNA → RNA → Protein.

Genetic Code

Sequence of nitrogen bases that determines protein synthesis.

Mutation

Change in DNA sequence affecting transcription and protein production.

Polypeptide Chain

Sequence of amino acids linked by peptide bonds.

Protein Folding

Process where polypeptide achieves its functional three-dimensional shape.

Hydrophobic Amino Acids

Nonpolar amino acids that avoid water in protein structure.

Hydrophilic Amino Acids

Polar amino acids that interact with water in protein structure.

Disulfide Bridges

Covalent bonds that stabilize protein structure.

Homeostasis

Maintenance of stable internal conditions in an organism.

Gene Regulation

Control of gene expression levels in response to cellular needs.