Abstract
Four nanobodies (VHH1-4SMT3) that target the yeast SUMO protein Smt3p were isolated and characterized. VHH1-4SMT3 bind to Smt3p and Smt3p-tagged proteins with high affinity (Kd: low nM). NMR analysis shows that the four nanobodies all bind near the C-terminus of Smt3p, partially overlapping with the binding site for the SUMO protease Ulp1p. Binding of Smt3p-specific nanobodies impairs Ulp1-mediated cleavage of Smt3p-tagged proteins, with VHH1SMT3 showing complete inhibition. The use of immobilized VHH2SMT3 enabled efficient purification of Smt3p-tagged proteins, while VHH1SMT3 can be used for immunoblotting and detects both Smt3p-tagged and free Smt3p. When expressed in yeast, VHH1SMT3 causes significant growth defects, particularly when targeted to the nucleus or fused with GFP, indicative of interference with essential SUMOylation-dependent processes.
Original language | English (US) |
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Article number | 18368 |
Journal | Scientific reports |
Volume | 15 |
Issue number | 1 |
DOIs | |
State | Published - Dec 2025 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- General