Figure 1.—

Association of aberrant SRK transcript processing with self-fertility in A. thaliana–lyrata hybrids and allotetraploid derivatives. Gel blots of stigma poly(A)+ RNA were hybridized with a probe derived from exon 1 of A. lyrata SRKa as previously described (Kusaba et al. 2001). Al, A. lyrata; H1 and H2, first-generation hybrids; BC, a first-generation plant from a backcross of H2 to A. lyrata; allo1, allo2, and allo3, three consecutive allotetraploid generations. The 3- and 1.6-kb transcripts typically produced by SRK genes are indicated. Note the 4-kb aberrant SRKa transcripts produced by stigmas of F₁ hybrids (asterisks) and allotetraploid derivatives (arrow).