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

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.

SUBMITTER: Wu CY

PROVIDER: S-EPMC3124582 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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

Wu Chia-Yen CY Curtis Amelia A Choi Yong Seok YS Maeda Miho M Xu Mary Jue MJ Berg Amanda A Joneja Upasana U Mason Robert W RW Lee Kelvin H KH Wang Wenlan W

Biochimica et biophysica acta 20110505 9

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 ...[more]

PMID: 21609790

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