TETRASPANIN 8-1 from Phaseolus vulgaris plays a key role during mutualistic interactions.

Arbuscular mycorrhizal (AM) fungi and rhizobia form two of the most important plant-microbe associations for the assimilation of phosphorus (P) and nitrogen (N). Symbiont-derived signals are able to coordinate the infection process by triggering multiple responses in the plant root, such as calcium influxes and oscillations, increased reactive oxygen species (ROS), cytoskeletal rearrangements and altered gene expression. An examination was made of the role of tetraspanins, which are transmembrane proteins that self-organize into tetraspanin web regions, where they recruit specific proteins into platforms required for signal transduction, membrane fusion, cell trafficking, and ROS generation. In plant cells, tetraspanins are scaffolding proteins associated with root radial patterning, biotic and abiotic stress responses, cell fate determination, plasmodesmata and hormonal regulation. Some plant tetraspanins, such as Arabidopsis thaliana TETRASPANIN 8 and TETRASPANIN 9 (AtTET8 and AtTET9) are associated with exosomes during inter-kingdom communication. In this study, a homolog of AtTET8, PvTET8-1, in common bean (Phaseolus vulgaris L. var. Negro Jamapa) was examined in roots during interactions with Rhizobium tropici and Rhizophagus irregularis. The promoter of PvTET8-1 contained several cis-acting regulatory DNA elements potentially related to mutualistic interactions, and PvTET8-1 was transcriptionally activated during AM fungal and rhizobial associations. Silencing it decreased the size and number of nodules, nitrogen fixation, and mycorrhizal arbuscule formation, whereas overexpressing it increased the size and number of nodules, and mycorrhizal arbuscule formation but decreased nitrogen fixation. PvTET8-1 appears to be an important element in both of these mutualistic interactions, perhaps through its interaction with NADPH oxidase and the generation of ROS during the infection processes.

Mental health impact by COVID-19 in hospitalized patients sample in Mexico City / Impacto en la salud mental en una muestra de pacientes hospitalizados por COVID-19 en la Ciudad de México

Una de las consecuencias de la pandemia es el aumento de la prevalencia de alteraciones mentales como la ansiedad, la depresión y el estrés. En este estudio transversal y observacional se evaluó la prevalencia de estrés, ansiedad y depresión en pacientes hospitalizados por COVID-19 así como la probable asociación con el impacto emocional recibido por familiares de pacientes hospitalizados por COVID-19. Cuarenta y cinco pacientes hospitalizados por COVID-19 con una edad promedio de 54.4 ± 9.6 años y cincuenta y cinco familiares de pacientes hospitalizados con una edad promedio de 43.2 ± 11.8 años respondieron una batería de preguntas y la encuesta DASS-21. Nuestros resultados revelaron una alta prevalencia de depresión, ansiedad y estrés identificados por DASS-21. En este estudio identificamos factores de riesgo asociados a la salud emocional como la edad (< 50 años: depresión RM = 2.99 [1.31, 6.80] p < .05 y ansiedad RM = 2.83 [1.15, 6.93], p < .05), el género (mujeres: ansiedad RM = 4.13 [1.57, 10.89], p < .05 y estrés RM = 5.38 [2.27, 12.8], p < .05) y el grupo de estudio (familiares: depresión RM = 3.83 [1.63, 8.96]; p < .05 , ansiedad RM = 3.60 [1.46, 8.88]; p < .05 y estrés RM = 3.30 [1.41, 7.70]; p < .05). Además, el género femenino y el nivel socioeconómico bajo de los pacientes (β = 3.23; 1.96) y familiares (β = 1.86; 2.31) se asociaron con puntuaciones más altas en ansiedad (p < .05) y estrés (p < .05). Concluimos que la muestra de pacientes con COVID-19 mantiene una alta prevalencia de alteraciones mentales y que algunos factores sociodemográficos se asocian con la magnitud de estos trastornos.(AU)

One of the consequences of pandemic is the increase in the prevalence of mental alterations such as anxiety, depression and stress. Since here, we aimed to determinate through a transversal and observa-tional studyprevalence of stress, anxiety and depression within hospital-ized patients by COVID-19 as well as their likely association with the emo-tional impact received by relatives with hospitalized patients by COVID-19. Forty-five COVID-19 hospitalized patients with mean age of 54.4 ± 9.6 yearsand fifty-five relatives with mean age of 43.2 ± 11.8 yearsan-swered a questions battery and DASS-21 survey. Our resultsrevealed high prevalence of depression, anxiety and stress assessed by DASS-21 sub-scales. We also identified risk factors associated with the emotional health such as age (<50 years: depression OR=2.99 [1.31, 6.80], p< .05 and anxiety OR=2.83 [1.15,6.93], p< .05), by gender (female: anxiety OR = 4.13 [1.57, 10.89], p< .05 and stress OR = 5.38 [2.27, 12.8], p< .05), by group of study (relatives: depression OR = 3.83 [1.63, 8.96]; p< .05, anxie-ty OR = 3.60 [1.46, 8.88]; p< .05 and stress OR = 3.30 [1.41, 7.70]; p< .05). Additionally, female gender and low socioeconomic status in patients (β= 3.23; 1.96) and relatives (β= 1.86; 2.31) were associated with higher scores in anxiety (p< .05) and stress (p <.05). We concluded that our sample of COVID-19 patients maintain a high prevalence of mental altera-tions and age, gender and socioeconomic status modify the magnitude of these disorders.(AU)

Differential tetraspanin genes expression and subcellular localization during mutualistic interactions in Phaseolus vulgaris.

Arbuscular mycorrhizal fungi and rhizobia association with plants are two of the most successful plant-microbe associations that allow the assimilation of P and N by plants, respectively. These mutualistic interactions require a molecular dialogue, i.e., legume roots exude flavonoids or strigolactones which induce the Nod factors or Myc factors synthesis and secretion from the rhizobia or fungi, respectively. These Nod or Myc factors trigger several responses in the plant root, including calcium oscillations, and reactive oxygen species (ROS). Furthermore, superoxide and H2O2 have emerged as key components that regulate the transitions from proliferation to differentiation in the plant meristems. Similar to the root meristem, the nodule meristem accumulates superoxide and H2O2. Tetraspanins are transmembrane proteins that organize into tetraspanin web regions, where they recruit specific proteins into platforms required for signal transduction, membrane fusion, cell trafficking and ROS generation. Plant tetraspanins are scaffolding proteins associated with root radial patterning, biotic and abiotic stress responses, cell fate determination, and hormonal regulation and recently have been reported as a specific marker of exosomes in animal and plant cells and key players at the site of plant fungal infection. In this study, we conducted transcriptional profiling of the tetraspanin family in common bean (Phaseolus vulgaris L. var. Negro Jamapa) to determine the specific expression patterns and subcellular localization of tetraspanins during nodulation or under mycorrhizal association. Our results demonstrate that the tetraspanins are transcriptionally modulated during the mycorrhizal association, but are also expressed in the infection thread and nodule meristem development. Subcellular localization indicates that tetraspanins have a key role in vesicular trafficking, cell division, and root hair polar growth.

Emerging roles of tetraspanins in plant inter-cellular and inter-kingdom communication.

Inter-cellular and inter-kingdom signaling systems of various levels of complexity regulate pathogenic and mutualistic interactions between bacteria, parasites, and fungi and animal and plant hosts. Inter-kingdom interactions between mutualistic bacteria such as rhizobia and legumes during nodulation and between fungi and plants during mycorrhizal associations, are characterized by the extensive exchange of molecular signals, which allow nitrogen and phosphate assimilation, respectively. A novel aspect of this signaling exchange is the existence of specific structures, the exosomes, that carry important molecules that shape the plant-pathogen interactions. Exosomes contain a wide array of molecules, such as lipids, proteins, messenger RNA, and microRNAs, that play important roles in cell-to-cell communication in animal and plant cells by affecting gene expression and other physiological activity in distant cells within the same organism (e.g., during cancer metastases and neuron injuries). In plant cells, it has been recently reported that exosomes go beyond organism boundaries and inhibit a pathogenic interaction in plants. Plant produce and send exosomes loaded with specific small miRNA which inhibit the pathogen infection, but the pathogen can also produce exosomes carrying pro-pathogenic proteins and microRNAs. Therefore, exosomes are the important bridge regulating the signal exchange. Exosomes are small membrane-bound vesicles derived from multivesicular bodies (MVBs), which carries selected cargos from the cytoplasm (protein, lipids, and microRNAs) and under certain circumstances, they fuse with the plasma membrane, releasing the small vesicles as cargo-carrying exosomes into the extracellular space during intercellular and inter-kingdom communication. Animal and plant proteomic studies have demonstrated that tetraspanin proteins are an integral part of exosome membranes, positioning tetraspanins as essential components for endosome organization, with key roles in membrane fusion, cell trafficking, and membrane recognition. We discuss the similarities and differences between animal tetraspanins and plant tetraspanins formed during plant-microbe interactions and their potential role in mutualistic communication.