Orai1 Channels Are Essential for Amplification of Glutamate-Evoked Ca2+ Signals in Dendritic Spines to Regulate Working and Associative Memory

Store-operated Orai1 calcium channels function as highly Ca2+-selective ion channels and are broadly expressed in many tissues including the central nervous system, but their contributions to cognitive processing are largely unknown. Here, we report that many measures of synaptic, cellular, and behavioral models of learning are markedly attenuated in mice lacking Orai1 in forebrain excitatory neurons. Results with focal glutamate uncaging in hippocampal neurons support an essential role of Orai1 channels in amplifying NMDA-receptor-induced dendritic Ca2+ transients that drive activity-dependent spine morphogenesis and long-term potentiation at Schaffer collateral-CA1 synapses. Consistent with these signaling roles, mice lacking Orai1 in pyramidal neurons (but not interneurons) exhibit striking deficits in working and associative memory tasks. These findings identify Orai1 channels as essential regulators of dendritic spine Ca2+ signaling, synaptic plasticity, and cognition. [Display omitted] •Blockade of Orai1 activity impairs glutamate-evoked Ca2+ signals in dendritic spines of hippocampal neurons•Orai1 channels promote synaptic plasticity including LTP in the hippocampus•Deletion of Orai1 in excitatory neurons impairs working and associative memory•Orai1 channels amplify dendritic spine Ca2+ signals to regulate cognitive functions Ca2+ signals in dendritic spines are critical for synaptic plasticity and cognitive functions. Maneshi et al. show that store-operated Orai1 channels are essential for amplifying neurotransmitter-evoked Ca2+ signals in dendritic spines of mouse hippocampal neurons. This function of Orai1 is crucial for long-term potentiation and hippocampal-dependent learning and memory.