Identification of the phosphorylation sites in the survival motor neuron protein by protein kinase A

TitleIdentification of the phosphorylation sites in the survival motor neuron protein by protein kinase A
Publication TypeJournal Article
Year of Publication2011
AuthorsWu, C. - Y., Curtis A., Choi Y. S., Maeda M., Xu M. J., Berg A., Joneja U., Mason R. W., Lee K. H., & Wang W.
JournalBiochimica et biophysica acta
Volume1814
Issue9
Pagination1134-9
Date Published2011 Sep
ISSN0006-3002
KeywordsAmino Acid Sequence; Computational Biology; Cyclic AMP-Dependent Protein Kinases; HEK293 Cells; Humans; Molecular Sequence Data; Phosphorylation; SMN Complex Proteins
Abstract

The survival motor neuron (SMN) protein plays an essential role in the assembly of uridine-rich small nuclear ribonuclear protein complexes. Phosphorylation of SMN can regulate its function, stability, and sub-cellular localization. This study shows that protein kinase A (PKA) phosphorylates SMN both in vitro and in vivo. Bioinformatic analysis predicts 12 potential PKA phosphorylation sites in human SMN. Mass spectrometric analysis of a tryptic digest of SMN after PKA phosphorylation identified five distinct phosphorylation sites in SMN (serines 4, 5, 8, 187 and threonine 85). Mutagenesis of this subset of PKA-phosphorylated sites in SMN affects association of SMN with Gemin2 and Gemin8. This result indicates that phosphorylation of SMN by PKA may play a role in regulation of the in vivo function of SMN.

DOI10.1016/j.bbapap.2011.04.015
Alternate JournalBiochim. Biophys. Acta
Refereed DesignationRefereed