TY - JOUR
T1 - Deletion of CASK in mice is lethal and impairs synaptic function
AU - Atasoy, Deniz
AU - Schoch, Susanne
AU - Ho, Angela
AU - Nadasy, Krisztina A.
AU - Liu, Xinran
AU - Zhang, Weiqi
AU - Mukherjee, Konark
AU - Nosyreva, Elena D.
AU - Fernandez-Chacon, Rafael
AU - Missler, Markus
AU - Kavalali, Ege T.
AU - Südhof, Thomas C.
PY - 2007/2/13
Y1 - 2007/2/13
N2 - CASK is an evolutionary conserved multidomain protein composed of an N-terminal Ca2+/calmodulin-kinase domain, central PDZ and SH3 domains, and a C-terminal guanylate kinase domain. Many potential activities for CASK have been suggested, including functions in scaffolding the synapse, in organizing ion channels, and in regulating neuronal gene transcription. To better define the physiological importance of CASK, we have now analyzed CASK "knockdown" mice in which CASK expression was suppressed by ≈70%, and CASK knockout (KO) mice, in which CASK expression was abolished. CASK knockdown mice are viable but smaller than WT mice, whereas CASK KO mice die at first day after birth. CASK KO mice exhibit no major developmental abnormalities apart from a partially penetrant cleft palate syndrome. In CASK-deficient neurons, the levels of the CASK-interacting proteins Mints, Veli/ Mais, and neurexins are decreased, whereas the level of neuroligin 1 (which binds to neurexins that in turn bind to CASK) is increased. Neurons lacking CASK display overall normal electrical properties and form ultrastructurally normal synapses. However, glutamatergic spontaneous synaptic release events are increased, and GABAergic synaptic release events are decreased in CASK-deficient neurons. In contrast to spontaneous neurotransmitter release, evoked release exhibited no major changes. Our data suggest that CASK, the only member of the membrane-associated guanylate kinase protein family that contains a Ca 2+/calmodulin-dependent kinase domain, is required for mouse survival and performs a selectively essential function without being in itself required for core activities of neurons, such as membrane excitability, Ca 2+-triggered presynaptic release, or postsynaptic receptor functions.
AB - CASK is an evolutionary conserved multidomain protein composed of an N-terminal Ca2+/calmodulin-kinase domain, central PDZ and SH3 domains, and a C-terminal guanylate kinase domain. Many potential activities for CASK have been suggested, including functions in scaffolding the synapse, in organizing ion channels, and in regulating neuronal gene transcription. To better define the physiological importance of CASK, we have now analyzed CASK "knockdown" mice in which CASK expression was suppressed by ≈70%, and CASK knockout (KO) mice, in which CASK expression was abolished. CASK knockdown mice are viable but smaller than WT mice, whereas CASK KO mice die at first day after birth. CASK KO mice exhibit no major developmental abnormalities apart from a partially penetrant cleft palate syndrome. In CASK-deficient neurons, the levels of the CASK-interacting proteins Mints, Veli/ Mais, and neurexins are decreased, whereas the level of neuroligin 1 (which binds to neurexins that in turn bind to CASK) is increased. Neurons lacking CASK display overall normal electrical properties and form ultrastructurally normal synapses. However, glutamatergic spontaneous synaptic release events are increased, and GABAergic synaptic release events are decreased in CASK-deficient neurons. In contrast to spontaneous neurotransmitter release, evoked release exhibited no major changes. Our data suggest that CASK, the only member of the membrane-associated guanylate kinase protein family that contains a Ca 2+/calmodulin-dependent kinase domain, is required for mouse survival and performs a selectively essential function without being in itself required for core activities of neurons, such as membrane excitability, Ca 2+-triggered presynaptic release, or postsynaptic receptor functions.
KW - CaM kinase
KW - MAGUK
KW - Neurexin
KW - Neurotransmitter release
KW - Synapse
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U2 - 10.1073/pnas.0611003104
DO - 10.1073/pnas.0611003104
M3 - Article
C2 - 17287346
AN - SCOPUS:33847772666
SN - 0027-8424
VL - 104
SP - 2525
EP - 2530
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 7
ER -