17 research outputs found
Identification and Functional Analysis of Light-Responsive Unique Genes and Gene Family Members in Rice
Functional redundancy limits detailed analysis of genes in many organisms. Here, we report a method to efficiently overcome this obstacle by combining gene expression data with analysis of gene-indexed mutants. Using a rice NSF45K oligo-microarray to compare 2-week-old light- and dark-grown rice leaf tissue, we identified 365 genes that showed significant 8-fold or greater induction in the light relative to dark conditions. We then screened collections of rice T-DNA insertional mutants to identify rice lines with mutations in the strongly light-induced genes. From this analysis, we identified 74 different lines comprising two independent mutant lines for each of 37 light-induced genes. This list was further refined by mining gene expression data to exclude genes that had potential functional redundancy due to co-expressed family members (12 genes) and genes that had inconsistent light responses across other publicly available microarray datasets (five genes). We next characterized the phenotypes of rice lines carrying mutations in ten of the remaining candidate genes and then carried out co-expression analysis associated with these genes. This analysis effectively provided candidate functions for two genes of previously unknown function and for one gene not directly linked to the tested biochemical pathways. These data demonstrate the efficiency of combining gene family-based expression profiles with analyses of insertional mutants to identify novel genes and their functions, even among members of multi-gene families
The Drosophila melanogaster host model
The deleterious and sometimes fatal outcomes of bacterial infectious diseases are the net result of the interactions between the pathogen and the host, and the genetically tractable fruit fly, Drosophila melanogaster, has emerged as a valuable tool for modeling the pathogen–host interactions of a wide variety of bacteria. These studies have revealed that there is a remarkable conservation of bacterial pathogenesis and host defence mechanisms between higher host organisms and Drosophila. This review presents an in-depth discussion of the Drosophila immune response, the Drosophila killing model, and the use of the model to examine bacterial–host interactions. The recent introduction of the Drosophila model into the oral microbiology field is discussed, specifically the use of the model to examine Porphyromonas gingivalis–host interactions, and finally the potential uses of this powerful model system to further elucidate oral bacterial-host interactions are addressed
Photoprotective Mechanisms: Carotenoids
Environmental light can frequently be detrimental to the photosynthetic
machinery of plants. This chapter provides an up-to-date overview of the targets of
the photo-oxidative damage caused by light and the multiple functions of photosynthetic
carotenoids that minimize it. Recently acquired knowledge on the localisation
and distribution of carotenoids in the photosynthetic apparatus of plants is
presented. Mechanisms that control the light harvesting process in the photosynthetic
antenna of higher plants, via protective energy dissipation, are compared and
discussed. The role of functional genomics approaches to the study of the multiple
functions of carotenoids are highlighted. The significance of carotenoid structure
and the physico-chemical properties that enable fine control over the photosynthetic
light harvesting processes are analysed and discussed in order to explain the variety
of their types