Cytological Characterization of Arabidopsis arenosa Polyploids by SIM

Arabidopsis arenosa has recently become established as a model organism for investigating how meiosis has evolved to overcome the meiotic challenges faced by newly formed autotetraploids. Here, we describe a protocol for the preparation of spread, immunolabeled prophase I chromosomes from established A. arenosa autotetraploids for imaging with three-dimensional structured illumination microscopy (3D-SIM). This technique allows us to dissect the unique synaptic behavior in A. arenosa and identify synaptic partner switch sites that are unresolvable with conventional widefield microscopy.