Biology subjects

Vazquez, N.

Publications and source records attributed to Vazquez, N..

6 recordsLinked to original sources

bioRxiv2026

Determinants of CCT motif specificity in WNK signaling and expansion of CCT like domains

WNK kinases regulate ion transport and cell volume through interactions with partner proteins such as SPAK, OSR1, NRBP and TSC22D proteins. These interactions are mediated by conserved C-terminal (CCT) domains that recognize short sequence motifs, but the rules governing this recognition remain incompletely defined. Here we show that these domains can be grouped into distinct structural classes with different binding preferences for motif variants. We identify a previously unrecognized motif that mediates binding to the second CCT domain of WNKs and show that interaction specificity is determined by conserved physicochemical features, including electrostatic contacts and aromatic interactions, rather than strict sequence conservation. We further identify a similar domain in the protein FERRY3 that can bind TSC22D motifs in isolation. These findings define a framework for interaction specificity in WNK signaling and suggest that this binding mechanism may extend beyond this pathway.

cell biology↗

bioRxiv2025

Targeting Pseudomonas aeruginosa Ventilator-associated pneumonia with a non-antibiotic and biolfilm-disrupting Live Biotherapeutic: Preclinical Safety and Efficacy study

Background.Ventilator-associated pneumonia (VAP) is the second most common hospital-acquired infection and is associated with high morbidity and mortality. The insertion of the endotracheal tube (ETT) compromises the hosts bronchial defenses and facilitates the formation of microbial biofilms and VAP. Although antibiotics remain the cornerstone treatment, their efficacy is often compromised by poor biofilm penetration and the prevalence of multidrug-resistant bacteria. This reveals the need to develop novel non-antibiotic therapeutic strategies. We engineered a non-pathogenic strain of the pulmonary bacteria Mycoplasma pneumoniae CV2 to express anti-biofilm and bactericidal enzymes (VAP platform). The therapeutic effect was validated in a murine model of Pseudomonas aeruginosa infection and ex vivo in ETTs of patients with P. aeruginosa-induced VAP. Methods.We evaluated the safety of an improved version of CV2 (CV8, Mycochassis) in a miniature pig model, and its efficacy with the VAP therapeutic platform (CV8_VAP) in a piglet model of P. aeruginosa-induced VAP. CV8_VAP was administered via intralobe instillation or nebulization. We assessed the platforms ability to degrade biofilms formed on ETTs in vivo and its impact on the airway microbiota. We evaluated bacterial load in the lungs, inflammatory responses, histopathological and the clinical outcomes to provide a comprehensive characterization of therapeutic efficacy and safety. Findings.VAP platform reduced biofilm thickness and P. aeruginosa load in ETTs and lungs, with the nebulized route showing enhanced efficacy. CV8_VAP contributed on microbiome diversity restoration. Inflammatory markers in the lung were markedly decreased, suggesting a local immunomodulatory effect. Interpretation.These findings support that CV8_VAP as a promising, non-antibiotic therapeutic strategy for treating VAP caused by P. aeruginosa. Funding.The project that gave rise to these results has received funding from "La Caixa" Foundation (HR18-00058), and the European Research Council under the European Unions Horizon 2020 research and innovation program (670216).

synthetic biology↗

bioRxiv2024

NRBP1 and TSC22D proteins impact distal convoluted tubule physiology through modulation of the WNK pathway

The With No lysine (WNK) kinases regulate processes such as cell volume and epithelial ion transport through the modulation of Cation Chloride Cotransporters such as the NaCl cotransporter, NCC, present in the distal convoluted tubule (DCT) of the kidney. Recently, the interaction of WNKs with Nuclear Receptor Binding Protein 1 (NRBP1) and Transforming Growth Factor {beta}-Stimulated Clone 22 Domain (TSC22D) proteins was reported. Here we explored the effect of NRBP1 and TSC22Ds on WNK signaling in vitro and in the DCT. TSC22D1.1, TSC22D2, and NRBP1 are localized in DCT WNK bodies, which are cytoplasmic biomolecular condensates associated with WNK activation. In HEK293 cells, long TSC22D isoforms and NRBP1 increase WNK4 activity. DCT-specific NRBP1 knockout mice have reduced NCC phosphorylation and activate a compensatory response. Thus, NRBP1 and long TSC22D proteins are positive modulators of WNK signaling and modulate Na+ reabsorption in the kidney. NRBP1 and TSC22Ds likely influence WNK signaling in other tissues, impacting various physiological processes. TeaserThe pseudokinase NRBP1 and its associated TSC22D proteins modulate WNK kinases to regulate sodium reabsorption in the kidney.

physiology↗

bioRxiv2024

The human ciliopathy protein RSG1 links the CPLANE complex to transition zone architecture

Cilia are essential organelles and variants in genes governing ciliary function result in ciliopathic diseases. The Ciliogenesis and PLANar polarity Effectors (CPLANE) protein complex is essential for ciliogenesis in animals models but remains poorly defined. Notably, all but one subunit of the CPLANE complex have been implicated in human ciliopathy. Here, we identify three families in which variants in the remaining CPLANE subunit CPLANE2/RSG1 also cause ciliopathy. These patients display cleft palate, tongue lobulations and polydactyly, phenotypes characteristic of Oral-Facial-Digital Syndrome. We further show that these alleles disrupt two vital steps of ciliogenesis, basal body docking and recruitment of intraflagellar transport proteins. Moreover, APMS reveals that Rsg1 binds the CPLANE and also the transition zone protein Fam92 in a GTP-dependent manner. Finally, we show that CPLANE is generally required for normal transition zone architecture. Our work demonstrates that CPLANE2/RSG1 is a causative gene for human ciliopathy and also sheds new light on the mechanisms of ciliary transition zone assembly.

cell biology↗

bioRxiv2023

miR-137 conferred robustness to the territorial restriction of the neural plate border

The neural plate border (NPB) of vertebrate embryos segregated from the neural plate (NP) and epidermal regions, and comprised an intermingled group of progenitors with multiple fate potential. Recent studies have shown that during the gastrula stage, TFAP2A acts as a pioneer factor in remodeling the epigenetic landscape required to activate components of the NPB induction program. Here we show that Tfap2a has two highly conserved binding sites for miR-137 and both display a reciprocal expression pattern at the NPB and NP respectively. In addition, ectopic miR-137 expression reduced TFAP2A, whereas its functional inhibition expanded their territorial distribution overlapping with PAX7. Furthermore, we demonstrated that loss of the de novo DNA methyltransferase DNMT3A expanded miR-137 expression to the NPB. Bisulfite sequencing showed a significantly higher level of non-canonical CpH methylation at the promoter of miR-137 when we compared NPB and NP samples. Our finding shows that miR-137 contributes to the robustness of NPB territorial restriction in vertebrate development.

developmental biology↗

bioRxiv2020

Protein turnover dynamics suggest a diffusion to capture mechanism for peri-basal body recruitment and retention of intraflagellar transport proteins

Intraflagellar transport (IFT) is essential for construction and maintenance of cilia. IFT proteins concentrate at the basal body, where they are thought to assemble into trains and bind cargoes for transport. To study the mechanisms of IFT recruitment to this peri-basal body pool, we quantified protein dynamics of eight IFT proteins, as well as five other basal body localizing proteins, using fluorescence recovery after photobleaching in vertebrate multiciliated cells. We found that members of the IFT-A and IFT-B protein complexes show distinct turnover kinetics from other basal body components. Additionally, known IFT sub-complexes displayed shared dynamics, and these dynamics were not altered during cilia regeneration as compared to homeostasis. Finally, we evaluated the mechanisms of basal body recruitment by depolymerizing cytosolic MTs, which suggested that IFT proteins are recruited to basal bodies through a diffusion-to-capture mechanism. Our survey of IFT protein dynamics provides new insights into IFT recruitment to basal bodies, a crucial step in ciliogenesis.

cell biology↗