Role of Proteins in the Body

Introduction to Proteins

Proteins are molecules composed of amino acids and coded for by genes.
They are essential for forming tissues and play pivotal roles in biological processes.
Functions include catalyzing reactions, transporting molecules like oxygen, maintaining immune health, and cell communication.

Genes: Segments of DNA that hold instructions for creating unique proteins.
Stages of Protein Synthesis:
1. Transcription: Formation of mRNA from DNA, carrying protein-making information.
2. Translation: mRNA moves to cytoplasm; ribosomes read and assemble proteins using a sequence of bases (codons).
  - Codons are 3-letter nucleotide sequences coding for amino acids (e.g., TTT codes for lysine).
  - 64 possible codons exist; however, only 20 amino acids are required for all proteins.
Protein synthesis is influenced by environmental factors like nutrition, temperature, stress, oxygen levels, and chemical exposure.

Enzymes: Facilitate biochemical reactions (e.g., pepsin in digestion).
Antibodies: Produced by the immune system to combat foreign substances and infections.
DNA-associated Proteins: Regulate chromosome structure and gene expression (e.g., histones, cohesin).
Contractile Proteins: Aid muscle contraction and movement (e.g., actin, myosin).
Structural Proteins: Provide body support (e.g., collagen, elastin).
Hormone Proteins: Coordinate bodily functions (e.g., insulin for glucose regulation).
Transport Proteins: Move molecules across the body (e.g., hemoglobin for oxygen transport).

Some proteins have multiple roles, such as cohesin proteins which are involved in both chromosome regulation and gene expression during development.
Dr. Julia Horsfield's research at the University of Otago explores cohesin proteins' dual roles, focusing on gene expression impacts and related diseases.

Molecule: Two or more atoms bonded together.
Amino Acid: Building blocks of proteins.
Gene: DNA segment determining protein creation and individual traits.
Catalysis: Speeding up chemical reactions.
Immune System: Defense against foreign invaders.
DNA: Molecule containing organism development instructions.
mRNA (Messenger RNA): Template for protein synthesis formed during transcription.
Codon: mRNA unit composed of three nucleotides coding for amino acids.
Enzyme: Protein acting as a catalyst in biochemical reactions.
Gene Expression: Use of a gene to make a protein.

Visit the Learn Genetics website for animated tours on DNA, genes, and proteins.