Introduction to molecular biology….ppt

Introduction to molecular biology… (…in one hour!!) Stephen Edwards Overview Overview of the cell Different sizes/functions Organised structure Bacterial genetics are different Eukaryotic cell DNA Contained in the nucleus Arranged in 22 chromosomes, plus two sex chromosomes Two copies of each 99.9% identical to other humans, 98% to chimp! Around 2m DNA, enough to travel to sun and back 600 times! Therefore, very tightly packed DNA function Carries the blueprint for life Duplication for new cells Make proteins for biological functions: Gene structure Genes must have: Exons Start site Control region mRNA DNA is grouped into threes (codons) AGTTTTGGGCCCAAA Start and stop codons mRNA is then modified… …and travels out of the nucleus mRNA splicing Alternative splicing Translation Uses mRNA as template to make proteins Occurs in ribosomes One codon corresponds to one amino acid Proteins Huge proportion of cell (after water) Many functions: Structure (e.g. collagen in bone) Enzymes Transmembrane receptors Hormones Four levels of structure Protein structure Protein interactions Proteins can form interations: Proteins (complexes, oligomers) mRNA DNA Proteins can bind to each other depending on their relative charges and structures Gene expression regulation Common terminology Genome/proteome Genotype/phenotype Pseudogene Novel protein/gene Putative gene Locus/Allele/Chromosome region Dominant/Recessive Homologous Symbol cDNA Motif Dalton (Da or kDa) Common abbreviations EST expressed sequence tag SNP single nucleotide polymorphism ORF open reading frame UTR untranscribed region Experimental techniques Cut, change, knockout genes Transgenics Sequence genes and proteins Over-express proteins Microarrays Future of molecular biology Personalised medicine Target-specific drugs (e.g. adipose tissue) Gene therapy Comparative genomics References Molecular biology information ‘Biology’, Campbell and Reece (6th Ed.), Very readable general biology textbook www.ebi.ac.uk/2can, go