Analysis of the functional relationships of gametocidal genes

We have recently produced EMS-induced knock-out mutations at the Gc2 locus that were derived from Ae. sharonensis. Our data suggest that the Gc2 mutant is a knock-out of the gene encoding for the breaking agent. For analyzing the interactions of the Gc2 mutants with other Gc genes from different Aegilops species, we have crossed stocks with functional and mutant Gc2 genes with stocks having Gc genes from Ae. speltoides (T2B- 2S, Gc1), Ae. cylindrica (DA2Cc, GcAe.cyl.), Ae. triuncialis (DtA3C t L, Gc3), and Ae. geniculata (DA4M g , GcAe.genic.). If the mode of action of Gc1, Gc3, GcAe.cyl., and GcAe.genic. is similar to that of Gc2, the introduction of a mutant Gc2 allele that lacks the factor for the breaking agent and only encodes for the protecting agent might restore the fertility in these plants. The presented data show that in none of the cross combinations analyzed does the introduction of a Gc2 mutant allele rescue plant fertility suggesting that their modes-of- action are different.