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.
