The ability to regulate gene activity spatially and temporally is essential to investigate cell-type-specific gene function during development and in postembryonic processes and disease models. The Cre/ system has been widely used for performing cell and tissue-specific conditional analysis of gene function in zebrafish. However, simple and efficient methods for isolation of stable, Cre/ regulated zebrafish alleles are lacking.
View Article and Find Full Text PDFBackground: Retinoblastoma binding protein 4 (Rbbp4) is a component of transcription regulatory complexes that control cell cycle gene expression. Previous work indicated that Rbbp4 cooperates with the Rb tumor suppressor to block cell cycle entry. Here, we use genetic analysis to examine the interactions of Rbbp4, Rb, and Tp53 in zebrafish neural progenitor cell cycle regulation and survival.
View Article and Find Full Text PDFNon-host resistance (NHR), which protects all members of a plant species from non-adapted or non-host plant pathogens, is the most common form of plant immunity. NHR provides the most durable and robust form of broad-spectrum immunity against non-adaptive pathogens pathogenic to other crop species. In a mutant screen for loss of Arabidopsis (Arabidopsis thaliana) NHR against the soybean (Glycine max (L.
View Article and Find Full Text PDFResistance-nodulation-cell division multidrug efflux pumps are membrane proteins that catalyze the export of drugs and toxic compounds out of bacterial cells. Within the hydrophobe-amphiphile subfamily, these multidrug-resistant proteins form trimeric efflux pumps. The drug efflux process is energized by the influx of protons.
View Article and Find Full Text PDFFusarium virguliforme causes the serious disease sudden death syndrome (SDS) in soybean. Host resistance to this pathogen is partial and is encoded by a large number of quantitative trait loci, each conditioning small effects. Breeding SDS resistance is therefore challenging and identification of single-gene encoded novel resistance mechanisms is becoming a priority to fight this devastating this fungal pathogen.
View Article and Find Full Text PDFThe immutans (im) variegation mutant of Arabidopsis defines the gene for PTOX (plastid terminal oxidase), a versatile plastoquinol oxidase in chloroplast membranes. In this report we used im to gain insight into the function of PTOX in etioplasts of dark-grown seedlings. We discovered that PTOX helps control the redox state of the plastoquinone (PQ) pool in these organelles, and that it plays an essential role in etioplast metabolism by participating in the desaturation reactions of carotenogenesis and in one or more redox pathways mediated by PGR5 (PROTON GRADIENT REGULATION 5) and NDH (NAD(P)H dehydrogenase), both of which are central players in cyclic electron transport.
View Article and Find Full Text PDFThis paper reports a highly economical and accessible approach to generate different discrete relative humidity conditions in spatially separated wells of a modified multi-well plate for humidity assay of plant-pathogen interactions with good throughput. We demonstrated that a discrete humidity gradient could be formed within a few minutes and maintained over a period of a few days inside the device. The device consisted of a freeway channel in the top layer, multiple compartmented wells in the bottom layer, a water source, and a drying agent source.
View Article and Find Full Text PDFThe immutans (im) variegation mutation of Arabidopsis has green- and white- sectored leaves due to action of a nuclear recessive gene. IM codes for PTOX, a plastoquinol oxidase in plastid membranes. Previous studies have revealed that the green and white sectors develop into sources (green tissues) and sinks (white tissues) early in leaf development.
View Article and Find Full Text PDFThe immutans (im) variegation mutant of Arabidopsis has green and white-sectored leaves due to the absence of fully functional plastid terminal oxidase (PTOX), a plastoquinol oxidase in thylakoid membranes. PTOX appears to be at the nexus of a growing number of biochemical pathways in the plastid, including carotenoid biosynthesis, PSI cyclic electron flow, and chlororespiration. During the early steps of chloroplast biogenesis, PTOX serves as an alternate electron sink and is a prime determinant of the redox poise of the developing photosynthetic apparatus.
View Article and Find Full Text PDFThe immutans (im) variegation mutant of Arabidopsis thaliana is caused by an absence of PTOX, a plastid terminal oxidase bearing similarity to mitochondrial alternative oxidase (AOX). In an activation tagging screen for suppressors of im, we identified one suppression line caused by overexpression of AOX2. AOX2 rescued the im defect by replacing the activity of PTOX in the desaturation steps of carotenogenesis.
View Article and Find Full Text PDFA full-length cDNA clone of pigeonpea (Cajanus cajan L.) encoding cyclophilin (CcCYP) has been isolated from the cDNA library of plants subjected to drought stress. Amino acid sequence of CcCYP disclosed similarity with that of single-domain cytosolic cyclophilins of various organisms.
View Article and Find Full Text PDFA hybrid-proline-rich protein encoding gene (CcHyPRP) has been isolated and characterized, for the first time, from the subtracted cDNA library of pigeonpea (Cajanus cajan L.) plants subjected to drought stress. Functionality of CcHyPRP has been validated for abiotic stress tolerance using the heterologous yeast and Arabidopsis systems.
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