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Garcia-Moreno, A.

Publications and source records attributed to Garcia-Moreno, A..

6 recordsLinked to original sources

Peripheral membrane proteins modulate stress tolerance by safeguarding cellulose synthases

Controlled primary cell wall remodeling adapts plant growth under stressful conditions, but how these changes are conveyed to adjust cellulose synthesis is unknown. Here, we identify the Tetratricopeptide Thioredoxin-Like (TTL) proteins as new members of the cellulose synthase complex (CSC) and describe their unique and hitherto unknown dynamic association with the CSC under cellulose-deficient conditions. We find that TTLs are essential for maintaining cellulose synthesis under salinity stress, establishing a stress-resilient cortical microtubule array, and stabilizing CSCs at the plasma membrane. To fulfill these functions, TTLs interact with Cellulose Synthase1 (CESA1) and engage with cortical microtubules to promote their polymerization. We propose that TTLs function as bridges connecting stress perception with dynamic regulation of cellulose biosynthesis at the plasma membrane. One Sentence SummaryTTLs are peripheral membrane proteins that maintain the integrity of the cellulose synthase complex upon adverse conditions.

plant biology↗

Wireless networks of injectable microelectronic stimulators based on rectification of volume conducted high frequency currents

ObjectiveTo develop and in vivo demonstrate threadlike wireless implantable neuromuscular microstimulators that are digitally addressable. ApproachThese devices perform, through its two electrodes, electronic rectification of innocuous high frequency current bursts delivered by volume conduction via epidermal textile electrodes. By avoiding the need of large components to obtain electrical energy, this approach allows the development of thin devices that can be intramuscularly implanted by minimally invasive procedures such as injection. For compliance with electrical safety standards, this approach requires a minimum distance, in the order of millimeters or a very few centimeters, between the implant electrodes. Additionally, the devices must cause minimal mechanical damage to tissues, avoid dislocation and be adequate for long-term implantation. Considering these requirements, the implants were conceived as tubular and flexible devices with two electrodes at opposite ends and, at the middle section, a hermetic metallic capsule housing the electronics. Main resultsThe developed implants have a submillimetric diameter (0.97 mm diameter, 35 mm length) and consist of a microcircuit, which contains a single custom-developed integrated circuit, housed within a titanium capsule (0.7 mm diameter, 6.5 mm length), and two platinum-iridium coils that form two electrodes (3 mm length) located at opposite ends of a silicone body. These neuromuscular stimulators are addressable, allowing to establish a network of microstimulators that can be controlled independently. Their operation was demonstrated by injecting a few of them in the hind limb of anesthetized rabbits and inducing controlled and independent contractions. SignificanceThese results show the feasibility of manufacturing threadlike wireless addressable neuromuscular stimulators by using fabrication techniques and materials well established for chronic electronic implants. This paves the way to the clinical development of advanced motor neuroprostheses formed by dense networks of such wireless devices.

bioengineering↗

GeneCodis 4: Expanding the modular enrichment analysis to regulatory elements

GeneCodis is a web-based tool for functional enrichment analysis that allows researchers to integrate different sources of annotations. It extracts sets of significant concurrent annotations and assigns a statistical score to evaluate those that are significantly enriched in the input list. Since its first release in 2007, it has been widely employed to analyze lists of genes in order to interpret the underlying biological mechanisms. Here we present GeneCodis 4, a new release that expands the functional analysis provided by the application, to accept regulatory elements, including lists of, transcription factors, CpG sites and miRNAs. It also incorporates new annotation databases and improved interactive visualizations functionalities to explore results. GeneCodis 4 is freely available at https://genecodis.genyo.es.

bioinformatics↗

Powering electronic implants by high frequency volume conduction: in human validation

Wireless power transfer (WPT) is frequently used as an alternative to batteries to accomplish miniaturization in electronic medical implants (eMIs). However, established WPT methods require bulky parts within the implant or cumbersome external systems, hindering minimally invasive deployments and the development of networks of eMIs. As an alternative, we propose a WPT approach based on volume conduction of high frequency (HF) current bursts. These currents are applied through external textile electrodes and are collected by the eMIs through two electrodes at their opposite ends. This approach avoids bulky components to obtain power, making it possible to develop implants with a flexible threadlike conformation. In here we study in humans if HF (6.78 MHz) current bursts complying with safety standards and applied through two textile electrodes strapped around a limb can provide substantial powers from pairs of implanted electrodes. Time averaged electric powers obtained from needle electrodes (diameter = 0.4 mm, length = 3 mm, separation = 30 mm) inserted into arms and lower legs of five healthy participants were 5.9 {+/-} 0.7 mW and 2.4 {+/-} 0.3 mW respectively. We also report a procedure to characterize the coupling between the external system and the implants using two-port impedance models generated from medical images. The results demonstrate for the first time in humans that innocuous and imperceptible HF current bursts that flow through the tissues by volume conduction can be used to wirelessly power threadlike eMIs, overcoming the limitations of existing WPT methods in terms of minimal invasiveness and usability.

bioengineering↗

A comprehensive and centralized database for exploring omics data in Autoimmune Diseases

Autoimmune diseases are heterogeneous pathologies with difficult diagnosis and few therapeutic options. In the last decade, several omics studies have provided significant insights into the molecular mechanisms of these diseases. Nevertheless, data from different cohorts and pathologies are stored independently in public repositories and a unified resource is imperative to assist researchers in this field. Here, we present ADEx (https://adex.genyo.es), a database that integrates 82 curated transcriptomics and methylation studies covering 5609 samples for some of the most common autoimmune diseases. The database provides, in an easy-to-use environment, advanced data analysis and statistical methods for exploring omics datasets, including meta-analysis, differential expression or pathway analysis.

bioinformatics↗

TTL proteins scaffold brassinosteroid signaling components at the plasma membrane to optimize signal transduction in plant cells

Brassinosteroids (BRs) form a group of steroidal hormones essential for plant growth, development and stress responses. Here, we report that plant-specific TETRATRICOPEPTIDE THIOREDOXIN-LIKE (TTL) proteins are positive regulators of BR signaling functioning as scaffold for BR signaling components in Arabidopsis. TTL3 forms a complex with all core components involved in BR signaling, including the receptor kinase BRASSINOSTEROID INSENSITIVE1 (BRI1), the transcription factor BRASSINAZOLE RESISTANT1 (BZR1) and the phosphatase BRI1-SUPPRESSOR1 (BSU1), but excluding the co-receptor BAK1. TTL3 is mainly localized in the cytoplasm, but BR treatment increases its localization at the plasma membrane, where it strengthens the association with BR signaling components. Consistent with a role in BR signaling, mutations in TTL3 and related TTL1 and TTL4 genes cause reduced BR responsiveness. We propose a mechanistic model for BR signaling, in which cytoplasmic/nuclear BR components bound to TTL proteins are recruited to the plasma membrane upon BR perception, which in turn allows the assembly of a BR signaling complex, leading to the de-phosphorylation and nuclear accumulation of the transcription factors BZR1 and BES1.

molecular biology↗