The family of ammonia and ammonium channel proteins comprises the Amt proteins, which are present in all three domains of life with the notable exception of vertebrates, and the homologous Rh proteins (Rh50 and Rh30) that have been described thus far only in eukaryotes. The existence of an RH50 gene in bacteria was first revealed by the genome sequencing of the ammonia-oxidizing bacterium Nitrosomonas europaea. Here we have used a phylogenetic approach to study the evolution of the N. europaea RH50 gene, and we show that this gene, probably as a component of an integron cassette, has been transferred to the N. europaea genome by horizontal gene transfer. In addition, by functionally characterizing the Rh50(Ne) protein and the corresponding knockout mutant, we determined that NeRh50 can mediate ammonium uptake. The RH50(Ne) gene may thus have replaced functionally the AMT gene, which is missing in the genome of N. europaea and may be regarded as a case of nonorthologous gene displacement.
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http://dx.doi.org/10.1128/JB.01089-07 | DOI Listing |
Parasit Vectors
July 2024
Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, 27695, USA.
Background: Lucilia cuprina (Wiedemann, 1830) (Diptera: Calliphoridae) is the main causative agent of flystrike of sheep in Australia and New Zealand. Female flies lay eggs in an open wound or natural orifice, and the developing larvae eat the host's tissues, a condition called myiasis. To improve our understanding of host-seeking behavior, we quantified gene expression in male and female antennae based on their behavior.
View Article and Find Full Text PDFJ Comp Neurol
January 2020
Genes Circuits Rhythmes et Neuropathologies, Plasticité du Cerveau, ESPCI Paris, CNRS, PSL University, Paris, France.
Rhesus glycoproteins (Rh50) have been shown to be ammonia transporters in many species from bacteria to human. They are involved in various physiological processes including acid excretion and pH regulation. Rh50 proteins can also provide a structural link between the cytoskeleton and the plasma membranes that maintain cellular integrity.
View Article and Find Full Text PDFPlant Physiol
January 2018
Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, D-82152 Planegg-Martinsried, Germany
DEAD-box RNA helicases (DBRHs) modulate RNA secondary structure, allowing RNA molecules to adopt the conformations required for interaction with their target proteins. RH50 is a chloroplast-located DBRH that colocalizes and is coexpressed with GUN1, a central factor in chloroplast-to-nucleus signaling. When combined with mutations that impair plastid gene expression (-, -, -, -, -, and -), and mutations evoke similar patterns of epistatic effects.
View Article and Find Full Text PDFBMC Evol Biol
January 2017
Dipartimento di Scienze Agro-alimentari, Ambientali e Animali (DI4A), Università di Udine, Via delle Scienze, 206-33100, Udine, Italy.
Background: Rh50 proteins belong to the family of ammonia permeases together with their Amt/MEP homologs. Ammonia permeases increase the permeability of NH/NH across cell membranes and are believed to be involved in excretion of toxic ammonia and in the maintenance of pH homeostasis. RH50 genes are widespread in eukaryotes but absent in land plants and fungi, and remarkably rare in prokaryotes.
View Article and Find Full Text PDFBiochem J
January 2015
†Departamento de Química Orgánica and UMYMFOR (CONICET-UBA), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina.
Dafachronic acids (DAs) are 3-keto cholestenoic acids bearing a carboxylic acid moiety at the end of the steroid side chain. These compounds interact with the DAF-12 receptor, a ligand-dependent transcription factor that acts as a molecular switch mediating the choice between arrest at diapause or progression to reproductive development and adult lifespan in different nematodes. Recently, we reported that the 27-nor-Δ4-DA was able to directly activate DAF-12 in a transactivation cell-based luciferase assay and rescued the Mig phenotype of daf-9(rh50) Caenorhabditis elegans mutants.
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