<%@LANGUAGE="JAVASCRIPT" CODEPAGE="1252"%> Holliday Model

Genetic 342 A&B

Kenneth G Wilson

Professory of Botany

The Molecular Basis of Crossing Over

 

The Initiation of C/O is two adjacent breaks in non-sister chromatids

nicks
Repair leads to a Holliday Junction holliday jnct
Cross migration leads to a Heteroduplex region
Redrawing for clarity gives the structure redraw Holliday
The circle outlines the direction of rotation with no change in the DNA/Holliday Junction intermed
This structures shows that we have an X that can be removed by breaking in the horizontal or vertical direction. Think of it as cutting with scissors. split

The two possible outcomes.

  1. Results in no change or really no crossover
  2. The second results in the crossover and results in crossover gametes

 

 

 

 

Summary

 results

 

oliver

This is our friend Oliver the parrotlet,

Oliver is a true parrot,

the smallest in the world.