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Rodriguez, I.

Publications and source records attributed to Rodriguez, I..

At least 19 recordsLinked to original sources

Nose-to-ground distance drives the evolution of mammalian odorant receptor repertoire size

The largest protein-coding gene family in mammals encodes the repertoire of chemosensors responsible for detecting odorants, namely odorant receptors (ORs). OR gene numbers vary widely across species, ranging from a few hundred in some primates to over two thousand in elephants. Here, we report that proximity to the ground, a rich source of olfactory cues, has broadly influenced the evolutionary expansion and contraction of OR mammalian repertoires. Analyzing 158 terrestrial mammalian species, we find a strong inverse correlation between nose-to-ground distance and the number of functional OR genes. In contrast, no significant association was found between nose-to-ground distance and the size of other chemoreceptor families, including vomeronasal and bitter-taste receptors. As a case study, we examined OR repertoire divergence between giraffe and okapi lineages, revealing that differential rates of gene duplication and pseudogenization resulted in giraffes possessing 25% fewer ORs than okapis. Together, our findings suggest that the chemical complexity of the olfactory environment has shaped the evolution of OR repertoires, providing new insights into gene family size and diversification in mammals.

evolutionary biology↗

Reproducible autosomal gene expression changes with loss of typical X and Y complement across tumor types

Although there are known sex differences in cancer incidence, severity, and treatment, the sex chromosomes are typically excluded from genomic analyses because of the unique technical challenges associated with assessing their copy number, sequence variation, and expression. Here we assess sex chromosome complement in three widely-used human genomics datasets from normal (non-cancerous) tissues, primary tumors, and cancer cell lines and study the effects on genome-wide gene expression. Expected sex chromosome complements based on reported patient sex were observed in non-cancerous tissues, but about half of tumors and cancer cell lines showed loss of typical sex chromosome gene expression across tissue types with three categories: loss of chromosome Y (LOY), loss of chromosome X (LOX) and reactivation of the inactive X chromosome (XaXa). Genes consistently differentially expressed in tumors with loss of chromosome X, loss of chromosome Y, or loss of X chromosome inactivation are associated with the hallmarks of cancer and include both sex-linked and autosomal genes from nearly all chromosomes, druggable genes, and genes with molecular functions relevant to cancer signaling, such as kinase activity. Strikingly, tumors that are X0, including tumors from female patients that have lost an X chromosome and tumors from male patients that have lost a Y chromosome, cluster together by gene expression profile. Patients with tumors that have LOX or LOY had poorer survival outcomes compared to those with tumors that had maintained their sex chromosome complement. Further, LOX and LOY eliminates nearly all of the differential gene expression between tumors from different patient sexes, affecting sex chromosomal and autosomal gene expression. Going forward, considering patient sex as well as the entire genome, including assessment of the sex chromosome complement, will provide additional insights into personalized tumor etiology, progression, treatment, and patient outcome. TeaserLoss of typical sex chromosome complement is present in primary tumors and cancer cell lines across tissue types. We identify consistent autosomal gene expression changes across multiple cancers when the sex chromosome complement is altered, and show that loss of sex chromosomes reduces tumor gene expression differences between patient sexes. We show that loss of sex chromosomes is also associated with poorer patient survival.

cancer biology↗

Protein aggregation capture assisted profiling of the thiol redox proteome

Oxidative damage is critical in various diseases, including cardiovascular and neurological conditions. Thiol redox reactions, acting as oxidative stress sensors, influence protein structure and function. Redox proteomics based on differential alkylation of reduced and oxidized Cys forms using mass spectrometry enables comprehensive analysis of thiol redox status in cells and tissues. We introduce PACREDOX, an innovative redox proteomics approach based on the Protein Aggregation Capture (PAC) protocol and we demonstrate its compatibility with library free data-independent acquisition (DIA). PACREDOX reduces preparation time and costs compared to traditional methods, such as FASILOX, while maintaining thiol and proteome coverage. To enable library-free DIA, we corrected in silico spectral libraries in DIA-NN using experimental retention time data from beta-methylthiol-modified peptides. PACREDOX with DIA quantified 4,000 protein groups and [~]45,000 modified peptides in myocardial tissue from a porcine model of atrial fibrillation, including over 8,000 cysteine-containing peptides, 30% of which were reversibly oxidized. Benchmarking PACREDOX and DIA against FASILOX in a myocardial infarction model reflects the potential and efficiency of this methodology to study oxidative damage. Overall, PACREDOX offers a high-throughput, cost-effective strategy for thiol redox proteome analysis, compatible with label-free quantitative workflows.

systems biology↗

A spatial single-cell atlas of the claustro-insular region uncovers key regulators of neuronal identity and excitability

The claustro-insular region is an evolutionarily conserved and extensively interconnected brain area, critical for functions such as attention, cognitive flexibility, interoception, and affective processing. Despite its importance, its cellular composition and organization remain poorly characterized, hindering a comprehensive understanding of the mechanisms underlying its diverse functions. By combining single-cell RNA sequencing and spatial transcriptomics, we created a high-resolution atlas of this region in mice, uncovering distinct neuronal subtypes and unexpected complexity. Leveraging this atlas, we investigated the role of NR4A2, a neuropsychiatric risk factor expressed in several claustro-insular neuronal subtypes. In an Nr4a2 haploinsufficiency model, we found that only claustrum neurons exhibited shifts in molecular identity. This identity shift, which involved the activation of a transcription factor cascade, was associated with alterations in neuronal firing activity. Our findings provide new insights into the cellular architecture of the claustro-insular region and highlights Nr4a2 as a master regulator of its components identities.

neuroscience↗

Analysis of the progression of cervical cancer in Guatemala- from pre-malignancy to invasive disease

To better understand cervical cancer progression, we analyzed RNA from 262 biopsies from women referred for colposcopy We determined HPV type and analyzed the expression of 51 genes. HPV31 was significantly more prevalent in precancer than stage 1 cancer and invasive cancer (p < 0.0001) and HPV16 increased in invasive disease (p < 0.0001). CCNE1, MELTF, and ULBP2 were significantly increased in HPV16-positive compared to HPV31 precancers while NECTIN2 and HLA-E expression decreased. Markers of the innate immune system, DNA repair genes, and cell cycle genes are significantly increased during cancer progression (p = 0.0001). In contrast, the TP53 and RB1 tumor suppressor gene expression is significantly decreased in cancer cells. TheT cell markers CD28 and FLT3LG expression decreased in cancer while FOXP3, IDO1, and ULBP2 expression increased. There is a significantly higher survival rate in individuals with increased expression of CD28 (p = 0.0005), FOXP3 (p = 0.0002), IDO1 (p = 0.038), FLT3LG (p = 0.026), APOBEC3B (p = 0.0011), and RUNX3 (p = 0.019), and a significantly lower survival rate in individuals with increased expression of ULBP2 (p = 0.035). These results will help us understand the molecular factors influencing the progression of cervical precancer to cancer.

cancer biology↗

The claustrum is critical for maintaining working memory information

Working memory (WM) enables the mammalian brain to temporarily store and manipulate information, supporting cognitive tasks and communication processes1,2. Rather than depending on a single specialized area, WM is thought to operate through a distributed network spanning cortical and subcortical regions3-5. A dedicated WM storage area would likely require broad reciprocal connections with various cortical regions to accommodate the diverse range of information WM retains. The claustrum (CLA), with its extensive bidirectional connections to the neocortex6-9, presents a compelling candidate for such a role. Here, we examined the involvement of the CLA in WM processes by recording CLA neuronal activity in mice engaged in olfactory and tactospatial delayed non-match-to-sample WM tasks. We identified cue- selective and delay-specific neurons in the CLA that maintained activity for tens of seconds after the stimulus presentation ended. Additionally, population activity in the CLA allowed for decoding of cue identity post-stimulus, although this signal gradually declined over time, aligning with animal behavior. Remarkably, both chemo- and optogenetic inhibition of CLA neurons severely impaired WM performance across multiple types of stored information, highlighting the CLAs critical role during both cue encoding, delay periods, and target comparison phases. These findings challenge the view that no single brain area is essential for WM storage and support a role for the CLA as an essential WM storage hub.

neuroscience↗

A toolbox for genetic targeting of the claustrum

The claustrum (CLA), a subcortical nucleus in mammals, essentially composed of excitatory projection neurons and known for its extensive connections with the neocortex, has recently been associated with a variety of functions ranging from consciousness to impulse control. However, research on the CLA has been challenging due to difficulties in specifically and comprehensively targeting its neuronal populations. In various cases, this limitation has led to inconsistent findings and a lack of reliable data. In the present work, we describe the expression profile of the Smim32 gene, which is almost exclusively transcribed in excitatory neurons of the CLA and the endopiriform nucleus, as well as in inhibitory neurons of the thalamic reticular nucleus. Leveraging this unique expression pattern, we developed a series of Cre- and Flippase-expressing knockin and BAC transgenic mouse lines with different expression profiles. With these novel tools in hand, we propose new standards for the interrogation of CLA function.

neuroscience↗

The claustrum drives large-scale interactions of cortical circuits relevant to long-term memory

The consolidation and recall of episodic memories rely on distributed cortical activity. The claustrum, a subcortical structure reciprocally connected to most of the cortex, may facilitate inter-areal communication necessary for these processes. We report here that the functional inhibition of claustral projection neurons affects directional interactions and the coordination of oscillatory neuronal patterns in the fronto-parietal network. Moreover, the inhibition of these neurons has a detrimental effect on concurrent oscillatory events relevant to the consolidation of contextual fear memory. Last, we demonstrate that biasing the directional flow of information between the latter two cortical areas enhances the retrieval of a remote contextual memory. We propose that the claustrum orchestrates inter-areal cortical interactions relevant to contextual memory processes by affecting the latency of neuronal responses. One-Sentence SummaryThe claustrum coordinates inter-areal cortical activity.

neuroscience↗

Metabolically Primed Multipotent Hematopoietic Progenitors Fuel Innate Immunity

Following infection, hematopoietic stem and progenitor cells (HSPCs) support immunity by increasing the rate of innate immune cell production but the metabolic cues that guide this process are unknown. To address this question, we developed MetaFate, a method to trace the metabolic expression state and developmental fate of single cells in vivo. Using MetaFate we identified a gene expression program of metabolic enzymes and transporters that confers differences in myeloid differentiation potential in a subset of HSPCs that express CD62L. Using single-cell metabolic profiling, we confirmed that CD62Lhigh myeloid-biased HSPCs have an increased dependency on oxidative phosphorylation and glucose metabolism. Importantly, metabolism actively regulates immune-cell production, with overexpression of the glucose-6-phosphate dehydrogenase enzyme of the pentose phosphate pathway skewing MPP output from B-lymphocytes towards the myeloid lineages, and expansion of CD62Lhigh HSPCs occurring to support emergency myelopoiesis. Collectively, our data reveal the metabolic cues that instruct innate immune cell development, highlighting a key role for the pentose phosphate pathway. More broadly, our results show that HSPC metabolism can be manipulated to alter the cellular composition of the immune system.

immunology↗

Transcriptional adaptation of sensory neurons to GPCR identity and activity

Sensory adaptation is critical to extract information from a changing world. Taking advantage of the extensive parallel coding lines present in the olfactory system, we explored the potential variations of neuronal identities before and after olfactory experience. We found that at rest, the transcriptomic profiles of olfactory sensory neuron populations are already highly divergent, specific to the olfactory receptor they express, and are surprisingly associated with the sequence of these latter. These divergent profiles further evolve in response to the environment, as odorant exposure leads to massive reprogramming via the modulation of transcription. Adenylyl cyclase 3, but not other main elements of the olfactory transduction cascade, plays a critical role in this activity-induced transcriptional adaptation. These findings highlight a broad range of sensory neuron identities that are present at rest and that adapt to the experience of the individual, thus providing a novel layer of complexity to sensory coding.

neuroscience↗

Whole genome sequences of Treponema pallidum subsp. endemicum isolated from Cuban patients: the non-clonal character of isolates suggests a persistent human infection rather than a single outbreak

Bejel (endemic syphilis) is a neglected non-venereal disease caused by Treponema pallidum subsp. endemicum (TEN). Although it is mostly present in hot, dry climates, a few cases have been found outside of these areas. The aim of this work was the sequencing and analysis of TEN isolates obtained from "syphilis patients" in Cuba, which is not considered an endemic area for bejel. Genomes were obtained by pool segment genome sequencing or direct sequencing methods, and the bioinformatics analysis was performed according to an established pipeline. We obtained four genomes with 100%, 81.7%, 52.6%, and 21.1% of broad coverage, respectively. The sequenced genomes revealed a non-clonal character, with nucleotide variability ranging between 0.2-10.3 nucleotide substitutions per 100 kbp among the TEN isolates. Nucleotide changes affected 27 genes, and the analysis of the completely sequenced genome also showed a recombination event between tprC and tprI, in TP0488 as well as in the intergenic region between TP0127-TP0129. Despite limitations in the quality of samples affecting broad sequencing coverage, the determined non-clonal character of the isolates suggests a persistent infection in the Cuban population rather than a single outbreak caused by imported case. Author summaryThe incidence of venereal syphilis has greatly increased in the last years, however endemic syphilis (bejel) which have been considered as a disease restricted to dry arid areas such as the Sahel and the Middle East, remain as a neglected disease. In Cuba, which is a tropical country, several bejel cases were unexpectedly detected few years ago in "syphilis" patients with no records of travel abroad or sex with foreign partners. In this study, we explored the whole genome sequences from four of the Cuban Treponema pallidum subsp. endemicum (TEN) isolates and the substantial genetic diversity detected among them suggests a persistent infection of TEN within the human population rather than a single outbreak of a TEN isolate introduced from an area where it is typically endemic. This finding has significant implications on this neglected and also possibly tropical disease in terms of geographical/temporal distribution, and highlights the importance of keeping in mind neglected diseases in apparently non-endemic areas.

microbiology↗

Plasmodium falciparum serology: A comparison of two protein production methods for analysis of antibody responses by protein microarray

The evaluation of protein antigens as putative serologic biomarkers of infection has increasingly shifted to high-throughput, multiplex approaches such as the protein microarray. In vitro transcription/translation (IVTT) systems - a similarly high-throughput protein expression method - are already widely utilised in the production of protein microarrays, though purified recombinant proteins derived from more traditional whole cell based expression systems also play an important role in biomarker characterisation. Here we have performed a side-by-side comparison of antigen-matched protein targets from an IVTT and purified recombinant system, on the same protein microarray. The magnitude and range of antibody responses to purified recombinants was found to be greater than that of IVTT proteins, and responses between targets from different expression systems did not clearly correlate. However, responses between amino acid sequence-matched targets from each expression system were more closely correlated. Despite the lack of a clearly defined relationship between antigen-matched targets produced in each expression system, our data indicate that protein microarrays produced using either method can be used confidently, in a context dependent manner, though care should be taken when comparing data derived from contrasting approaches. Statement of significance of the studyProtein microarray technology is increasingly being realised as a powerful tool in disease biomarker identification. Protein-based, serologic arrays are already well utilised in the characterisation of antibody responses to the malarial Plasmodium spp., drastically improving throughput and efficiency compared to more typical experimental assays. Such approaches have commonly made use of in vitro transcription/translation (IVTT) protein expression systems, though other protein expression methods are regularly employed. In this study we have directly compared antibody responses in a malaria endemic population, to matched protein antigens derived from both an IVTT and purified bacterial recombinant system in the same protein microarray. We demonstrated that the magnitude of measured antibody response to matched protein antigens tends to be greater to purified recombinants, rather than IVTT products. Further, our analysis showed highly variable levels of correlation of response between antigen-matched targets derived from each expression system, although relationships in antibody response were stronger between proteins with overlapping amino acid sequences. This study highlights the importance of considering the strengths and weaknesses of each expression system in the context of a protein microarray according to experimental hypotheses, and illustrates the need for attention when comparing data generated by these different methodologies.

immunology↗

HAP-multitag, a PET and positive MRI contrast nanotracer for the longitudinal characterization of vascular calcifications in atherosclerosis

Vascular microcalcifications are associated with atherosclerosis plaque instability and, therefore, to increased mortality. Because of this key role, several imaging probes have been developed for their in vivo identification. Among them [18F]FNa is the gold standard, showing a large uptake in the whole skeleton. Here, we push the field towards the combined anatomical and functional early characterization of atherosclerosis. For that, we have developed HAP-multitag, a bisphosphonate-functionalized 68Ga magnetic nanoparticle showing high affinity towards most common calcium salts present in microcalcifications, particularly hydroxyapatite. We characterized this interaction in vitro and in vivo, showing a massive uptake in the atherosclerotic lesion identified by PET and positive contrast MRI. In addition, this accumulation was found to be dependent on the calcification progression, with a maximum uptake in the microcalcification stage. These results confirmed the ability of HAP-multitag to identify vascular calcifications by PET/(T1)MRI during the vulnerable stages of the plaque progression.

bioengineering↗

The claustrum-medial prefrontal cortex network controls attentional set-shifting

In various mental disorders, dysfunction of the prefrontal cortex contributes to cognitive deficits. Here we studied how the claustrum (CLA), a nucleus sharing reciprocal connections with the cortex, may participate in these cognitive impairments. We show that specific ensembles of CLA and of medial prefrontal cortex (mPFC) neurons are activated during a task requiring cognitive control such as attentional set-shifting, i.e. the ability to shift attention towards newly relevant stimulus-reward associations while disengaging from irrelevant ones. CLA neurons exert a direct excitatory input on mPFC pyramidal cells, and chemogenetic inhibition of CLA neurons suppresses the formation of specific mPFC assemblies during attentional set-shifting. Furthermore, impairing the recruitment of specific CLA assemblies through opto/chemogenetic manipulations prevents attentional set-shifting. In conclusion, we propose that the CLA controls the reorganization of mPFC ensembles to enable attentional set-shifting, emphasizing a potential role of the CLA-mPFC network in attentional dysfunctions.

neuroscience↗

Impact of a rapid decline in malaria transmission on antimalarial IgG subclasses and avidity

Understanding how immunity to malaria is affected by declining transmission is important to aid vaccine design and understand disease resurgence. Both IgG subclasses and avidity of antigen-specific responses are important components of an effective immune response.Using a multiplex bead array assay, we measured the total IgG, IgG subclasses, and avidity profiles of responses to 18 P. falciparum blood stage antigens in samples from 160 Ugandans collected at 2 time points during high malaria transmission and 2 time points following a dramatic reduction in transmission.Results demonstrated that, for the antigens tested, (i) the rate of decay of total IgG following infection declined with age and was driven consistently by the decrease in IgG3 and occasionally the decrease in IgG1; (ii) the proportion of IgG3 relative to IgG1 in the absence of infection increased with age; (iii) the increase in avidity index (the strength of association between the antibody and antigen) following infection was largely due to a rapid loss of non-avid compared to avid total IgG; and (iv) both avid and non-avid total IgG in the absence of infection increased with age.Further studies are required to understand the functional differences between IgG1 and IgG3 in order to determine their contribution to the longevity of protective immunity to malaria. Measuring changes in antibody avidity may be a better approach of detecting affinity maturation compared to avidity index due to the differential expansion and contraction of high and low avidity total IgG.Competing Interest StatementThe authors have declared no competing interest.View Full Text

immunology↗

Competition NMR for Detection of Hit/Lead Inhibitors of Protein-Protein Interactions

Screening for small-molecule fragments that can lead to potent inhibitors of protein-protein interactions (PPIs) is often a laborious step as the fragments cannot dissociate the targeted PPI due to their low M-mM affinities. Here, we describe an NMR competition assay - called w-AIDA-NMR (weak-Antagonist Induced Dissociation Assay-NMR) - that is sensitive to weak M-mM ligand-protein interactions and which can be used in initial fragment screening campaigns. By introducing point mutations in the complexs protein that is not targeted by the inhibitor, we lower the effective affinity of the complex allowing for short fragments to dissociate the complex. We illustrate the method with the compounds that block the Mdm2/X-p53 and PD-1/PD-L1 oncogenic interactions. Targeting the PD-/PD-L1 PPI has profoundly advanced the treatment of different types of cancers.

biophysics↗

A 21-year survey of from bloodstream infections (BSIs) in a tertiary hospital reveals how community-hospital dynamics, influence local BSI rates, the trends of the B2 phylogroup and the STc131 pandemic clone

This is a longitudinal study comprising 649 Escherichia coli (EC) isolates representing all 7165 EC-BSI episodes recorded in a hospital (1996-2016). Strains analysis included clonal identification (phylogenetic groups/subgroups, STc131 subclades, PFGE, and WGS), antibiotic susceptibility (13 antibiotics), and virulence-associated genes (VAGs, 29 genes). The incidence of BSI-EC increased from 1996 to 2016 (5.5 to 10.8 BSI episodes/1000 hospitalizations, average 7-8/1000). B2 isolates predominate (53%), subgroups B2-I (STc131), B2-II, B2-IX, and B2-VI representing 25%, 25%, 14%, and 9%, respectively. Intertwined waves of community-acquired (CA) + healthcare-associated and community-onset healthcare-associated (HCA), and hospital-acquired (HA) episodes of both B2 and non-B2 phylogroups occurred. A remarkable increase was only observed for B2-I-STc131 (C1/C2 subclades), with oscillations for other B2 subgroups and phylogroups throughout the years. Epidemic and persistent clones (comprising isolates with highly similar/identical-PFGE types and genomes differing in 18-97 SNPs) of B2-I (STc131), B2-II (STc73), B2-III (STc127), B2-IX (STc95), and B2-VI (STc12) were recovered from different patients, most at hospital admission, for long periods (2-17 years), ESBL producers or resistance to ciprofloxacin in B2 isolates were almost restricted to B2-I (STc131) subclade C. STc131 contributed to increasing the B2 rates but only transiently altered the EC-population structure. The increase of EC-BSI was determined by waves of CA+HCA-BSI episodes that predate the waves of HA-BSI. Besides the risk of hospital transmission that led to temporal increases in BSIs, this study suggests that EC-populations/clones from community-based healthy individuals may occasionally have an epidemic structure and provide a source of transmissible strains influencing the HA-BSIs incidence. IMPORTANCESepsis is the third cause of mortality in Western countries and one of the Global Health threads recognized by the WHO since 2017. Despite Escherichia coli constitutes the most common cause of bloodstream infections (BSI), its epidemiology is not fully understood, in part due to the scarcity of local and longitudinal studies. Our work analyzes the long-term dynamics of E. coli causing bacteremia in a single institution and reveals waves of different clonal lineages that emerge periodically and successfully spread afterward in both the community and hospitals. Because the origin of BSI-E. coli infections is the gut, the microbiota of healthy individuals might occasionally have an epidemic structure, providing a source of E. coli strains to influence the incidence of hospital BSIs. The study complements previous fractionated observations focusing on specific E. coli lineages or antibiotic-resistant isolates in the last decades and helps to understand the epidemiology of E. coli BSIs and the dynamics of pandemic clones.

microbiology↗

SARS-CoV-2 receptor and entry genes are expressed by sustentacular cells in the human olfactory neuroepithelium

Various reports indicate an association between COVID-19 and anosmia, suggesting an infection of the olfactory sensory epithelium, and thus a possible direct virus access to the brain. To test this hypothesis, we generated RNA-seq libraries from human olfactory neuroepithelia, in which we found substantial expression of the genes coding for the virus receptor angiotensin-converting enzyme-2 (ACE2), and for the virus internalization enhancer TMPRSS2. We analyzed a human olfactory single-cell RNA-seq dataset and determined that sustentacular cells, which maintain the integrity of olfactory sensory neurons, express ACE2 and TMPRSS2. We then observed that the ACE2 protein was highly expressed in a subset of sustentacular cells in human and mouse olfactory tissues. Finally, we found ACE2 transcripts in specific brain cell types, both in mice and humans. Sustentacular cells thus represent a potential entry door for SARS-CoV-2 in a neuronal sensory system that is in direct connection with the brain.

neuroscience↗