Search results for "Genetic Complementation Test"
showing 10 items of 33 documents
The Arabidopsis COPT6 Transport Protein Functions in Copper Distribution Under Copper-Deficient Conditions
2013
Copper (Cu), an essential redox active cofactor, participates in fundamental biological processes, but it becomes highly cytotoxic when present in excess. Therefore, living organisms have established suitable mechanisms to balance cellular and systemic Cu levels. An important strategy to maintain Cu homeostasis consists of regulating uptake and mobilization via the conserved family of CTR/COPT Cu transport proteins. In the model plant Arabidopsis thaliana, COPT1 protein mediates root Cu acquisition, whereas COPT5 protein functions in Cu mobilization from intracellular storage organelles. The function of these transporters becomes critical when environmental Cu bioavailability diminishes. Ho…
Functional characterization of the plastidial 3-phosphoglycerate dehydrogenase family in Arabidopsis.
2013
This work contributes to unraveling the role of the phosphorylated pathway of serine (Ser) biosynthesis in Arabidopsis (Arabidopsis thaliana) by functionally characterizing genes coding for the first enzyme of this pathway, 3-phosphoglycerate dehydrogenase (PGDH). We identified two Arabidopsis plastid-localized PGDH genes (3-PGDH and EMBRYO SAC DEVELOPMENT ARREST9 [EDA9]) with a high percentage of amino acid identity with a previously identified PGDH. All three genes displayed a different expression pattern indicating that they are not functionally redundant. pgdh and 3-pgdh mutants presented no drastic visual phenotypes, but eda9 displayed delayed embryo development, leading to aborted emb…
A critical role of plastidial glycolytic Glyceraldehyde-3-Phosphate Dehydrogenase in the control of plant metabolism and development
2009
3 páginas.
Diverse cell surface protein ectodomains are shed by a system sensitive to metalloprotease inhibitors.
1996
The extracellular domains of a diverse group of membrane proteins are shed in response to protein kinase C activators such as phorbol 12-myristate 13-acetate (PMA). The lack of sequence similarity in the cleavage sites suggests the involvement of many proteases of diverse specificity in this process. However, a mutant Chinese hamster ovary cell line recently isolated for being defective in PMA-activated shedding of the membrane-anchored growth factor transforming growth factor alpha precursor (proTGF-alpha) is concomitantly defective in the shedding of many other unrelated membrane proteins. Here we show that independent mutagenesis and selection experiments yield shedding mutants having th…
Complementation of Saccharomyces cerevisiae mutationsin genes involved in translation and protein folding (EFB1 and SSB1)with Candida albicans cloned…
2000
We have demonstrated that the expression of Candida albicans genes involved in translation and protein folding (EFB1 and SSB1) complements the phenotype of Saccharomyces cerevisiae mutants. The elongation factor 1beta (EF-1beta) is essential for growth and efb1 S. cerevisiae null mutant cells are not viable; however, viable haploid cells, carrying the disrupted chromosomal allele of the S. cerevisiae EFB1 gene and pEFB1, were isolated upon sporulation of a diploid strain which was heterozygous at the EFB1 locus and transformed with pEFB1 (a pEMBLYe23 derivative plasmid containing an 8-kb DNA fragment from the C. albicans genome which contains the EFB1 gene). This indicates that the C. albic…
Molecular cloning of the RPS0 gene from Candida tropicalis.
2001
The Saccharomyces cerevisiae RPS0 A and B genes encode proteins essential for maturation of the 40S ribosomal subunit precursors. We have isolated a homologue of the RPS0 gene from Candida tropicalis, which we named CtRPS0. The C. tropicalisRPS0 encodes a protein of 261 amino acid residues with a predicted molecular weight of 28.65 kDa and an isoelectric point of 4.79. CtRps0p displays significant amino acid sequence homology with Rps0p from C. albicans, S. cerevisiae, Neurospora crassa, Schizosaccharomyces pombe, Pneumocystis carinii and higher organisms, such as human, mouse and rat. CtRPS0 on a high copy number vector can complement the lethal phenotype linked to the disruption of both R…
The Histidinol Phosphate Phosphatase Involved in Histidine Biosynthetic Pathway Is Encoded by SCO5208 (hisN) in Streptomyces coelicolor A3(2)
2008
Through the screening of a Streptomyces coelicolor genomic library, carried out in a histidinol phosphate phosphatase (HolPase) deficient strain, SCO5208 was identified as the last unknown gene involved in histidine biosynthesis. SCO5208 is a phosphatase, and it can restore the growth in minimal medium in this HolPase deficient strain when cloned in a high or low copy number vector. Moreover, it shares sequence homology with other HolPases recently identified in Actinobacteria. During this work a second phosphatase, SCO2771, sharing no homologies with SCO5208 and all so far described phosphatases was identified. It can complement HolPase activity mutation only at high copy number. Sequence …
Host-Nonspecific Iron Acquisition Systems and Virulence in the Zoonotic Serovar of Vibrio vulnificus
2014
ABSTRACT The zoonotic serovar of Vibrio vulnificus (known as biotype 2 serovar E) is the etiological agent of human and fish vibriosis. The aim of the present work was to discover the role of the vulnibactin- and hemin-dependent iron acquisition systems in the pathogenicity of this zoonotic serovar under the hypothesis that both are host-nonspecific virulence factors. To this end, we selected three genes for three outer membrane receptors ( vuuA , a receptor for ferric vulnibactin, and hupA and hutR , two hemin receptors), obtained single and multiple mutants as well as complemented strains, and tested them in a series of in vitro and in vivo assays, using eels and mice as animal models. Th…
Role of tir and intimin in the virulence of rabbit enteropathogenic Escherichia coli serotype O103:H2.
2000
ABSTRACT Attaching and effacing (A/E) rabbit enteropathogenic Escherichia coli (REPEC) strains belonging to serogroup O103 are an important cause of diarrhea in weaned rabbits. Like human EPEC strains, they possess the locus of enterocyte effacement clustering the genes involved in the formation of the A/E lesions. In addition, pathogenic REPEC O103 strains produce an Esp-dependent but Eae (intimin)-independent alteration of the host cell cytoskeleton characterized by the formation of focal adhesion complexes and the reorganization of the actin cytoskeleton into bundles of stress fibers. To investigate the role of intimin and its translocated coreceptor (Tir) in the pathogenicity of REPEC, …
Acyl-homoserine lactone production is more common among plant-associated Pseudomonas spp. than among soilborne Pseudomonas spp.
2001
ABSTRACT A total of 137 soilborne and plant-associated bacterial strains belonging to different Pseudomonas species were tested for their ability to synthesize N -acyl-homoserine lactones (NAHL). Fifty-four strains synthesized NAHL. Interestingly, NAHL production appears to be more common among plant-associated than among soilborne Pseudomonas spp. Indeed, 40% of the analyzed Pseudomonas syringae strains produced NAHL which were identified most often as the short-chain NAHL, N -hexanoyl- l -homoserine lactone, N -(3-oxo-hexanoyl)-homoserine lactone, and N -(3-oxo-octanoyl)- l -homoserine lactone (no absolute correlation between genomospecies of P. syringae and their ability to produce NAHL …