Isolation and characterization of 4 gametophytic male sterile mutants in Arabidopsis thaliana

Abstract

In flowering plants, male fertility depends on the formation and development of normal male gametophytes or pollen grains. However, little is known about the molecular mechanisms that regulate the processes. Here, we report the identification of four novel independent Arabidopsis gametophytic male sterile mutants, apam1, apam2, apam3 and apam4 (Arabidopsis pollen abortion mutant). The four mutants that were generated by the insertions of gene-and enhancer-trap Ds transposon elements were defective in pollen development. Genetic analysis results showed that all four mutations resulted in the loss of male gametophytic function, but did not affect female gametophytic function, and the Ds elements were linked to the mutations tightly in all four mutants. Localization of the Ds insertion sites by thermal asymmetric interlaced PCR (TAIL-PCR) showed that the Ds elements were inserted in four different loci distributed on three chromosomes, chromosomes II, III and V. In summary, the apam4 is allelic to AHA3, while the other three were located in places where there are no genes that have been known to be involved in pollen development, suggesting that they are novel mutations involved in pollen development.