Dataset Information

Characterization of thiol-based redox modifications of Brassica napusSNF1-related protein kinase 2.6-2C.

ABSTRACT: Sucrose nonfermenting 1-related protein kinase 2.6 (SnRK2.6), also known as Open Stomata 1 (OST1) in Arabidopsis thaliana, plays a pivotal role in abscisic acid (ABA)-mediated stomatal closure. Four SnRK2.6 paralogs were identified in the Brassica napus genome in our previous work. Here we studied one of the paralogs, BnSnRK2.6-2C, which was transcriptionally induced by ABA in guard cells. Recombinant BnSnRK2.6-2C exhibited autophosphorylation activity and its phosphorylation sites were mapped. The autophosphorylation activity was inhibited by S-nitrosoglutathione (GSNO) and by oxidized glutathione (GSSG), and the inhibition was reversed by reductants. Using monobromobimane (mBBr) labeling, we demonstrated a dose-dependent modification of BnSnRK2.6-2C by GSNO. Furthermore, mass spectrometry analysis revealed previously uncharacterized thiol-based modifications including glutathionylation and sulfonic acid formation. Of the six cysteine residues in BnSnRK2.6-2C, C159 was found to have different types of thiol modifications, suggesting its high redox sensitivity and versatility. In addition, mBBr labeling on tyrosine residues was identified. Collectively, these data provide detailed biochemical characterization of redox-induced modifications and changes of the BnSnRK2.6-2C activity.

SUBMITTER: Ma T

PROVIDER: S-EPMC5881534 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Characterization of thiol-based redox modifications of Brassica napusSNF1-related protein kinase 2.6-2C.

Ma Tianyi T Yoo Mi-Jeong MJ Zhang Tong T Liu Lihong L Koh Jin J Song Wen-Yuan WY Harmon Alice C AC Sha Wei W Chen Sixue S

FEBS open bio 20180305 4

Sucrose nonfermenting 1-related protein kinase 2.6 (SnRK2.6), also known as Open Stomata 1 (OST1) in Arabidopsis thaliana, plays a pivotal role in abscisic acid (ABA)-mediated stomatal closure. Four SnRK2.6 paralogs were identified in the Brassica napus genome in our previous work. Here we studied one of the paralogs, BnSnRK2.6-2C, which was transcriptionally induced by ABA in guard cells. Recombinant BnSnRK2.6-2C exhibited autophosphorylation activity and its phospho ...[more]

PMID: 29632815

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Dataset Information

Characterization of thiol-based redox modifications of Brassica napusSNF1-related protein kinase 2.6-2C.

Publications

Characterization of thiol-based redox modifications of <i>Brassica napus</i>SNF1-related protein kinase 2.6-2C.

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