Chapter 14 Flashcards
A type of genetic recombination that occurs only at specific sequences
site-specific recombination
A transposon that moves via an RNA intermediate that is converted back to DNA by reverse transcriptase.
transposon and transposable element
Bacteriophage infection in which the DNA is incorporated into the host chromosome or as an autonomously replicating plasmid with most of its genes repressed
lysogenic pathway
Parasitic bacteriophage infection in which the DNA is replicated and packaged into phage heads, and the host cell is destroyed by lysis to disperse the progeny. Compare lysogenic pathway
lytic pathway
A bacteriophage-encoded site-specific recombination system that promotes circularization of the phage P1 genome and aids in proper segregation at cell division of phage plasmids in the lysogenic state.
Cre-lox
The expression of alternative primary cell surface antigens used by some pathogenic bacteria and parasitic protists as a means of eluding a host’s immune system.
phase variation
The location on a chromosome of a transposon before it moves to a target site.
donor site
The location on a chromosome where a transposon inserts itself
target site
Transposon-encoded enzymes that catalyze the reactions required for the transposon to excise itself from the donor site and insert itself into the target site. These reactions typically include hydrolysis of a specific phosphodiester bond and transesterification involving attack of the liberated 3′ hydroxyl on another phosphodiester bond.
transposase
The DNA is
excised from its donor site, then completely
inserted in the target site.
cut and paste mechanism
The transposon is
linked to the target before it is excised.
Replication then occurs, resulting in two
copies of the transposable element, one at the donor and one at the target site
replicative transposition
an RNA intermediate is
used to create a new transposon via reverse
transcription which is then copied to the
target site
Transposition with RNA intermediate
A transposon that moves via an RNA intermediate that is converted back to DNA by reverse transcriptase.
retrotransposon (retrotransposable element)
An RNA-directed DNA polymerase in retroviruses; capable of making DNA complementary to an RNA.
reverse transcriptase
A retrotransposon that moves via a double-stranded cDNA copy of its mRNA transcript. The cDNA inserts itself into the target site in a reaction catalyzed by a recombinase or integrase.
extrachromosomally primed (EP) retrotransposon
An enzyme that catalyzes the insertion of a retrovirus or retrotransposon into its target site.
integrase
A specific base sequence at either end of a transposable segment of DNA.
insertion sequence
A transposon that consists of two insertion elements flanking one or more genes not required for transposition, such as antibiotic-resistance genes
composite transposon
A viruslike transposon with a large genome including genes not required for transposition
complex transposon
Another elegant example of SSR that facilitates DNA replication is the
2 micro plasmid
An RNA virus containing a reverse transcriptase.
retrovirus
A duplex DNA with one strand identical to a specific mRNA (with T residues generally substituting for the U residues in the mRNA), used in DNA cloning; usually made by reverse transcriptase
complementary DNA (cDNA)
A protein secondary structure in which the amino acid residues D, D, and E (two aspartate residues and a glutamine residue) form the catalytic core in the active site of phosphoryltransferase enzymes such as integrases and transposases
DDE motif
