Bioinformatics for Big Omics Data: Molecular Biology 101

Raphael Gottardo
January 14, 2014

Outline

Cells and genomes
DNA, RNA, proteins
Central dogma of molecular biology

Cells and genomes

A T-cell

(Source: Wikipedia)

Cells and genomes

A Neuron

(Source: thetechjournal.com)

DNA

DNA (deoxyribose nucleic acid) contains the genetic instructions (A, G, C,T).
Double stranded (complementary) G-C, A-T

RNA

(Source: Wikipedia)

RNA (Ribonucleic acid) ressembles DNA
Single stranded, much shorter than DNA
Four bases A, C, G and U.

Protein

(Source: Wikipedia)

Organic compounds (amino acids joined by peptide bonds)
Essential to the structure and function of all living cells and viruses
20 possible amino acids (Lysine, Leucine, etc.)
Folding → Function

DNA, RNA and Proteins (and more)

How do they interact?
How do we get from DNA to proteins?

The Central Dogma

(Source: http://darwinview.blogspot.com/)

Certain pieces (genes) are transcribed
Gene ≈ piece of DNA coding for a protein
Gene → Protein (Gene is expressed)

Summary

DNA → RNA → Proteins
Can measure proteins directly but measuring
mRNA levels is easier
mRNA levels (gene expression levels) tell us something about proteins
How do we measure gene expression levels? Microarrays → Gene expression and more!
Understanding gene regulation requires a lot more than just gene expression: Chromatin, miRNA, alternative splicing, methylation, etc.