APYRASE1/2 mediate red light-induced de-etiolation growth in Arabidopsis seedlings.

In etiolated seedlings, red light (R) activates phytochrome and initiates signals that generate major changes at molecular and physiological levels. These changes include inhibition of hypocotyl growth and promotion of the growth of primary roots, apical hooks, and cotyledons. An earlier report showed that the sharp decrease in hypocotyl growth rapidly induced by R was accompanied by an equally rapid decrease in the transcript and protein levels of two closely related apyrases (APYs; nucleoside triphosphate-diphosphohydrolases) in Arabidopsis (Arabidopsis thaliana), APY1 and APY2, enzymes whose expression alters auxin transport and growth in seedlings. Here, we report that single knockouts of either APY inhibit R-induced promotion of the growth of primary roots, apical hooks, and cotyledons, and RNAi-induced suppression of APY1 expression in the background of apy2 inhibits R-induced apical hook opening. When R-irradiated primary roots and apical hook-cotyledons began to show a gradual increase in their growth relative to dark controls, they concurrently showed increased levels of APY protein, but in hook-cotyledon tissue, this occurred without parallel increases in their transcripts. In wild-type seedlings whose root growth is suppressed by the photosynthesis inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea, the R-induced increased APY expression in roots was also inhibited. In unirradiated plants, the constitutive expression of APY2 promoted both hook opening and changes in the transcript abundance of Small Auxin Upregulated RNA (SAUR), SAUR17 and SAUR50 that help mediate de-etiolation. These results provide evidence that the expression of APY1/APY2 is regulated by R and that APY1/APY2 participate in the signaling pathway by which phytochrome induces differential growth changes in different tissues of etiolated seedlings.

Advances in the MYB-bHLH-WD Repeat (MBW) Pigment Regulatory Model: Addition of a WRKY Factor and Co-option of an Anthocyanin MYB for Betalain Regulation.

Flavonoids are secondary metabolites derived from the general phenylpropanoid pathway and are widespread throughout the plant kingdom. The functions of flavonoids are diverse, including defense against phytopathogens, protection against UV light damage and oxidative stress, regulation of auxin transport and allelopathy. One of the most conspicuous functions of flavonoids has long attracted the attention of pollinators and scientist alike: the vivid shades of red, pink, orange, blue and purple on display in the flowers of angiosperms. Thus, flavonoid pigments have perhaps been the most intensely studied phenylpropanoids. From Mendel to McClintock and up to the present, studies centered on flavonoid pigments have resulted in some of the most important scientific discoveries of the last 150 years, including the first examples of transcriptional regulation in plants. Here we focus on the highly conserved MYB-bHLH-WD repeat (MBW) transcriptional complex model for the regulation of the flavonoid pigment pathway. We will survey the history of the MBW model spanning the last three decades, highlighting the major findings that have contributed to our current understanding. In particular, recent discoveries regarding WRKY protein control of the flavonoid pigment pathway and its relationship to the MBW complex will be emphasized. In addition, we will discuss recent findings about the regulation of the beet betalain pigment pathway, and how a MYB member of the MBW complex was co-opted to regulate this chemically unrelated but functionally equivalent pathway.

Genetic transformation technologies for the common dandelion, Taraxacum officinale.

BACKGROUND: Taraxacum officinale, or the common dandelion, is a widespread perennial species recognized worldwide as a common lawn and garden weed. Common dandelion is also cultivated for use in teas, as edible greens, and for use in traditional medicine. It produces latex and is closely related to the Russian dandelion, T. kok-saghyz, which is being developed as a rubber crop. Additionally, the vast majority of extant common dandelions reproduce asexually through apomictically derived seeds- an important goal for many major crops in modern agriculture. As such, there is increasing interest in the molecular control of important pathways as well as basic molecular biology and reproduction of common dandelion. RESULTS: Here we present an improved Agrobacterium-based genetic transformation and regeneration protocol, a protocol for generation and transformation of protoplasts using free DNA, and a protocol for leaf Agrobacterium infiltration for transient gene expression. These protocols use easily obtainable leaf explants from soil-grown plants and reagents common to most molecular plant laboratories. We show that common markers used in many plant transformation systems function as expected in common dandelion including fluorescent proteins, GUS, and anthocyanin regulation, as well as resistance to kanamycin, Basta, and hygromycin. CONCLUSION: Reproducible, stable and transient transformation methods are presented that will allow for needed molecular structure and function studies of genes and proteins in T. officinale.

Association of Hypertension with All-Cause Mortality among Hospitalized Patients with COVID-19.

It is unclear to which extent the higher mortality associated with hypertension in the coronavirus disease (COVID-19) is due to its increased prevalence among older patients or to specific mechanisms. Cross-sectional, observational, retrospective multicenter study, analyzing 12226 patients who required hospital admission in 150 Spanish centers included in the nationwide SEMI-COVID-19 Network. We compared the clinical characteristics of survivors versus non-survivors. The mean age of the study population was 67.5 ± 16.1 years, 42.6% were women. Overall, 2630 (21.5%) subjects died. The most common comorbidity was hypertension (50.9%) followed by diabetes (19.1%), and atrial fibrillation (11.2%). Multivariate analysis showed that after adjusting for gender (males, OR: 1.5, p = 0.0001), age tertiles (second and third tertiles, OR: 2.0 and 4.7, p = 0.0001), and Charlson Comorbidity Index scores (second and third tertiles, OR: 4.7 and 8.1, p = 0.0001), hypertension was significantly predictive of all-cause mortality when this comorbidity was treated with angiotensin-converting enzyme inhibitors (ACEIs) (OR: 1.6, p = 0.002) or other than renin-angiotensin-aldosterone blockers (OR: 1.3, p = 0.001) or angiotensin II receptor blockers (ARBs) (OR: 1.2, p = 0.035). The preexisting condition of hypertension had an independent prognostic value for all-cause mortality in patients with COVID-19 who required hospitalization. ARBs showed a lower risk of lethality in hypertensive patients than other antihypertensive drugs.

CLB19, a pentatricopeptide repeat protein required for editing of rpoA and clpP chloroplast transcripts.

RNA editing changes the sequence of many transcripts in plant organelles, but little is known about the molecular mechanisms determining the specificity of the process. In this study, we have characterized CLB19 (also known as PDE247), a gene that is required for editing of two distinct chloroplast transcripts, rpoA and clpP. Loss-of-function clb19 mutants present a yellow phenotype with impaired chloroplast development and early seedling lethality under greenhouse conditions. Transcript patterns are profoundly affected in the mutant plants, with a pattern entirely consistent with a defect in activity of the plastid-encoded RNA polymerase. CLB19 encodes a pentatricopeptide repeat protein similar to the editing specificity factors CRR4 and CRR21, but, unlike them, is implicated in editing of two target sites.

Borrelia hispanica como causa de fiebre recurrente / Borrelia hispanica as a cause of recurrent fever

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The role of annexin 1 in drought stress in Arabidopsis.

Annexins act as targets of calcium signals in eukaryotic cells, and recent results suggest that they play an important role in plant stress responses. We found that in Arabidopsis (Arabidopsis thaliana), AnnAt1 (for annexin 1) mRNA levels were up-regulated in leaves by most of the stress treatments applied. Plants overexpressing AnnAt1 protein were more drought tolerant and knockout plants were more drought sensitive than ecotype Columbia plants. We also observed that hydrogen peroxide accumulation in guard cells was reduced in overexpressing plants and increased in knockout plants both before and after treatment with abscisic acid. Oxidative protection resulting from AnnAt1 overexpression could be due to the low level of intrinsic peroxidase activity exhibited by this protein in vitro, previously linked to a conserved histidine residue found in a peroxidase-like motif. However, analyses of a mutant H40A AnnAt1 protein in a bacterial complementation test and in peroxidase activity assays indicate that this residue is not critical to the ability of AnnAt1 to confer oxidative protection. To further examine the mechanism(s) linking AnnAt1 expression to stress resistance, we analyzed the reactive S3 cluster to determine if it plays a role in AnnAt1 oligomerization and/or is the site for posttranslational modification. We found that the two cysteine residues in this cluster do not form intramolecular or intermolecular bonds but are highly susceptible to oxidation-driven S-glutathionylation, which decreases the Ca(2+) affinity of AnnAt1 in vitro. Moreover, S-glutathionylation of AnnAt1 occurs in planta after abscisic acid treatment, which suggests that this modification could be important in regulating the cellular function of AnnAt1 during stress responses.

La evaluación y diagnóstico del mobbing o acoso psicológico en la organización: el barómetro Cisneros / Assessing and diagnosing mobbing in organizations: the Cisneros barometer

El objetivo de este artículo es analizar la prevalencia del mobbing y de otras formas de violenciaen las organizaciones desde la metodología de evaluación y diagnóstico del mobbing utilizada en los estudios españoles Cisneros en los últimos años. Se analiza la prevalencia y las características del acoso psicológico en el trabajo a través del estudio más reciente detodos ellos: el estudio Cisneros VI. El estudio Cisneros VI es una encuesta sobre una muestra representativa de 4.250 trabajadores de todos los sectores de actividad de la comunidad de Madrid desarrollado en el marco de un convenio de investigación a iniciativa de la Consejeríade Empleo y Mujer de la Comunidad de Madrid. Los resultados del estudio confirman que los sectores con más casos de mobbing son las administraciones públicas, las empresas que proveen de servicios sociales y personales a la comunidad, el sector sanitario y, en general las actividades del sector terciario. La intensidad del acoso sigue el mismo patrón por sectores.Algunas diferencias aparecen en la tasa de prevalencia del mobbing dependiendo de la metodologíade evaluación del acoso según esta se haga con cargo a una definición de lo que es mobbing o con cargo a la existencia de conductas frecuentes de maltrato laboral. Se analiza el denominado problema del labelling y se propone una solución técnica de cara a la intervencióny a la prevención del acoso en la organización. En cuanto a la violencia física o verbal directa referida por los trabajadores contra ellos, se observa que el sector sanitario, los servicios subcontratados a empresas y el sector educativo figuran a la cabeza. En el mobbing se señalan diferencias según la posición del trabajador en la organización, resultando más frecuentemente acosados los administrativos, y los mandos intermedios. Operarios y especialistasaparecen como los grupos que refieren más acoso anterior en los últimos cinco años. El grupo profesional que presenta el acoso más antiguo es el de los mandos intermedios y el sector cuyos casos son más antiguos es la Administración pública. Casi uno de cada cuatro traba-jadores señala haber padecido mobbing anteriormente en su vida profesional. Casi uno de cada cuatro trabajadores señala existir mobbing en su unidad o departamento en la actualidad. Por modalidades se confirma la predominancia del mobbing descendente practicado por jefes sobre las demás modalidaddes, y se observa la existencia de un relevante porcentaje de casosde maltrato habitual procedente del exterior de la organización. Teniendo en cuenta el sexo de la víctima se observa que los acosadores varones acosan por igual a hombres y mujeres y que las mujeres y los gangs mixtos tienden a acosar más frecuentemente a las mujeres. Los trabajadores más mayores incrementan el riesgo de acoso. Se presentan las conductas de maltrato frecuente más señaladas y los daños asociados a ellas con correlaciones elevadas y significativas en todas las escalas clínicas que evalúa el estudio

This paper analyzes the prevalence of mobbing and other ways of violence among organizations by means of the methodology of assessment and diagnosis used in the Spanish “Cisneros” studies over the last 10 years –with particular reference to “Cisneros VI”. Led by theCisneros team, this study was developed in November 2005 thanks to an agreement with the Department of Employment and Women of the Madrid Autonomous Community. In thisstudy (the most extensive on mobbing ever in Spain) a survey was administered to a representative sample of 4,250 employees drawn from across industries in the Madrid Autonomous Community. In line with mobbing patterns shown in previous studies by this mobbingresearch agency, results showed that mobbing was by and large more prevalent among the employees of the service sectors –public administration, social services companies contracted by the Autonomous Community, media and communications and medical services.One out of four employees reported having witnessed mobbing cases in their department. One out of ten labelled themselves as victims of mobbing and over 20 percent reported more than one weekly mobbing behavior during the last 6 months. As for the mobbing patterns, 70percent of reported mobbing cases were of a hierarchical type, 16 percent were horizontal mobbing and 9 percent were inflicted on a superior by his/her subordinate. By sector, the prevalence is higher in the medical services followed by contracted services and the educationalsector. By position, employees, clerks and middle managers are more frequently mobbed. As for the gender, males harass victims regardless of their gender although the mixed gangs tend to inflict mobbing more frequently on women. The risk of mobbing seems also to be directlyrelated to the employee age. Depending on the method used to assess mobbing, different mobbing rates appear. Because of the problem for establishing a baseline for the self labelled victims in anti-mobbing protocols (in order to implement prevention programs) we used theCisneros Barometer. The most frequently reported mobbing behaviours are shown, along with damages significantly correlating in the clinical scales