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Assaf, L.

Publications and source records attributed to Assaf, L..

2 recordsLinked to original sources

The encoding of interoceptive-based predictions by the paraventricular nucleus of the thalamus D2+ neurons

Understanding how the brain integrates internal physiological states with external sensory cues to guide behavior is a fundamental question in neuroscience. This process relies on interoceptive predictions, which are internal models that anticipate changes in the bodys physiological state based on sensory inputs and prior experiences. Despite recent advances in identifying the neural substrates of interoceptive predictions, the precise neuronal circuits involved remain elusive. In our study, we demonstrate that Dopamine 2 Receptor (D2R+) expressing neurons in the paraventricular nucleus of the thalamus (PVT) play key roles in interoception and interoceptive predictions. Specifically, these neurons are engaged in behaviors leading to physiologically relevant outcomes, with their activity highly dependent on the interoceptive state of the mice and the expected outcome. Furthermore, we show that chronic inhibition of PVTD2R+ neurons impairs the long-term performance of interoceptive-guided motivated behavior. Collectively, our findings provide insights into the role of PVTD2R+ neurons in learning and updating state-dependent predictions by integrating past experiences with current physiological conditions to optimize goal-directed behavior.

neuroscience↗

Architecture of Ca2+ tunneling, a basic Ca2+ signaling modality important for secretion

Ca2+ tunneling is a signaling modality that requires both Store-operated Ca2+ entry (SOCE) and Ca2+ release from the endoplasmic reticulum (ER). Tunneling expands the SOCE microdomain at ER-plasma membrane (PM) contact sites (ERPMCS) through Ca2+ uptake by the sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) into the ER lumen where it diffuses and is released via open inositol trisphosphate (IP3) receptors (IP3Rs). In this study using high resolution imaging, we outline the spatial remodeling of the Ca2+ tunneling machinery (IP3R1; SERCA; PMCA; and Ano1 as an effector) relative to STIM1 in response to store depletion. We show that store depletion leads to redistribution of these Ca2+ signaling modulators to distinct subdomains laterally at the PM and axially within the cortical ER. To functionally define the role of Ca2+ tunneling, we engineered a Ca2+ tunneling attenuator (CaTAr) that blocks tunneling without affecting Ca2+ release or SOCE. CaTAr inhibits Cl- secretion in sweat gland cells. Viral mediated expression of CaTAr in the mouse reduces sweating, showing that Ca2+ tunneling is important physiologically. Collectively our findings outline the architecture of the Ca2+ tunneling machinery and show that it is a fundamental physiological pertinent Ca2+ signaling modality.

cell biology↗