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Biology subjects

Lu, Y.-J.

Publications and source records attributed to Lu, Y.-J..

8 recordsLinked to original sources

Dissociable Oscillatory Alpha and Aperiodic Neural Dynamics Underlie Atypical Attentional Control in Children With Attention-Deficit/Hyperactivity Disorder (ADHD)

Children with attention-deficit/hyperactivity disorder (ADHD) often have difficulty maintaining goal-directed attention when task-relevant and task-irrelevant information compete for processing resources. The present study investigated whether this difficulty reflects distinct abnormalities in demand-related attentional regulation and distractor-related neural responses. We recorded electroencephalography (EEG) signals from 45 children with ADHD and 45 typically developing (TD) children while they performed a visual detection task under low and high visual demands, with simultaneous task-irrelevant standard and deviant sounds. EEG power spectra were parameterized to separate oscillatory alpha activity from aperiodic activity, as putative indices of attentional regulation and cortical excitation/inhibition (E/I) balance, respectively. TD children showed adaptive demand-related alpha modulation, whereas children with ADHD showed an atypical alpha response pattern, including reduced frontal modulation and atypical posterior alpha enhancement; this demand-related group difference was observed in oscillatory alpha activity but not in aperiodic activity. In contrast, ADHD-related abnormalities in responses to auditory distractors were more clearly reflected in the aperiodic slope. Children with ADHD showed atypical distractor-related aperiodic modulation, suggesting reduced stability of neural background activity, potentially reflecting disrupted cortical E/I balance when irrelevant sounds had to be ignored. Furthermore, multivariate machine learning classification demonstrated that relying on these sensitive neural signatures yielded robust discrimination between children with ADHD and TD controls, with significant predictive performance emerging shortly after stimulus onset and sustaining throughout information processing. These findings suggest that oscillatory alpha activity and aperiodic neural dynamics show differential sensitivity to distinct attentional abnormalities in ADHD, with alpha oscillations primarily reflecting demand-related regulatory deficits and aperiodic activity primarily reflecting distractor-related neural instability.

neuroscience↗

Pharmacological targeting of EED is an effective therapeutic strategy in cellular models of incurable neuroendocrine prostate cancer

BackgroundNeuroendocrine Prostate Cancer (NEPC) is an incurable malignancy, originating from the trans-differentiation of prostate adenocarcinoma (PRAD). Compared to PRAD, NEPC shows over-activation of Polycomb Repressive complex-1(PRC1) and-2 (PRC2), which are multiprotein epigenetic writers that drive cancer progression via tumour suppressor gene silencing. Tazemetostat is a PRC2 inhibitor approved for the treatment of sarcomas and lymphomas. ORIC-944 is a novel EED (Embryonic Ectoderm Development) inhibitor, which is being tested in clinical trials. EED is an attractive target as it functions as a key component of both PRC1 and PRC2. Objective and MethodsWe compared the anticancer effects of tazemetostat and ORIC-944 in NEPC and PRAD cells. Cells were exposed to various concentrations of the two compounds to measure effects on cell viability (IC50) and apoptosis (flow cytometry). PRC2 inhibition was confirmed by measuring histone H3 Lys 27 trimethylation (H3K27me3) via ELISA and Western Blot. RNA Sequencing and pathway analysis was conducted to study modes of actions of tazemetostat vs ORIC-944. ResultsUnlike tazemetostat, ORIC-944 causes dose-dependent growth inhibition in both NEPC and PRAD cells. In this context, EED targeting achieves IC50 values that are comparable to those of compounds used for the clinical treatment of advanced prostate cancer. Moreover, ORIC-944 (but not tazemetostat) causes significant apoptosis in NEPC cells. Both tazemetostat and ORIC-944 reduce H3K27me3. Mechanistically, both compounds reactivate the expression of known PRC2 targets, such as genes that control neural differentiation. However, the EED inhibitor also reactivates PRC1 targets, including pro-apoptotic and anti-proliferating genes (e.g. metallothionines). This evidence suggests that EED inhibition is a promising therapeutic strategy for NEPC.

cancer biology↗

Interdependence of a kinase and its cognate substrate plasma membrane nanoscale dynamics underlies Arabidopsis response to viral infection

Plant viruses represent a risk to agricultural production and as only a few treatments exist, it is urgent to identify resistance mechanisms and factors. In plant immunity, plasma membrane (PM)-localized proteins play an essential role in sensing the extracellular threat presented by bacteria, fungi or herbivores. Viruses are intracellular pathogens and as such the role of the plant PM in detection and resistance against viruses is often overlooked. We investigated the role of the partially PM-bound Calcium-dependent protein kinase 3 (CPK3) in viral infection and we discovered that it displayed a specific ability to hamper viral propagation over CPK isoforms that are involved in immune response to extracellular pathogens. More and more evidence support that the lateral organization of PM proteins and lipids underlies signal transduction in plants. We showed here that CPK3 diffusion in the PM is reduced upon activation as well as upon viral infection and that such immobilization depended on its substrate, Remorin (REM1.2), a scaffold protein. Furthermore, we discovered that the viral infection induced a CPK3-dependent increase of REM1.2 PM diffusion. Such interdependence was also observable regarding viral propagation. This study unveils a complex relationship between a kinase and its substrate that contrasts with the commonly described co-stabilisation upon activation while it proposes a PM-based mechanism involved in decreased sensitivity to viral infection in plants.

plant biology↗

Keratinocyte-tethering modification for biologics enables location-precise treatment in mouse vitiligo

Despite the central role of IFN{gamma} in vitiligo pathogenesis, systemic IFN{gamma} neutralization is an impractical treatment option due to strong immunosuppression. However, most vitiligo patients present with less than 20% affected body surface area, which provides an opportunity for localized treatments that avoid systemic side effects. After identifying keratinocytes as key cells that amplify IFN{gamma} signaling during vitiligo, we hypothesized that tethering an IFN{gamma} neutralizing antibody to keratinocytes would limit anti-IFN{gamma} effects to the treated skin for the localized treatment. To that end, we developed a bispecific antibody (BsAb) capable of blocking IFN{gamma} signaling while binding to desmoglein expressed by keratinocytes. We characterized the effect of the BsAb in vitro, ex vivo, and in a mouse model of vitiligo. SPECT/CT biodistribution and serum assays after local footpad injection revealed that the BsAb had improved skin retention, faster elimination from the blood, and less systemic IFN{gamma} inhibition than the non-tethered version. Furthermore, the BsAb conferred localized protection almost exclusively to the treated footpad during vitiligo that was not possible by local injection of the non-tethered anti-IFN{gamma} antibody. Thus, keratinocyte-tethering proved effective while significantly diminishing off-tissue effects of IFN{gamma} blockade, offering a new treatment strategy for localized skin diseases, including vitiligo.

immunology↗

Overexpression of NDR1 Leads to Pathogen Resistance at Elevated Temperatures

Abiotic and biotic environments influence a myriad of plant-related processes, including growth, development, and the establishment and maintenance of interaction(s) with microbes. As a driver of this signaling between plants and microbes, the role of plant hormones in both surveillance and signaling has emerged as a point of intersection between plant-abiotic and -biotic responses. In the current study, we elucidate a role for NON-RACE-SPECIFIC DISEASE RESISTANCE1 (NDR1) by exploiting effector-triggered immunity (ETI) to define the regulation of plant host immunity in response to both pathogen infection and elevated temperature. We generated time-series RNA sequencing data of WT Col-0, a NDR1 overexpression line, as well as ndr1 and ics1-2 mutant plants under elevated temperature. Not surprisingly, the NDR1-overexpression line showed genotype-specific gene expression changes related to defense response and immune system function. Interestingly, overexpression of NDR1 revealed a role for NDR1 in immune system function; specifically, we describe a mechanism that intersects with Pseudomonas syringae, type-III effector translocation, R-protein signaling complex stabilization, and sustained levels of SA at elevated temperature during ETI. The results described herein support a role for NDR1 in maintaining cell signaling during simultaneous exposure to elevated temperature and avirulent pathogen stressors. One-sentence summaryNDR1 is required for Pst-AvrRpt2 triggered ETI at elevated temperature.

plant biology↗

NDR1 and the Arabidopsis Plasma Membrane ATPase AHA5 are Required for Processes that Converge on Drought Tolerance and Immunity

NON-RACE-SPECIFIC DISEASE RISISTANCE1 (NDR1) is a key component of plant immune signaling, required for defense against the bacterial pathogen Pseudomonas syringae. Plant stress responses have overlapping molecular, physiological, and cell biology signatures, and given the central role of NDR1 during biotic stress perception and signaling, we hypothesized that NDR1 also functions in abiotic stress responses, including in a role that mediates signaling at the plasma membrane (PM) - cell wall (CW) continuum. Here, we demonstrate that NDR1 is required for the induction of drought stress responses in plants, a role that couples stress signaling in an abscisic acid-dependent manner. We show that NDR1 physically associates with the PM-localized H+-ATPases AHA1, AHA2, and AHA5 and is required for proper regulation of H+-ATPase activity and stomatal guard cell dynamics, providing a mechanistic function of NDR1 during drought responses. In the current study, we demonstrate that NDR1 functions in signaling processes associated with both biotic and abiotic stress response pathways, a function we hypothesize represents NDR1s role in the maintenance of cellular homeostasis during stress. We propose a role for NDR1 as a core transducer of signaling between cell membrane processes and intercellular stress response activation.

plant biology↗

CD4 T cell help prevents CD8 T cell exhaustion and promotes control of Mycobacterium tuberculosis infection

CD4 T cells are essential for immunity to tuberculosis because they produce cytokines including interferon-{gamma}. Whether CD4 T cells act as "helper" cells to promote optimal CD8 T cell responses during Mycobacterium tuberculosis is unknown. Using two independent models, we show that CD4 T cell help enhances CD8 effector functions and prevents CD8 T cell exhaustion. We demonstrate synergy between CD4 and CD8 T cells in promoting the survival of infected mice. Purified helped, but not helpless, CD8 T cells efficiently restrict intracellular bacterial growth in vitro. Thus, CD4 T cell help plays an essential role in generating protective CD8 T cell responses against M. tuberculosis infection in vitro and in vivo. We infer vaccines that elicit both CD4 and CD8 T cells are more likely to be successful than vaccines that elicit only CD4 or CD8 T cells.

immunology↗

Correlation of p53 and DNA repair gene mutation patterns in human malignancies indicates different tumour suppression mechanisms of p53

P53 suppresses tumorigenesis through multiple cellular functions/mechanisms. Recently, Janic A, et al. reported that DNA repair pathways are critical mediators of p53-dependent tumor suppression. We showed, by mining cBioPortal data of a range of human cancers, that the tendency of mutual exclusivity of mutations in p53 and DNA repair genes only exist in very limited human cancer types. In the majority of human cancers, p53 mutations are equally distributed between DNA repair gene mutation positive and negative cases and in a number of human cancers, p53 and DNA repair gene mutations have a tendency of co-occurrence. These different correlation patterns of p53 and DNA repair gene mutations in human malignancies may reflect different critical molecular/cellular pathways activated by p53 in different organs or cell types to suppress tumorigenesis.

cancer biology↗