9EGV

HOIL-1 RING2 domain bound to ubiquitin

Summary for 9EGV

• Entry DOI: 10.2210/pdb9egv/pdb
• Descriptor: RanBP-type and C3HC4-type zinc finger-containing protein 1, Polyubiquitin-C, ZINC ION, ... (6 entities in total)
• Functional Keywords: rbr e3 ubiquitin ligase, enzyme-substrate complex, ring2 domain, ligase
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 3
• Total formula weight: 29798.58

Authors

Wang, X.S.,Lechtenberg, B.C. (deposition date: 2024-11-21, release date: 2024-12-11, Last modification date: 2025-04-16)

Primary citation

Wang, X.S.,Jiou, J.,Cerra, A.,Cobbold, S.A.,Jochem, M.,Mak, K.H.T.,Corcilius, L.,Silke, J.,Payne, R.J.,Goddard-Borger, E.D.,Komander, D.,Lechtenberg, B.C.
The RBR E3 ubiquitin ligase HOIL-1 can ubiquitinate diverse non-protein substrates in vitro.
Life Sci Alliance, 8:-, 2025

PubMed Abstract: HOIL-1 is a RING-between-RING-family E3 ubiquitin ligase and a component of the linear ubiquitin chain assembly complex. Although most E3 ubiquitin ligases conjugate ubiquitin to protein lysine sidechains, HOIL-1 has also been reported to ubiquitinate hydroxyl groups in protein serine and threonine sidechains and glucosaccharides, such as glycogen and its building block maltose, in vitro. However, HOIL-1 substrate specificity is currently poorly defined. Here, we show that HOIL-1 is unable to ubiquitinate lysine but can efficiently ubiquitinate serine and a variety of model and physiologically relevant di- and monosaccharides in vitro. We identify a critical catalytic histidine residue, His510, in the flexible catalytic site of HOIL-1 that enables this O-linked ubiquitination and prohibits ubiquitin discharge onto lysine sidechains. We use HOIL-1's in vitro non-proteinaceous ubiquitination activity to produce preparative amounts of different ubiquitinated saccharides that can be used as tool compounds and standards in the rapidly emerging field of non-proteinaceous ubiquitination. Finally, we report an engineered, constitutively active HOIL-1 variant that simplifies in vitro generation of ubiquitinated saccharides.

PubMed: 40169258
DOI: 10.26508/lsa.202503243

Experimental method

X-RAY DIFFRACTION (2 Å)