Biology subjects

Benachour, A.

Publications and source records attributed to Benachour, A..

3 recordsLinked to original sources

bioRxiv2026

SERCA is a host target of the SARS-CoV-2 envelope protein linking calcium homeostasis to autophagy

The SARS-CoV-2 envelope (E) protein is a virulence factor that remodels host endomembranes, but mechanisms remain incompletely understood. We recently demonstrated that E protein interacts with and inhibits the sarco/endoplasmic reticulum Ca2-ATPase (SERCA), disrupting ER calcium homeostasis. Here, we investigated how this perturbation affects autophagy-associated membrane organization. E protein expression induced lipidated LC3 accumulation and enlarged p62-positive structures, consistent with dysregulated autophagic turnover. Although E protein partially colocalized with LC3 and p62, enlarged p62-positive structures were also observed in cells retaining the reticular ER distribution of E protein, indicating that their formation does not require association with E protein or ER reorganization. E protein also increased the association of p62-positive structures with lysosomes without altering lysosome abundance. Pharmacological SERCA activation attenuated E protein-induced remodeling of autophagy-associated structures, demonstrating that SERCA inhibition contributes to these alterations. Together, our findings establish SERCA-dependent ER calcium homeostasis as a host pathway linking E protein expression to remodeling of autophagy-associated membrane compartments, providing a mechanistic framework for how the SARS-CoV-2 E protein promotes ER membrane remodeling associated with coronavirus replication.

cell biology↗

bioRxiv2025

Motor Imagery Affects both Cortical and Spinal Circuitry: A Transcranial and Transspinal Magnetic Stimulation Study.

Motor imagery (MI), the mental rehearsal of movement without physical execution, is a key technique in brain-computer interfaces (BCIs) for voluntarily eliciting cortical modulations. Beyond cortical effects, MI could also modulate spinal cord processing, which offers additional potential for neurorehabilitation in conditions like spinal cord injury (SCI) and stroke, where BCIs are used for therapy. To investigate the interactions of MI with both the cortex and the spinal cord, we employed both transcranial magnetic stimulation (TMS) and trans-spinal magnetic stimulation (TSMS). With proper coil orientation, TSMS elicited short- and long-latency motor evoked potentials (MEPs) in forearm muscles and lateralized evoked potentials in the cortex. MI modulated both TMS-induced and TSMS-induced cortical responses and MEPs. This demonstration of MI affecting both cortical and spinal circuitry underscores its potential as a powerful strategy for BCI-driven neurorehabilitation, including pairing MI with magnetic stimulation.

neuroscience↗

bioRxiv2025

Cardiac activity impacts spinal cord excitability. A Call to Return to the Roots

The heart continuously shapes neural processing and behavior through cardiac-brain interactions. While cortical excitability fluctuations and their role in cardiac-dependent cognitive and sensorimotor phenomena have been extensively studied, the temporal dynamics and contribution of spinal excitability oscillations across the cardiac cycle remain poorly characterized. In this study, we examine whether motor evoked potentials elicited by magnetic stimulation of the spinal cord are modulated by the cardiac cycle phase in healthy participants. Real-time adapting ECG-triggered stimulation enabled precise targeting of five phases across the cardiac cycle. Spinal excitability was significantly phase-dependent, with MEPs peaking during late diastole. MEPs amplitude was also found to be modulated by preceding cardiac intervals, where shorter intervals predict stronger diastolic facilitation. These findings establish that spinal excitability is rhythmically modulated by the cardiac cycle, potentially through blood pressure-mediated mechanisms. Notably, the diastolic facilitation observed here contrasts with previously reported motor cortex excitability profiles, indicating a non-synchronous cardiac modulation of spinal versus cortical excitability. These results may benefit neuromodulation approaches for motor and psychiatric disorder treatment and emphasize the critical importance of including spinal measures in future heart-brain interaction studies.

neuroscience↗