2026-04-29T12:23:09Zhttps://repisalud.isciii.es/rest/oai/request

oai:repisalud.isciii.es:20.500.12105/231032024-11-29T18:41:15Zcom_20.500.12105_2173com_20.500.12105_2051col_20.500.12105_19597

00925njm 22002777a 4500 dc Ibars, Eva author Codina-Fabra, Joan author Bellí, Gemma author Casas, Celia author Tarrés, Marc author Solé-Soler, Roger author Lorite, Neus P author Ximenez-Embun, Pilar author Muñoz, Javier author Colomina, Neus author Torres-Rosell, Jordi author 2023-05-30 Ubiquitination controls numerous cellular processes, and its deregulation is associated with many pathologies. The Nse1 subunit in the Smc5/6 complex contains a RING domain with ubiquitin E3 ligase activity and essential functions in genome integrity. However, Nse1-dependent ubiquitin targets remain elusive. Here, we use label-free quantitative proteomics to analyze the nuclear ubiquitinome of nse1-C274A RING mutant cells. Our results show that Nse1 impacts the ubiquitination of several proteins involved in ribosome biogenesis and metabolism that, importantly, extend beyond canonical functions of Smc5/6. In addition, our analysis suggests a connection between Nse1 and RNA polymerase I (RNA Pol I) ubiquitination. Specifically, Nse1 and the Smc5/6 complex promote ubiquitination of K408 and K410 in the clamp domain of Rpa190, a modification that induces its degradation in response to blocks in transcriptional elongation. We propose that this mechanism contributes to Smc5/6-dependent segregation of the rDNA array, the locus transcribed by RNA Pol I. Cell Rep . 2023 ;42(5):112463. 10.1016/j.celrep.2023.112463 2211-1247 Cell reports 37141096 https://hdl.handle.net/20.500.12105/23103 Ubiquitin proteomics identifies RNA polymerase I as a target of the Smc5/6 complex.