Figure 4.

Determination of the physical distance between p1 and p2 by CHEF gel analysis. Cells from plants of the indicated genotypes were protoplasted, embedded in agarose, and digested with NotI endonuclease. DNAs were separated by CHEF gel electrophoresis, transferred to membrane, and hybridized with genomic probe fragment 15 from the p1 gene (Figure 3). Left lane contains λDNA concatemers as size standards.