Publications by authors named "Marmol J"

Article Synopsis
  • - The study focuses on how mosquitoes and other insects detect odors using specialized ion channel complexes made up of an odorant-binding subunit (OR) and a co-receptor subunit (Orco).
  • - Researchers used cryo-electron microscopy to determine the structures of two different mosquito odorant receptor complexes, finding an unexpected ratio of one OR to three Orco subunits.
  • - The findings show that when an odorant binds to the OR subunit, it is enough to open the channel pore, offering insights into how these receptors evolved and how insects sense odors.
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Background: Insulin resistance is a critical cause of metabolic dysfunctions. Metabolic dysfunction is common in patients with cancer and is associated with higher cancer recurrence rates and reduced overall survival. Yet, insulin resistance is rarely considered in the clinic and thus it is uncertain how frequently this condition occurs in patients with cancer.

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Mosquitoes rely on their sense of smell to find humans to secure a blood meal, transmitting deadly diseases with their bite. In this issue of Cell, De Obaldía and colleagues examine why mosquitoes bite some people more than others and report an association with the level of carboxylic acids in the human skin odor.

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Olfactory systems must detect and discriminate amongst an enormous variety of odorants. To contend with this challenge, diverse species have converged on a common strategy in which odorant identity is encoded through the combinatorial activation of large families of olfactory receptors, thus allowing a finite number of receptors to detect a vast chemical world. Here we offer structural and mechanistic insight into how an individual olfactory receptor can flexibly recognize diverse odorants.

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An amendment to this paper has been published and can be accessed via a link at the top of the paper.

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Connections between the gut and brain monitor the intestinal tissue and its microbial and dietary content, regulating both physiological intestinal functions such as nutrient absorption and motility, and brain-wired feeding behaviour. It is therefore plausible that circuits exist to detect gut microorganisms and relay this information to areas of the central nervous system that, in turn, regulate gut physiology. Here we characterize the influence of the microbiota on enteric-associated neurons by combining gnotobiotic mouse models with transcriptomics, circuit-tracing methods and functional manipulations.

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Piezo1 is a mechanosensitive (MS) ion channel with characteristic fast-inactivation kinetics. We found a slowly-inactivating MS current in mouse embryonic stem (mES) cells and characterized it throughout their differentiation into motor-neurons to investigate its components. MS currents were large and slowly-inactivating in the stem-cell stage, and became smaller and faster-inactivating throughout the differentiation.

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The olfactory system must recognize and discriminate amongst an enormous variety of chemicals in the environment. To contend with such diversity, insects have evolved a family of odorant-gated ion channels comprised of a highly conserved co-receptor (Orco) and a divergent odorant receptor (OR) that confers chemical specificity. Here, we present the single-particle cryo-electron microscopy structure of an Orco homomer from the parasitic fig wasp Apocrypta bakeri at 3.

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Mechanical force sensation is fundamental to a wide breadth of biology from the classic senses of touch, pain, hearing, and balance to less conspicuous sensations of proprioception, blood pressure, and osmolarity and basic aspects of cell growth, differentiation, and development. These diverse and essential systems use force-gated (or mechanosensitive) ion channels that convert mechanical stimuli into cellular electrical signals. TRAAK, TREK1, and TREK2 are K-selective ion channels of the two-pore domain K (K2P) family that are mechanosensitive: they are gated open by increasing membrane tension.

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Living cells respond to mechanical forces applied to their outer membrane through processes referred to as "mechanosensation". Faced with hypotonic shock, to circumvent cell lysis, bacteria open large solute-passing channels to reduce the osmotic pressure gradient. In the vascular beds of vertebrate animals blood flow is regulated directly through mechanical distention-induced opening of stretch-activated channels in smooth muscle cells.

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TRAAK channels, members of the two-pore domain K(+) (potassium ion) channel family K2P, are expressed almost exclusively in the nervous system and control the resting membrane potential. Their gating is sensitive to polyunsaturated fatty acids, mechanical deformation of the membrane, and temperature changes. Physiologically, these channels appear to control the noxious input threshold for temperature and pressure sensitivity in dorsal root ganglia neurons.

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We describe the synthesis and characterization of a ruthenium-bipyridyl complex bearing a rhodamine-based fluorescent ligand. The complex is weakly fluorescent due to the quenching of rhodamine. Upon irradiation of the MLCT band it releases rhodamine in a fast and clean heterolytic reaction, increasing its fluorescence nearly 6-fold and making it the first visible-light activatable fluorophore based in transition metal chemistry.

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Since the introduction of the Prospective Payment System based on Diagnosis Related Groups (DRGs) in the U.S.A.

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