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bioRxiv · 10.1101/2023.11.23.568317

Loss of neuronatin increases susceptibility of SERCA to thermal inactivation

Barfoot, M.·Fajardo, V.·Braun, J. L.
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Abstract

O_LIPhospholamban and sarcolipin are two key regulators of the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) that have been shown to protect SERCA from thermal inactivation in muscle C_LIO_LIWe have recently detected neuronatin (NNAT) in murine skeletal muscle and have shown that it too regulates SERCA C_LIO_LIHere, we questioned whether NNAT would also protect SERCA from thermal inactivation C_LIO_LIIn response to 60 min of heat stress at 40{degrees}C, maximal SERCA activity was significantly reduced in soleus homogenates obtained from NNAT knockout mice (-23%) but not wild-type mice (-5%). C_LIO_LIOur results add further support for NNATs role in regulating SERCA function in murine muscle C_LI

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Barfoot, M., Fajardo, V., Braun, J. L.. 2023-11-23. Loss of neuronatin increases susceptibility of SERCA to thermal inactivation. https://doi.org/10.1101/2023.11.23.568317

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