Genomes Flashcards
Andrew Holland Lecture 1
What are genes?
hereditary characteristics
What is a genome?
how genes are arranged
T/F. Prokaryotic genome size varies according to biological complexity
True, generally, prokaryotes accumulate more genes the more diverse their environment is, and tend to be smaller in a niche env
5 E. coli genome features
supercoiled (circular), no introns, 11% intergenic DNa, little repetitive DNA, one replication origin
what is an operon?
Unit of genes that are transcribed together.
3 ways for Bacterial Horizontal Gene Transfer
Tranformation, Transduction, conjugation
5 Nuclear Genome Features
linear, chromosome number varies, packaged DNA, discontinuous genes, varying gene density
3 types of repetitive DNA
Satellite DNA - centromeric DNA
Minisatellites (10-60 bp) - Telomeric DNA
Microsatellites (2-6 bp)
How do you get repetitive DNA?
recombination or replication slippage
4 Classes of Transposable Elements
SINE
LINE
LTR retroelements
DNA Transposons
Know these at end of lecture
5 types of non-coding RNA and functions
rRNA - translation snRNA (splicing) snoRNA - chemical modification of rRNA siRNA, miRNA - RNA interference piRNA - silence retrotransposons
How do we know non-coding RNAs are important?
8-15% of human genome is under functional constraint, but only 1.5% is protein coding
T/F. Regions of the nucleus are preferentially occupied by particular chromosomes
True
Technique: Chromosome Conformation Capture
Crosslink DNA, cut with restriction enzyme, fill ends with biotin marker, ligate, shear DNA and pulldown w/ streptavidin, sequence
Will see TADs
What are TADs?
Topologically associated domains. Functional domains and posses genes with similar expression patterns. Conserved across cell types and related species.
Two way genes can be organized
Developmental onset
Spatial expression patterns
