Alterations in the Cerebellar (Phospho)Proteome of a Cyclic Guanosine Monophosphate (cGMP)-dependent Protein Kinase Knockout Mouse

作者:Corradini Eleonora; Vallur Raghavan; Raaijmakers Linsey M; Feil Susanne; Feil Robert; Heck Albert J R*; Scholten Arjen
来源:MOLECULAR & CELLULAR PROTEOMICS, 2014, 13(8): 2004-2016.
DOI:10.1074/mcp.M113.035154

摘要

The cyclic nucleotide cyclic guanosine monophosphate (cGMP) plays an important role in learning and memory, but its signaling mechanisms in the mammalian brain are not fully understood. Using mass-spectrometry-based proteomics, we evaluated how the cerebellum adapts its (phospho) proteome in a knockout mouse model of cGMP-dependent protein kinase type I (cGKI). Our data reveal that a small subset of proteins in the cerebellum (similar to 3% of the quantified proteins) became substantially differentially expressed in the absence of cGKI. More changes were observed at the phosphoproteome level, with hundreds of sites being differentially phosphorylated between wildtype and knockout cerebellum. Most of these phosphorylated sites do not represent known cGKI substrates. An integrative computational network analysis of the data indicated that the differentially expressed proteins and proteins harboring differentially phosphorylated sites largely belong to a tight network in the Purkinje cells of the cerebellum involving important cGMP/cAMP signaling nodes (e.g. PDE5 and PKARII beta) and Ca2+ signaling (e.g. SERCA3). In this way, removal of cGKI could be linked to impaired cerebellar long-term depression at Purkinje cell synapses. In addition, we were able to identify a set of novel putative (phospho) proteins to be considered in this network. Overall, our data improve our understanding of cerebellar cGKI signaling and suggest novel players in cGKI-regulated synaptic plasticity.

  • 出版日期2014-8