Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: 11/16/2004
Publication Date: 1/14/2005
Citation: Singh, M., Burson, B.L., Finlayson, S. 2005. Comparative gene expression in the ovules of sexual and apomictic buffelgrass (Pennisetum ciliare) [abstract]. Plant and Animal Genome XIII Conference. p. 253.
Technical Abstract: Apomixis, an asexual method of reproduction through seeds with the absence of meiosis and fertilization, holds great potential for revolutionizing plant breeding and hybrid seed production. Buffelgrass, an apomictic forage grass, has well characterized apomictic, facultative and sexual accessions to study apomictic development. To study comparative gene expression during female gametophyte development in the sexual and apomictic genotypes of buffelgrass, subtracted cDNA libraries were constructed utilizing the techniques of Suppression Subtractive Hybridization (SSH). These subtractive libraries represented the megasprogenesis and megagametogenesis stages of ovule development. The subtractions performed were apomictic versis sexual and vice versa and also ovary versus leaf tissue. A high throughput method for screening these libraries was developed using a combination of macroarrays and RNA blot analysis. Several ovary-specific clones have been identified from the megasporogenesis and megagametogenesis stages of development. The majority of these cDNA clones are expressed at similar levels in the apomictic and sexual ovaries. However, some of these cDNA clones exhibit preferential expression in the apomictic and sexual ovaries. To determine the cell-specificity of these clones, in situ hybridizations are being performed. While some of these clones have sequence similarity to known genes or ESTs, others do not show any homology with known sequences and may represent novel ovary/ovule specific genes.