Single and Double Knockouts of the Genes for Photosystem I Subunits G, K, and H of Arabidopsis

Photosystem I (PSI) of higher plants contains 18 subunits. Using Arabidopsis En insertion lines, we have isolated knockout alleles of the genes psaG, psaH2, and psaK, which code for PSI-G, -H, and -K. In the mutants psak-1 and psag-1.4, complete loss of PSI-K and -G, respectively, was confirmed, whereas the residual H level in psah2-1.4 is due to a second gene encoding PSI-H, psaH1. Double mutants, lacking PSI-G, and also -K, or a fraction of -H, together with the three single mutants were characterized for their growth phenotypes and PSI polypeptide composition. In general, the loss of each subunit has secondary, in some cases additive, effects on the abundance of other PSI polypeptides, such as D, E, H, L, N, and the light-harvesting complex I proteins Lhca2 and 3. In the G-less mutant psag-1.4, the variation in PSI composition suggests that PSI-G stabilizes the PSI-core. Levels of light-harvesting complex I proteins in plants, which lack simultaneously PSI-G and -K, indicate that PSI subunits other than G and K can also bind Lhca2 and 3. In the same single and double mutants, psag-1.4, psak-1, psah2-1.4, psag-1.4/psah2-1.4, and psag-1.4/psak-1 photosynthetic electron flow and excitation energy quenching were analyzed to address the roles of the various subunits in P700 reduction (mediated by PSI-F and -N) and oxidation (PSI-E), and state transitions (PSI-H). Based on the results, we also suggest for PSI-K a role in state transitions

Gingival Taste Bud Papillae Associated with Retromolar Salivary Gland

Taste in the gustatory system allows to distinguish between safe and harmful food, and to gauge its nutritional value. Digestive enzymes in saliva begin to dissolve food into base chemicals that are detected by taste buds containing three different cell types involved in the perception of the five basic tastes. Von Ebner\u27s glands, found adjacent to the moats surrounding the circumvallate (CV) and foliate papillae, are exocrine salivary glands that secrete digestive enzymes and presumably flush material out of the papillae. Recently, we rediscovered and characterized anatomically and molecularly a chemosensory structure in the mouse oral cavity consisting of unorganized taste buds associated with ducts and a gland at the rear of the mandible, distal to the last molar and anterior to the ascending ramus. These taste buds appear to be the same ones first described by Iida in 1983, Miller in 1984, and characterized for sensory responses by Travers et al. in 1995 (Miller and Smith 1984, Travers and Norgren 1995). Here we used immunohistochemistry and RT-PCR to characterize this gingival chemosensory structure, consisting of taste buds and a minor salivary gland. Similar to the CV and foliate papillae, this novel retromolar chemosensory structure contains taste buds surrounding the orifice of ducts originating from a salivary gland (morphologically similar to the Von Ebner\u27s glands). This salivary gland is located below the mucosa of the retromolar gap, extending posteriorly in the retromolar trigone. Above the gland and ducts, taste buds are positioned on the surface of the retromolar gingival epithelium, surrounding the duct orifices. We determined that these taste buds have chemosensory features expressing many canonical taste signaling elements, including taste receptors. The composition of the secretions from the retromolar gland is unknown. The retromolar taste buds are responsible for a small portion of sensory gustatory perception (Travers and Norgren 1995). Interestingly, patients have reported taste changes following procedures involving third molar extraction, possibly due to the disruption of the retromolar tissue (Shafer, Frank et al. 1999, Akal, Kucukyavuz et al. 2004, Klasser, Utsman et al. 2008, Ridaura-Ruiz, Figueiredo et al. 2012). The retromolar taste structure possibly plays a role in taste perception and represents a potential novel pharmacological target for taste or dry mouth disorders

Complete genome amplification of Equine influenza virus subtype 2

This work reports a method for rapid amplification of the complete genome of equine influenza virus subtype 2 (H3N8). A ThermoScriptTM reverse transcriptase instead of the avian myeloblastosis virus reverse transcriptase or Moloney murine leukemia virus reverse transcriptase was used. This enzyme has demonstrated higher thermal stability and is described as suitable to make long cDNA with a complex secondary structure. The product obtained by this method can be cloned, used in later sequencing reactions or nested-PCR with the purpose of achieving a rapid diagnosis and characterization of the equine influenza virus type A. This detection assay might be a valuable tool for diagnosis and screening of field samples as well as for conducting molecular studies.En este trabajo comunicamos un método rápido que permite la amplificación del genoma completo del subtipo 2 (H3N8) del virus de la influenza equina. Se utilizó la enzima transcriptasa reversa ThermoScriptTM en lugar de la transcriptasa reversa del virus de la mieloblastosis aviar o la transcriptasa reversa del virus de la leucemia murina de Moloney. Esta enzima ha demostrado tener una alta estabilidad térmica y la capacidad de hacer largas copias de ADN con una estructura secundaria compleja. El producto obtenido por esta técnica puede ser clonado y utilizado posteriormente en reacciones de secuenciación o de PCR anidada con la finalidad de lograr un diagnóstico rápido y la caracterización del virus de la influenza equina tipo A. Este ensayo de detección puede llegar a ser una valiosa herramienta para el diagnóstico y el análisis de muestras de campo, así como para la realización de estudios moleculares

Primera comunciación del virus israelí de la parálisis aguda en colmenas asintomáticas de la República Argentina

Honey bee mortality has recently been associated with Israeli acute paralysis virus (IAPV), a proposed etiological agent for a new syndrome known as Colony Collapse Disorder. Bees infected with this virus show shivering wings, progress into paralysis, and finally die outside the hive. During the last years, honey bee mortality became a serious problem for Argentinean beekeepers. We herein report the preliminary results of a survey carried out to detect IAPV in samples taken from several Argentine provinces, by using a reverse transcription Polymerase Chain Reaction assay. Our data indicate the existence of high frequency of IAPV in asymptomatic hives of Argentina.Recientemente la mortalidad de las abejas melíferas ha sido asociada al virus israelí de la parálisis aguda (IAPV), propuesto como agente etiológico del denominado síndrome de despoblamiento de las colmenas. Las abejas infectadas con este virus presentan temblores en las alas que progresan hasta convertirse en parálisis, y finalmente mueren fuera de la colmena. Durante los últimos años, la mortalidad de las abejas melíferas se ha transformado en un serio problema para los productores de miel de la Argentina. Nosotros informamos aquí los resultados preliminares de un estudio realizado para detectar IAPV en muestras de colmenas provenientes de varias provincias argentinas utilizando la técnica de transcripción reversa-reacción en cadena de la polimerasa. Nuestros datos indican la presencia de IAPV en un alto porcentaje de las colonias estudiadas.Fil: Reynaldi, Francisco José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Departamento de Ciencias Biológicas. Centro de Investigaciones de Fitopatología. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones de Fitopatología; ArgentinaFil: Sguazza, Guillermo Hernán. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; ArgentinaFil: Tizzano, Marco Antonio. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Fuentealba, Nadia Analia. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Galosi, Cecilia Monica. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; ArgentinaFil: Pecoraro, Marcelo Ricardo. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Rinosporidiosis en equinos de Buenos Aires, Argentina

La rinosporidiosis es una enfermedad causada por Rhinosporidium seeberi, un organismo parasitario clasificado en la familia Rhinosporideacea, clase Micomycetozoa. Es una enfermedad endémica de la India, pero se notificaron algunos casos en Europa, África, América del Norte y América del Sur. El objetivo del presente estudio fue describir tres casos de rinosporidiosis en caballos de vida libre en diferentes ciudades de la provincia de Buenos Ares, Argentina. Confirmamos la presencia de R. seeberi en las muestras analizadas utilizando técnicas histopatológicas, PCR y secuenciación.Rhinosporidiosis is caused by Rhinosporidium seeberi, a parasitic organism of the family Rhinosporideacea family, class Micomycetozoa. The disease is endemic in India; however, some cases were reported in Europe, Africa, North America, and South America. The aim of the present study is to report three cases of rhinosporidiosis in wild horses in different cities of Buenos Aires province, Argentina. We confirm the presence of R. seeberi in the analyzed samples using histopathological and PCR sequencing techniques.Fil: Tizzano, Marco Antonio. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Della Vedova, Romina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Lopez, Ramon Andres. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Amor, Veronica Andrea. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Zubia, Candelaria. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Córdoba, Susana Beatríz. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr. C. G. Malbrán"; ArgentinaFil: Reynaldi, Francisco José. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

The cloning of the virus envelope glycoprotein F of canine distemper virus expressed in Pichia pastoris

Canine distemper virus (CDV) is a pathogen which affects members of the Canidae family, causing an acute, often fatal, systemic disease. CDV is an RNA virus of the family Paramyxoviridae that contains two envelope glycoproteins: F and HA. In this study, we focused on the envelope glycoprotein F as the main target for neutralizing antibodies produced after infection or vaccination. The complete coding region of the protein (60 kDa) was expressed in the methylotrophic yeast Pichia pastoris, obtained in a recombinant form and secreted to the culture medium. Later, to analyze its immunogenicity, the protein was combined with an oily adjuvant and used to inoculate mice. The results provide evidence supporting a potential application of this recombinant protein as a subunit vaccine.Facultad de Ciencias Veterinaria

Amplificación del genoma completo del subtipo 2 del virus de la influenza equina

This work reports a method for rapid amplification of the complete genome of equine influenza virus subtype 2 (H3N8). A ThermoScriptTM reverse transcriptase instead of the avian myeloblastosis virus reverse transcriptase or Moloney murine leukemia virus reverse transcriptase was used. This enzyme has demonstrated higher thermal stability and is described as suitable to make long cDNA with a complex secondary structure. The product obtained by this method can be cloned, used in later sequencing reactions or nested-PCR with the purpose of achieving a rapid diagnosis and characterization of the equine influenza virus type A. This detection assay might be a valuable tool for diagnosis and screening of field samples as well as for conducting molecular studies.En este trabajo comunicamos un método rápido que permite la amplificación del genoma completo del subtipo 2 (H3N8) del virus de la influenza equina. Se utilizó la enzima transcriptasa reversa ThermoScriptTM en lugar de la transcriptasa reversa del virus de la mieloblastosis aviar o la transcriptasa reversa del virus de la leucemia murina de Moloney. Esta enzima ha demostrado tener una alta estabilidad térmica y la capacidad de hacer largas copias de ADN con una estructura secundaria compleja. El producto obtenido por esta técnica puede ser clonado y utilizado posteriormente en reacciones de secuenciación o de PCR anidada con la finalidad de lograr un diagnóstico rápido y la caracterización del virus de la influenza equina tipo A. Este ensayo de detección puede llegar a ser una valiosa herramienta para el diagnóstico y el análisis de muestras de campo, así como para la realización de estudios moleculares.Facultad de Ciencias Veterinaria

First report of viral infections that affect Argentine honeybees

Honey is one of the most important agricultural products for export in Argentina. In fact, more than 3.5 million beehives and 50 000 beekeepers are related with this production, mainly located in Buenos Aires province. Honeybee mortality is a serious problem that beekeepers in Argentina have had to face during the last 3 years. It is known that the consequence of the complex interactions between environmental and beekeeping parameters added to the effect of different disease agents such as viruses, bacteria, fungi and parasitic mites may result in a sudden collapse of the colony. In addition, multiple viral infections are frequently detected concomitantly in bee colonies. We describe here the preliminary results of a survey of three honeybee-pathogenic viruses, acute bee paralysis viruses (ABPV), chronic bee paralysis viruses (CBPV) and Sacbrood viruses (SBV) detected during a screening of 61 apiaries located in the main honey producer province using a RT-PCR assay. This is the first molecular report of the presence of these viruses in Argentine apiaries.Facultad de Ciencias VeterinariasCentro de Investigaciones en FitopatologíaComisión de Investigaciones Científicas de la provincia de Buenos Aire