Biology subjects

Perlas, E.

Publications and source records attributed to Perlas, E..

7 recordsLinked to original sources

bioRxiv2025

The transcription of a single olfactory receptor per neuron is enforced by epigenetic silencing of their enhancers

The ability to discriminate thousands of odors in our environment requires each olfactory neuron to express a single olfactory receptor from hundreds of available genes. The biochemical mechanism enforcing this monogenic expression remains unknown. We show that deletion of the chromatin protein TRIM66 causes individual olfactory neurons to express multiple receptors at a high level, demonstrating that monogenic expression relies on an epigenetic silencing mechanism. Moreover, TRIM66 is specifically recruited to olfactory receptor gene super-enhancers during neuronal progenitor maturation, thereby silencing nearby olfactory receptor genes. Loss of monogenic expression disrupted axonal projections to the olfactory bulb, resulting in an aberrant topographic map and impaired social odor discrimination and reproductive behaviors. These findings uncover the chromatin-based silencing of super-enhancers as the mechanism underlying the organization of the mammalian olfactory system.

molecular biology↗

bioRxiv2022

Striated muscle-specific base editing enables correction of mutations causing dilated cardiomyopathy

Dilated cardiomyopathy (DCM) is the second most common cause for heart failure with no cure except a high-risk heart transplantation. Approximately 30% of DCM patients harbor heritable mutations which are amenable to CRISPR-based gene therapy1. However, challenges related to delivery of the editing complex and off-target concerns hamper the broad applicability of CRISPR agents in the heart2. We employed a combination of the viral gene transfer vector AAVMYO with superior targeting specificity of heart muscle tissue3 and CRISPR base editors to repair patient mutations in the cardiac splice factor Rbm20, which cause aggressive and arrhythmogenic DCM4. Using optimized conditions, we could improve splice defects in human iPSC-derived cardiomyocytes (iPSC-CMs) and repair >70% of cardiomyocytes in two Rbm20 knock-in mouse models that we generated to serve as an in vivo platform of our editing strategy. Treatment of juvenile mice restored the localization defect of RBM20 in 75% of cells and splicing of RBM20 targets including TTN. Three months after injection, cardiac dilation and ejection fraction reached wildtype levels. Single-nuclei RNA sequencing (snRNA-seq) uncovered restoration of the transcriptional profile across all major cardiac cell types and whole-genome sequencing (WGS) revealed no evidence for aberrant off-target editing. Our study highlights the potential of base editors combined with AAVMYO to achieve gene repair for treatment of hereditary cardiac diseases.

genetics↗

bioRxiv2022

The long noncoding RNA Charme supervises cardiomyocytes maturation by controlling cell differentiation programs in the developing heart

Long noncoding RNAs (lncRNAs) are emerging as critical regulators of heart physiology and disease, although the studies unveiling their modes-of-action are still limited to few examples. We recently identified pCharme, a chromatin-associated lncRNA whose functional knockout in mice results in defective myogenesis and morphological remodelling of the cardiac muscle. Here, we combined Cap-Analysis of Gene Expression (CAGE), single-cell (sc)RNA sequencing and whole-mount in situ hybridization analyses to study pCharme cardiac expression. Since the early steps of cardiomyogenesis, we found the lncRNA being specifically restricted to cardiomyocytes, where it assists the formation of specific nuclear condensates containing MATR3, as well as important RNAs for cardiac development. In line with the functional significance of these activities, pCharme ablation in mice results in a delayed maturation of cardiomyocytes, which ultimately leads to morphological alterations of the myocardium and ventricular hypo-trabeculation. Since congenital anomalies in myocardium are clinically relevant in humans and predispose patients to major complications, the identification of novel genes controlling cardiac morphology becomes crucial. Our study offers unique insights into a novel lncRNA-mediated regulatory mechanism promoting cardiomyocyte maturation and bears relevance to Charme locus for future theranostic applications.

molecular biology↗

bioRxiv2021

Induction of flight via midbrain projections to thecuneiform nucleus

The dorsal periaqueductal gray is a midbrain structure implicated in the control of defensive behaviors and the processing of painful stimuli. Electrical stimulation or optogenetic activation of excitatory neurons in dorsal periaqueductal gray results in freezing or flight behavior at low or high intensity, respectively. However, the output structures that mediate these defensive behaviors remain unconfirmed. Here we carried out a targeted classification of neuron types in dorsal periaqueductal gray using multiplex in situ sequencing and then applied cell-type and projection-specific optogenetic stimulation to identify projections from dorsal periaqueductal grey to the cuneiform nucleus that promoted goal-directed flight behavior. These data confirmed that descending outputs from dorsal periaqueductal gray serve as a trigger for directed escape behavior.

neuroscience↗

bioRxiv2019

NGF-mediated photoablation of nociceptors reduces pain behavior in mice

Nerve growth factor (NGF) and its receptors TrkA and p75 play a key role in the development and function of peripheral nociceptive neurons. Here we describe novel technology to selectively photoablate TrkA positive nociceptors through delivery of a phototoxic agent coupled to an engineered NGF ligand and subsequent near infrared (NIR) illumination. We demonstrate that this approach allows for on demand and localized reversal of pain behaviors in mouse models of acute, inflammatory, neuropathic and joint pain. To target peripheral nociceptors we generated a SNAP-tagged NGF derivative, NGFR121W that binds to TrkA/p75 receptors but does not provoke signaling in TrkA positive cells or elicit pain behaviors in mice. NGFR121W-SNAP was coupled to the photosensitizer IRDye(R)700DX phthalocyanine (IR700) and injected subcutaneously. Following NIR illumination of the injected area, behavioral responses to nociceptive mechanical and sustained thermal stimuli, but not innocuous stimuli, were substantially reduced. Similarly, in models of inflammatory, osteoarthritic and neuropathic pain, mechanical hypersensitivity was abolished for three weeks following a single treatment regime. We demonstrate that this loss of pain behavior coincides with the retraction of neurons from the skin which then re-innervate the epidermis after 3 weeks corresponding with the return of mechanical hypersensitivity. Thus NGFR121W-SNAP-mediated photoablation is a minimally invasive approach to reversibly silence nociceptor input from the periphery, and control pain and hypersensitivity to mechanical stimuli.

neuroscience↗

bioRxiv2017

Control of mechanical pain hypersensitivity through ligand-targeted photoablation of TrkB positive sensory neurons

SummaryMechanical allodynia is a major symptom of neuropathic pain whereby innocuous touch evokes severe pain. Here we identify a population of peripheral sensory neurons expressing TrkB that are both necessary and sufficient for producing pain from light touch after nerve injury. Mice in which TrkB-Cre expressing neurons are ablated are less sensitive to the lightest touch under basal conditions, and fail to develop mechanical allodynia in a model of neuropathic pain. Moreover, selective optogenetic activation of these neurons after nerve injury evokes marked nociceptive behavior. Using a phototherapeutic approach based upon BDNF, the ligand for TrkB, we perform molecule-guided laser ablation of these neurons and achieve long-term retraction of TrkB positive neurons from the skin and pronounced reversal of mechanical allodynia across multiple types of neuropathic pain. Thus we identify the peripheral neurons which transmit pain from light touch and uncover a novel pharmacological strategy for its treatment.\n\nHighlightsO_LITrkB+ neurons detect light touch under basal conditions\nC_LIO_LITrkB+ neurons convey mechanical allodynia in neuropathic pain states\nC_LIO_LIA photosensitizing derivative of BDNF allows for photoablation of TrkB+ neurons\nC_LIO_LIBDNF-guided photoablation reverses allodynia in multiple types of neuropathic pain\nC_LI

neuroscience↗

bioRxiv2017

Molecule guided laser ablation as a novel therapeutic strategy to control itch.

Itch is a major symptom of many chronic skin diseases that can exacerbate inflammation by provoking excessive scratching and causing skin damage. Here we develop a novel technology to control itch through molecular guided delivery of a phototoxic agent and near infrared (IR) illumination of the skin. Exploiting the selective binding of the pruritogen Interleukin-31 to itch sensing cells, we generate an engineered IL31SNAP ligand derivative (IL31K138A-SNAP) that binds to cells but does not evoke signaling or provoke scratching when injected in vivo. Conjugation of IL31K138A-SNAP to the photosensitizer IRDye(R)700DX phthalocyanine (IR700) and injection of the skin results in long-term reversal of scratching behavior evoked by IL31 upon near IR illumination. We further develop a topical preparation of IL31 K138A-SNAP-IR700 that strikingly, reverses behavioral and dermatological indicators in mouse models of Atopic Dermatitis (AD) and the genetic skin disease Familial Primary Localized Cutaneous Amyloidosis (FPLCA). We demonstrate that this therapeutic effect results from selective retraction of itch sensing neurons in the skin, breaking the cycle of itch and disruption of the skins barrier function. Thus, molecule guided photoablation is a powerful new technology for controlling itch and treating inflammatory skin diseases.

neuroscience↗