Tomosyn interacts with the SUMO E3 ligase PIASγ

• Published in: PloS one Vol. 9; no. 3; p. e91697
• Main Authors: Geerts, Cornelia J, Jacobsen, Linda, van de Bospoort, Rhea, Verhage, Matthijs, Groffen, Alexander J A
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 10-03-2014; Public Library of Science (PLoS)
• Subjects: Amino acids; Animals; Biology; C-Terminus; Cell cycle; Cloning; Deoxyribonucleic acid; DNA; Ethylmaleimide - pharmacology; Gene expression; Genomics; HEK293 Cells; Humans; Immunoprecipitation; Kinases; Ligases; Male; Medical screening; Mice, Inbred BALB C; N-Terminus; Nerve Tissue Proteins - metabolism; Nervous system; Neurophysiology; Neurosciences; Neurotransmission; Phosphorylation; Physics; Poly-ADP-Ribose Binding Proteins; Protein binding; Protein Binding - drug effects; Protein Inhibitors of Activated STAT - metabolism; Proteins; R-SNARE Proteins - metabolism; Small Ubiquitin-Related Modifier Proteins - metabolism; SNAP receptors; Substrates; Sumo; Synaptic plasticity; Synaptogenesis; Syntaxin; Tomosyn; Two-Hybrid System Techniques; Ubiquitin; Ubiquitin-protein ligase; Ubiquitin-Protein Ligases - metabolism; Yeast
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0091697

Protein modification by Small Ubiquitin-like MOdifier (SUMO) entities is involved in a number of neuronal functions, including synaptogenesis and synaptic plasticity. Tomosyn-1 (syntaxin-binding protein 5; STXPB5) binds to t-SNARE (Soluble NSF Attachment Protein Receptor) proteins to regulate neurotransmission and is one of the few neuronal SUMO substrate proteins identified. Here we used yeast two-hybrid screening to show that tomosyn-1 interacts with the SUMO E3 ligase PIASγ (Protein Inhibitor of Activated STAT; PIAS4 or ZMIZ6). This novel interaction involved the C-terminus of tomosyn-1 and the N-terminus of PIASγ. It was confirmed by two-way immunoprecipitation experiments using the full-length proteins expressed in HEK293T cells. Tomosyn-1 was preferentially modified by the SUMO-2/3 isoform. PIASγ-dependent modification of tomosyn-1 with SUMO-2/3 presents a novel mechanism to adapt secretory strength to the dynamic synaptic environment.