Jumping Gene Computational Approach - Multiobjective Optimization Methodology: A Jumping Gene Approach - page 34

A c activates D s
to transpose

D s transposes into C

A c D s C

A c D s

Figure 3.1
Transposition.of.Ds.in.a.chromosome.

The.class.II.JG.moves.directly.from.DNA.to.DNA.through.a.conservative.
mechanism..In.this.mechanism,.the.excision.of.the.donor.JG.is.followed.by.
its.reinsertion.elsewhere.in.the.genome.
A.class.III.JG.shifts.by.replicating.the.element.itself.and.inserting.the.copy.
into.a.new.site..This.operation.is.similar.to.that.of.a.class.I.JG,.but.it.does.not.
involve.transcription.via.an.RNA.intermediate.
According.to.the.effects.shown.in . Figure 3.2 , .the.three.classes.of.JGs.can.
be.simply.categorized.into.two.types:.cut-and-paste.JGs.and.copy-and-paste.
JGs. . Table 3.1 . tabulates.some.biological.examples.of.these.transposons.

DNA

JG

JG

(a) Conservative (cut-and-paste) transposition (class II JGs).

DNA JG

RNA JG

JG JG

(i) Retrotransposition (class I JGs).

Replication

DNA

JG

JG JG

(ii) Replicative transposition (class III JGs).
(b) Replicative (copy-and-paste) transposition (class I and III JGs).

Figure 3.2
Conservative.(cut-and-paste).transposition.and.replicative.(copy-and-paste).transposition.