Plant & Animal Genomes XIII Conference Plant & Animal Genomes XIII ConferenceJanuary 15-19, 2005
Town & Country Convention Center
San Diego, CA
Stefano Capomaccio , Daniele Rosellini , Fabio Veronesi
Knowledge on reproduction control in plants has many applications, from seed production to breeding practice. Several sporophytic mutations influencing both male and female meiosis have been described, but there are only two reports of mutations determining the block of female meiosis only (Siddiqi et al. 2000, Development 127: 197-207; Motamayor et al. 2000, Sex. Plant Reprod. 12: 209-218), involving the same gene. An alfalfa female sterile mutant was previously cytologically and phenotipically characterized (Rosellini et al. 2003, Sexual Plant Reprod. 15:271-279), revealing a female-specific arrest of sporogenesis associated with ectopic, massive callose deposition within the nucellus.
The goal of this study is to isolate and characterize genes involved in megasporogenesis and female sterility in this mutant.
The cDNA-AFLP technique was employed to isolate genes differentially expressed between wild type and female-sterile full-sib alfalfa plants. Ninety six ESTs were generated, and most of them published (GenBank CB165074--->CB165159). BLAST analysis have revealed similarities with genes involved in the cell cycle, development and callose metabolism.
Four clones were selected to proceed with further studies: CB165076 similar to Arabidopsis thaliana eucaryotic initiation translation factor eIF4G III; CB165091 similar to a soybean 1,3 beta-glucanase; CB165105, similar to the A. thaliana transcription factor SCARECROW gene regulator; and CB165125 similar to an A. thaliana MAPKKK.
Full length mRNA sequences were obtained using RACE technique. RT-PCR was performed to confirm differential expression during flower development using the 18s rRNA as control gene. In situ hybridization is carried out to reveal the sites of expression of the selected genes.