XVI International Botanical Congess

We identified an asynaptic mutant of Arabidopsis (asy1) when screening the Feldmann lines for meiotic mutants. Cytological examination indicates asy1 undergoes a primary failure of synapsis during prophase I. Molecular cloning studies have enabled us to isolate the ASY1 gene and demonstrate that the mutant phenotype is due to a deletion of the promoter and 5' UTR. Sequence comparisons reveal that the protein encoded by ASY1 exhibits significant homology with the yeast synaptonemal complex protein Hop 1. Expression analysis reveals that ASY1 is expressed in wild type buds but is absent in asy1 mutant buds. Antisense experiments are currently in progress to confirm the meiotic function of ASY1. We have also identified a further Arabidopsis homologue of HOP1 that is currently being characterised.