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Biology subjects

Morales, P.

Publications and source records attributed to Morales, P..

8 recordsLinked to original sources

SYNBRIDGE: A VERSATILE FRAMEWORK FOR BIDIRECTIONAL INTERCONVERSION BETWEEN BIOBRICKS AND GOLDEN GATE ASSEMBLY STANDARDS

Component reusability and interoperability are fundamental to synthetic biology. While BioBricks laid the groundwork for part domestication, Golden Gate-based assembly standards, in particular Modular Cloning (MoClo), revolutionized multipart assembly. Despite widespread adoption, standardized conversion between these two popular frameworks remains challenging due to sequence incompatibilities. While de novo synthesis remains constrained by cost and sequence complexity, conventional PCR-based conversion suffers from off-target binding driven by sequence redundancy in multigene devices, unscalable primer optimization costs, and amplicon size constraints. To address interconversion from an engineering perspective, we present SynBridge: a closed-loop idempotent workflow for bidirectional BioBrick-MoClo conversion built around two core operations, Bri2Mo and Mo2Bri. As a proof of concept, we validated SynBridge by constructing a composite genetic system integrating a BioBrick module for LuxR-mediated RFP expression with a MoClo-assembled device for thermoregulated GFP expression. Quantitative cloning efficiency and functional characterization confirmed a robust and reproducible workflow that operates without requiring ad-hoc solutions. SynBridge provides a versatile engineering tool that ensures backward compatibility, maximizes part reusability, and establishes a standardized interchangeability framework suitable for automated procedures.

synthetic biology↗

Microtubule-associated protein 1S (MAP1S): a cardioprotective factor against post-myocardial infarction remodeling via apoptosis inhibition

Adverse cardiac remodeling following myocardial infarction (MI) are driven by processes including autophagy and apoptosis. While microtubule-associated protein 1S (MAP1S) is known to regulate autophagy, its role in the cardiac pathological conditions remains unclear. This study aimed to elucidate the role of MAP1S and its underlying mechanisms in pathological cardiac remodeling. Following MI, MAP1S knockout mice exhibited increased mortality, impaired cardiac function, and elevated apoptosis. Similarly, MAP1S silencing in cultured cardiomyocytes augmented apoptosis under oxidative stress. Mechanistic investigation revealed potential link to the Hippo pathway. MAP1S knockdown in cardiomyocytes increased Mammalian Ste-20 like 1/2 (MST1/2) activation and reduced Yes-associated protein (YAP) activity, potentially explaining apoptosis regulation. Conversely, MAP1S overexpression reduced apoptosis and positively modulated autophagy. Importantly, in vivo modRNA-mediated MAP1S overexpression protected against apoptosis and adverse remodeling. This study reveals that MAP1S protects the heart from excessive apoptosis and adverse remodeling following MI, likely by modulating the Hippo signaling pathway.

cell biology↗

Altered Use of Prior Expectations and Modified Neural Dynamics in a Mouse Model of Autism

In dynamic environments, updating beliefs based on past experiences (priors) is essential for optimal decision-making. Prior utilization is often impaired in psychiatric disorders, affecting perception and behavior. We investigate how Neurexin1 (Nrxn1 ) loss-of-function disrupts this process, providing insight into circuit deficits underlying sensorimotor dysfunction. While the synaptic role of Nrxn1 role is well studied, its impact on network dynamics and decision-making behavior remain unclear. Using widefield calcium imaging, we assess cortex-wide activity in mice performing a two-choice task to probe how priors influence visually-guided decisions. This task requires the mouse to combine sensory evidence with the prior probability over the stimulus side. We find Nrxn1 KO mice underutilized priors and were slower to update choices based on feedback. During decision-making, cortex-wide cortical activity is both elevated and increasingly correlated in Nrxn1 KO mice, independent of task period. Moreover, a larger fraction of cortical variance was explained by movement variables, consistent with stronger coupling of cortical activity to motor signals and a bias toward movement-related dynamics. These findings suggest that core computations underlying decision-making, such as integrating past experience with current evidence, depend on intact synaptic mechanisms shaped by genes like Nrxn1.

neuroscience↗

Toxoplasma effector TgWIP hijacks dendritic cell actin and motility via Nck1/Grb2 and the WAVE complex

The intracellular parasite Toxoplasma gondii enhances its dissemination to distant organs by hijacking infected leukocytes via a Trojan Horse mechanism. Upon infecting dendritic cells (DCs), Toxoplasma induces a hypermigratory phenotype characterized by podosome dissolution and formation of F-actin stress fibers. We previously showed that these cytoskeletal changes depend on the effector protein Toxoplasma WAVE complex-interacting protein (TgWIP) secreted from parasites to infected leukocytes. Here, we identify the host adaptor proteins Non-catalytic region of tyrosine kinase adaptor protein 1 and 2 (Nck1/2) and Growth factor receptor-bound protein 2 (Grb2) as direct TgWIP interactors. TgWIP mainly uses two distinct proline-rich regions (PRRs) to interact with Nck1 and Grb2. Mutating these PRRs abrogates TgWIP binding to Nck1 and Grb2 and diminishes podosome dissolution and DC hypermotility. Furthermore, we show that TgWIP directly interacts with the actin nucleation promoting factor WAVE Regulatory Complex (WRC) via a WRC-interacting receptor sequence (WIRS). Disrupting this interaction also influences actin cytoskeletal remodeling and DC hypermotility. Collectively, our data reveal that TgWIP directly interacts with multiple actin regulators, including Nck1, Grb2, and the WRC, to remodel the actin cytoskeleton of the host cells, elucidating a key mechanism that Toxoplasma exploits to enhance host cell migration and dissemination.

microbiology↗

Homodimerization of CB2 cannabinoid receptor triggered by a bivalent ligand enhances cellular signaling

G protein-coupled receptors (GPCRs) exist within a landscape of interconvertible conformational states and in dynamic equilibrium between monomers and higher-order oligomers, both influenced by ligand binding. Here, we have shown that a homobivalent ligand formed by equal chromenopyrazole moieties as pharmacophores, connected by 14 methylene units, can modulate the dynamics of the cannabinoid CB2 receptor (CB2R) homodimerization by simultaneously binding both protomers of the CB2R-CB2R homodimer. Computational and pharmacological experimentals showed that one of the ligand pharmacophores binds to the orthosteric site of one protomer, and the other pharmacophore to a membrane-oriented pocket between transmembranes 1 and 7 of the partner protomer. This provides unique pharmacological properties, such as increased potency in Gi binding and increased recruitment of {beta}-arrestin. Thus, by modulating dimerization dynamics, it may be possible to fine-tune CB2R activity with potentially improved therapeutic outcomes. HIGHLIGHTSO_LIA homobivalent ligand of CB2R (PM369) modulates the dynamics of receptor homodimerization C_LIO_LIPM369 binds to the orthosteric site of one protomer and to a complementary, membrane-facing, site of the other protomer C_LIO_LIPM369 triggers CB2R homodimerization via the TM 1/7 interface that provides unique pharmacological properties C_LIO_LIPM369 potentiates signaling, increased potency in Gi binding and increased recruitment of {beta}-arrestin C_LIO_LIThese results highlight new approaches to control GPCR signaling C_LI GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=122 SRC="FIGDIR/small/593612v1_ufig1.gif" ALT="Figure 1"> View larger version (37K): org.highwire.dtl.DTLVardef@1736aeborg.highwire.dtl.DTLVardef@707654org.highwire.dtl.DTLVardef@168925borg.highwire.dtl.DTLVardef@60bc11_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

Genetic diversity of the Atacama Desert shrub Huidobria chilensis in the context of geography and climate

Survival in hyperarid deserts is a major challenge for plant life, requiring the development of evolutionary strategies. The Atacama Desert presents harsh conditions such as limited rainfall, crusted soils, high soil salinity, high altitude, and intense solar radiation. These conditions, together with paleoclimatic variability since the past millions of years, have influenced the genetic structure and connectivity of plant populations, resulting in a diverse flora with high endemism. However, the diversification of most lineages appears to be relatively recent, in contrast to proposed age of the Atacama Desert and the onset, evolution and expansion of hyperarid conditions since the Late Oligocene and Early Miocene. A prominent exception is the Atacama paleoendemic Huidobria chilensis (Loasaceae), which is thought to be adapted to such conditions since the Eocene. Still, the environmental limits and thresholds for life in the Atacama remain poorly understood. To investigate the genetic structure in relation to the history of the Atacama Desert, we studied 186 individuals from 11 populations using genotyping-by-sequencing (GBS). Genome-wide single nucleotide polymorphisms (SNPs) were analyzed for population structure and genetic diversity. We identified three genetic clusters corresponding to geographic regions: the coastal region south of Tocopilla, the Coastal Cordillera around Chanaral, and the Copiapo watershed in the south. These clusters as well as genetic diversity were analyzed alongside rainfall, altitude, and landscape data. Although the genetic data generally supports isolation by distance as a major factor for genetic variation between populations, the study also reveals the influence of the topography on the distribution of H. chilensis and highlights the role of hydrologically connected watersheds and rivers in plant migration and colonization. This shapes the species evolutionary trajectory and genetic diversity. Understanding these patterns provides insights into the adaptation and survival strategies of plants in extreme desert environments such as the Atacama.

genetics↗

The CB1 receptor interacts with cereblon and drives cereblon deficiency-associated memory shortfalls

Cereblon/CRBN is a substrate-recognition component of the Cullin4A-DDB1-Roc1 E3 ubiquitin ligase complex. Destabilizing mutations in the human CRBN gene cause a form of autosomal recessive non-syndromic intellectual disability (ARNSID) that is modelled by knocking-out the mouse Crbn gene. A reduction in excitatory neurotransmission has been proposed as an underlying mechanism of the disease, but the intimate factors eliciting this impairment remain mostly unknown. Here we report that CRBN molecules selectively located on glutamatergic neurons are necessary for proper memory function. Combining various in vivo approaches, we show that the cannabinoid CB1 receptor (CB1R), a key suppressor of synaptic transmission, is overactivated in CRBN deficiency-linked ARNSID mouse models, and that the memory deficits observed in these animals can be rescued by acute CB1R-selective pharmacological antagonism. Molecular studies demonstrated that CRBN interacts physically with CB1R and impairs the CB1R-Gi/o-cAMP-PKA pathway in a ubiquitin ligase-independent manner. Taken together, these findings unveil that CB1R overactivation is a driving mechanism of CRBN deficiency-linked ARNSID and anticipate that the blockade of CB1R could constitute a new therapy for this orphan disease.

neuroscience↗

Predictive evolution of metabolic phenotypes using model-designed selection niches

Traits lacking fitness benefit cannot be directly selected for under Darwinian evolution. Thus, features such as metabolite secretion are currently inaccessible to adaptive laboratory evolution. Here, we utilize environment-dependency of trait correlations to enable Darwinian selection of fitness-neutral or costly traits. We use metabolic models to design selection niches and to identify surrogate traits that are genetically correlated with cell fitness in the selection niche but coupled to the desired trait in the target niche. Adaptive evolution in the selection niche and subsequent return to the target niche is thereby predicted to enhance the desired trait. We experimentally validate the theory by evolving Saccharomyces cerevisiae for increased secretion of aroma compounds in wine fermentation. Genomic, transcriptomic, and proteomic changes in the evolved strains confirmed the predicted flux re-routing to aroma biosynthesis. The use of model-designed selection niches facilitates the predictive evolution of fitness-costly traits for ecological and biotechnological applications.

systems biology↗