Focus
Focus on Ubiquitin
- Focus issue:
- April 2014 Volume 21, No 4
Editorial
Focus on Ubiquitin
Essential modifications - p289
doi:10.1038/nsmb.2811
Ubiquitin and ubiquitin-like proteins have central roles in regulating cellular processes and homeostasis. This Focus examines our understanding of the ubiquitination reaction and the mechanisms by which ubiquitin and related modifications affect protein and cellular functions.
Full Text - Essential modifications | PDF (346 KB) - Essential modifications
Commentaries
Focus on Ubiquitin
Ubiquitin sets the timer: impacts on aging and longevity - pp290 - 292
Éva Kevei & Thorsten Hoppe
doi:10.1038/nsmb.2806
Protein homeostasis is essential for cellular function, organismal growth and viability. Damaged and aggregated proteins are turned over by two major proteolytic routes of the cellular quality-control pathways: the ubiquitin-proteasome system and autophagy. For both these pathways, ubiquitination provides the recognition signal for substrate selection. This Commentary discusses how ubiquitin-dependent proteolytic pathways are coordinated with stress- and aging-induced signals.
Full Text - Ubiquitin sets the timer: impacts on aging and longevity | PDF (592 KB) - Ubiquitin sets the timer: impacts on aging and longevity
Focus on Ubiquitin
Plant ubiquitin ligases as signaling hubs - pp293 - 296
Nitzan Shabek & Ning Zheng
doi:10.1038/nsmb.2804
The past decade has witnessed an explosion in the identification of ubiquitin-ligase complexes as the missing receptors for important small-molecule hormones regulating plant growth and development. These breakthroughs were initiated by genetic approaches, with structural analysis providing mechanistic insights into how hormone perception and signaling are coupled to protein ubiquitination. Although there are still many unknowns, plants have imparted valuable lessons about the pharmacology of ubiquitin modification.
Full Text - Plant ubiquitin ligases as signaling hubs | PDF (771 KB) - Plant ubiquitin ligases as signaling hubs
Focus on Ubiquitin
Ubiquitin in inflammation: the right linkage makes all the difference - pp297 - 300
Jacob E Corn & Domagoj Vucic
doi:10.1038/nsmb.2808
The immune system must operate in an effective, precise and safe manner to defend against diverse pathogens while avoiding attacking the body itself and commensal bacteria. Inflammatory pathways mediated by NOD-like, Toll-like, RIG-I–like and tumor-necrosis-factor receptor families are tightly regulated by ubiquitination, especially by Lys63-linked and linear polyubiquitin chains. Here we discuss the human ubiquitin-mediated inflammatory signaling system, emphasizing the interactions and activities whose coordination ensures timely, accurate regulation of inflammatory responses.
Full Text - Ubiquitin in inflammation: the right linkage makes all the difference | PDF (1,526 KB) - Ubiquitin in inflammation: the right linkage makes all the difference
Reviews
Focus on Ubiquitin
New insights into ubiquitin E3 ligase mechanism - pp301 - 307
Christopher E Berndsen & Cynthia Wolberger
doi:10.1038/nsmb.2780
Ubiquitin E3 ligases catalyze the final step of the ubiquitination cascade, promoting the transfer of ubiquitin from the E2 to the substrate target. Recent structural and biochemical studies have given insights in the catalytic mechanisms of all three E3 ligase classes, discussed in this Review.
Abstract - New insights into ubiquitin E3 ligase mechanism | Full Text - New insights into ubiquitin E3 ligase mechanism | PDF (1,362 KB) - New insights into ubiquitin E3 ligase mechanism
Focus on Ubiquitin
Lysine-targeting specificity in ubiquitin and ubiquitin-like modification pathways - pp308 - 316
Francesca Mattiroli & Titia K Sixma
doi:10.1038/nsmb.2792
Ubiquitin (Ub) and ubiquitin-like (Ubl) modifications occur primarily on lysine residues of target proteins to stimulate downstream signals. This Review discusses our current knowledge of lysine specificity in Ub and Ubl targeting, with particular focus on the systems where a detailed mechanism of modification and downstream signaling has been validated biochemically.
Abstract - Lysine-targeting specificity in ubiquitin and ubiquitin-like modification pathways | Full Text - Lysine-targeting specificity in ubiquitin and ubiquitin-like modification pathways | PDF (1,097 KB) - Lysine-targeting specificity in ubiquitin and ubiquitin-like modification pathways
Focus on Ubiquitin
Two-way communications between ubiquitin-like modifiers and DNA - pp317 - 324
Helle D Ulrich
doi:10.1038/nsmb.2805
DNA metabolism is regulated by the ubiquitin and SUMO modifications, but DNA also influences whether and when these modifications occur. This Review describes the mutual interactions between DNA, ubiquitin and SUMO that occur in DNA-associated processes.
Abstract - Two-way communications between ubiquitin-like modifiers and DNA | Full Text - Two-way communications between ubiquitin-like modifiers and DNA | PDF (799 KB) - Two-way communications between ubiquitin-like modifiers and DNA
Focus on Ubiquitin
Cleaning up in the endoplasmic reticulum: ubiquitin in charge - pp325 - 335
John C Christianson & Yihong Ye
doi:10.1038/nsmb.2793
The ER-associated degradation (ERAD) pathway maintains protein homeostasis in the ER by retrotranslocating unwanted proteins to the cytosol for proteasomal degradation. This Review discusses the integral role of the ubiquitin system in ERAD, highlighting how the two pathways intertwine to facilitate transport across the ER membrane.
Abstract - Cleaning up in the endoplasmic reticulum: ubiquitin in charge | Full Text - Cleaning up in the endoplasmic reticulum: ubiquitin in charge | PDF (971 KB) - Cleaning up in the endoplasmic reticulum: ubiquitin in charge
Focus on Ubiquitin
Dynamic regulation of macroautophagy by distinctive ubiquitin-like proteins - pp336 - 345
Daniel J Klionsky & Brenda A Schulman
doi:10.1038/nsmb.2787
Whereas the proteasome degrades individual proteins modified with ubiquitin chains, autophagy degrades many proteins and organelles en masse. A pair of ubiquitin-like proteins, Atg8 and Atg12, regulate autophagy-mediated degradation in a manner completely distinct from that of ubiquitin in the proteasome pathway, as discussed in this Review.
Abstract - Dynamic regulation of macroautophagy by distinctive ubiquitin-like proteins | Full Text - Dynamic regulation of macroautophagy by distinctive ubiquitin-like proteins | PDF (14,370 KB) - Dynamic regulation of macroautophagy by distinctive ubiquitin-like proteins