characteristics of human genome Flashcards
(15 cards)
annotation
identifying the genes present after sequencing a genome
what indicates the presence of a protein coding gene
open reading frame
generating ESTs
mature mRNA>cDNA with reverse transcriptase>insert into cloning vector>short sequences are read from either the 5’ or 3’ end of the insert
lncRNAs
poorly conserved between species
regulate gene expression
correlation between number of lncRNAs and organismal complexity
high flexibility to sequence changes
miRNAs
22 nucleotides
bind to 3’ UTR of mRNA
highly conserved
transposable elements
highly repetitive
can change their position and multiply within the genome
promote evolution
4 classes of transposable elements
LINE
SINE
LTR
DNA transposons
retrotransposons
have the ability to self amplify and spread throughout genome
LINEs
long interspersed nuclear elements
type of retrotransposon
LINE 1 (most common) LINE 2 LINE 3
LINE 1
gene encodes enzymes capable of copying and pasting the gene itself
endonuclease and reverse transcriptase components
long terminal repeats (LTRs)
associated with endogenous retroviral sequences
ERVs
sequences from viruses that have infected the human germline at some point in our ancestry that have maintained transposon activity
short interspersed nuclear elements (SINEs) example
members of Alu repeat family
only in primates
actively transposing
Don’t encode any of the enzymes involved in retro transposition. They hijack machinery from the line 1 genes
mitochondrial genome
circular DNA resembling a plasmid
17kb
encodes 37 genes for mitochondrial function
evolution of mitochondrial genome
early ancestors of eukaryotes engulfed bacteria and retained them in the cytoplasm
vesicle membrane became outer mitochondrial membrane
bacterial membrane became inner mitochondrial membrane
