Pepino mosaic virus RNA-Dependent RNA Polymerase POL Domain Is a Hypersensitive Response-Like Elicitor Shared by Necrotic and Mild Isolate

[SPA] El virus del mosaico del pepino dulce (PepMV) es un patógeno emergente que representa una grave amenaza para la producción de tomate. Las enfermedades inducidas por PepMV se manifiestan con una amplia gama de síntomas, incluyendo la necrosis sistémica. Nuestros resultados muestran que la acumulación de PepMV depende tanto del aislado del virus, como de la variedad de tomate o las condiciones ambientales, asociado todo ello al desarrollo de la necrosis. La sustitución de una lisina por un ácido glutámico en la posición 67 del triple bloque de genes (TGB3), previamente descrita como un determinante de la necrosis, parece favorecer una mayor acumulación del virus pero no parece ser el elemento elicitor de la necrosis sistémica. La sobreexpresión tanto de TGB3 como del dominio polimerasa (POL) de la replicasa (RdRp) produjo necrosis, aunque sólo la expresión local de POL desencadenó síntomas caracteristos de HR. En conjunto, nuestros datos sugieren que el dominio RdRp-POL desempeña un papel importante en la inducción de necrosis de PepMV, dependiendo del nivel de acumulación del virus, que puede ser modulado por la naturaleza de TGB3, el genotipo del huesped y las condiciones ambientales. [ENG] Pepino mosaic virus (PepMV) is an emerging pathogen that represents a serious threat to tomato production worldwide. PepMV-induced diseases manifest with a wide range of symptoms, including systemic necrosis. Our results showed that PepMV accumulation depends on the virus isolate, tomato cultivar, and environmental conditions, and associates with the development of necrosis. Substitution of lysine for glutamic acid at position 67 in the triple gene block 3 (TGB3) protein, previously described as a necrosis determinant, led to increased virus accumulation and was necessary but not sufficient to induce systemic necrosis. Overexpression of both TGB3 and the polymerase domain (POL) of the RNA-dependent RNA polymerase (RdRp) resulted in necrosis, although only local expression of POL triggered HR-like symptoms. Altogether, our data suggest that the RdRp-POL domain plays an important role in PepMV necrosis induction, with necrosis development depending on the virus accumulation level, which can be modulated by the nature of TGB3, host genotype and environmental conditions.Agradecer la financiación del Ministerio de Economía y Competitividad (AGL2012-37390 ) y la fundación Séneca por la financiación de la Beca FPI

Measurement of ϒ production in pp collisions at √s = 2.76 TeV

The production of ϒ(1S), ϒ(2S) and ϒ(3S) mesons decaying into the dimuon final state is studied with the LHCb detector using a data sample corresponding to an integrated luminosity of 3.3 pb−1 collected in proton–proton collisions at a centre-of-mass energy of √s = 2.76 TeV. The differential production cross-sections times dimuon branching fractions are measured as functions of the ϒ transverse momentum and rapidity, over the ranges pT < 15 GeV/c and 2.0 < y < 4.5. The total cross-sections in this kinematic region, assuming unpolarised production, are measured to be σ (pp → ϒ(1S)X) × B ϒ(1S)→μ+μ− = 1.111 ± 0.043 ± 0.044 nb, σ (pp → ϒ(2S)X) × B ϒ(2S)→μ+μ− = 0.264 ± 0.023 ± 0.011 nb, σ (pp → ϒ(3S)X) × B ϒ(3S)→μ+μ− = 0.159 ± 0.020 ± 0.007 nb, where the first uncertainty is statistical and the second systematic

Study of the doubly charmed tetraquark T+cc

Quantum chromodynamics, the theory of the strong force, describes interactions of coloured quarks and gluons and the formation of hadronic matter. Conventional hadronic matter consists of baryons and mesons made of three quarks and quark-antiquark pairs, respectively. Particles with an alternative quark content are known as exotic states. Here a study is reported of an exotic narrow state in the D0D0π+ mass spectrum just below the D*+D0 mass threshold produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The state is consistent with the ground isoscalar T+cc tetraquark with a quark content of ccu⎯⎯⎯d⎯⎯⎯ and spin-parity quantum numbers JP = 1+. Study of the DD mass spectra disfavours interpretation of the resonance as the isovector state. The decay structure via intermediate off-shell D*+ mesons is consistent with the observed D0π+ mass distribution. To analyse the mass of the resonance and its coupling to the D*D system, a dedicated model is developed under the assumption of an isoscalar axial-vector T+cc state decaying to the D*D channel. Using this model, resonance parameters including the pole position, scattering length, effective range and compositeness are determined to reveal important information about the nature of the T+cc state. In addition, an unexpected dependence of the production rate on track multiplicity is observed