scholarly journals Decoys provide a scalable platform for the genetic analysis of plant E3 ubiquitin ligases that regulate circadian clock function

2018 ◽  
Author(s):  
Ann Feke ◽  
Wei Liu ◽  
Jing Hong ◽  
Man-Wah Li ◽  
Chin-Mei Lee ◽  
...  
Keyword(s):  
Circadian Clock ◽  
Ubiquitin Ligase ◽  
E3 Ubiquitin Ligase ◽  
Ubiquitin Ligases ◽  
Gene Families ◽  
Dominant Negative ◽  
E3 Ubiquitin Ligases ◽  
Genetic Redundancy ◽  
Clock Period ◽  
Knock Out

ABSTRACTThe circadian clock in all eukaryotes relies on the regulated degradation of clock proteins to maintain 24-hour rhythmicity. Despite this knowledge, we know very few of the components that mediate degradation of proteins to control clock function. This is likely due to high levels of gene duplication and functional redundancy within plant E3 ubiquitin ligase gene families. In order to overcome this issue and discover E3 ubiquitin ligases that control circadian clock function, we generated a library of transgenic Arabidopsis lines expressing dominant-negative “decoy” E3 ubiquitin ligases. We determined their effects on the plant circadian clock and identified dozens of new potential regulators of circadian clock function. To demonstrate the potency of the decoy screening methodology to overcome genetic redundancy and identify bona fide clock regulators, we performed follow-up studies on PUB59 and PUB60. Using knock-out studies, we show that they redundantly control circadian clock period by regulating gene splicing. Furthermore, we confirm that they are part of a conserved protein complex that mediates splicing in eukaryotes. This work demonstrates the viability of E3 ubiquitin ligase decoys as a scalable screening platform to overcome traditional genetic challenges and discover E3 ubiquitin ligases that regulate plant developmental processes.

scholarly journals Decoys reveal the genetic and biochemical roles of redundant plant E3 ubiquitin ligases

2017 ◽  
Author(s):  
Chin-Mei Lee ◽  
Ann Feke ◽  
Christopher Adamchek ◽  
Kristofor Webb ◽  
José Pruneda-Paz ◽  
...  
Keyword(s):  
Circadian Clock ◽  
Mammalian Cells ◽  
E3 Ligase ◽  
Ubiquitin Ligases ◽  
E3 Ubiquitin Ligases ◽  
Genetic Redundancy ◽  
Clock Period ◽  
E3 Ligases ◽  
Wide Range

AbstractThe ubiquitin proteasome system (UPS) is the main cellular route for protein degradation in plants and is important for a wide range of biological processes including daily and seasonal timing. The UPS relies on the action of E3 ubiquitin ligases to specifically recognize substrate proteins and facilitate their ubiquitylation. In plants, there are three major challenges that inhibit studies of E3 ligase function: 1) rampant genetic redundancy, 2) labile interactions between an E3 ligase and its cognate substrates, and 3) a lack of tools for rapid validation of bona fide substrates. To overcome these 3 challenges, we have developed a decoy method that allows for rapid genetic analysis of E3 ligases, in vivo identification of substrates using immunoprecipitation followed by mass spectrometry, and reconstitution of the ubiquitylation reaction in mammalian cells to rapidly validate potential substrates. We employ the strategy to study the plant F-box proteins, ZTL, LKP2, and FKF1 revealing differential genetic impacts on circadian clock period and seasonal flowering. We identify a group of circadian clock transcriptional regulators that interact with ZTL, LKP2, and FKF1 in vivo providing a host of potential substrates that have not been seen previously. We then validate one substrate of ZTL, the plant circadian clock transcription factor CHE, and show that ZTL mediates CHE ubiquitylation and that the levels of the CHE protein cycle in daily timecourses. This work further untangles the complicated genetic roles of this family of E3 ligases and suggests that ZTL is a master regulator of a diverse set of critical clock transcription factors. Furthermore, the method that is validated here can be tool employed widely to overcome traditional challenges in studying redundant plant E3 ubiquitin ligases.

scholarly journals Decoys provide a scalable platform for the identification of plant E3 ubiquitin ligases that regulate circadian function

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Ann Feke ◽  
Wei Liu ◽  
Jing Hong ◽  
Man-Wah Li ◽  
Chin-Mei Lee ◽  
...  
Keyword(s):  
Circadian Clock ◽  
Ubiquitin Ligase ◽  
Transgenic Arabidopsis ◽  
Ubiquitin Ligases ◽  
Dominant Negative ◽  
E3 Ubiquitin Ligases ◽  
Clock Proteins ◽  
Bona Fide ◽  
Screening Platform

The circadian clock relies on regulated degradation of clock proteins to maintain rhythmicity. Despite this, we know few components that mediate protein degradation. This is due to high levels of functional redundancy within plant E3 ubiquitin ligase families. In order to overcome this issue and discover E3 ubiquitin ligases that control circadian function, we generated a library of transgenic Arabidopsis plants expressing dominant-negative ‘decoy’ E3 ubiquitin ligases. We determined their effects on the circadian clock and identified dozens of new potential regulators of circadian function. To demonstrate the potency of the decoy screening methodology to overcome redundancy and identify bona fide clock regulators, we performed follow-up studies on MAC3A (PUB59) and MAC3B (PUB60). We show that they redundantly control circadian period by regulating splicing. This work demonstrates the viability of ubiquitin ligase decoys as a screening platform to overcome genetic challenges and discover E3 ubiquitin ligases that regulate plant development.

scholarly journals Ubiquitination, Biotech Startups, and the Future of TRIM Family Proteins: A TRIM-Endous Opportunity

Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1015
Author(s):  
Utsa Bhaduri ◽  
Giuseppe Merla
Keyword(s):  
Drug Discovery ◽  
Protein Degradation ◽  
Ubiquitin Ligase ◽  
Genetic Disorders ◽  
E3 Ubiquitin Ligase ◽  
Ubiquitin Ligases ◽  
E3 Ubiquitin Ligases ◽  
Post Translational Modification ◽  
Disease Biology ◽  
The Future

Ubiquitination is a post-translational modification that has pivotal roles in protein degradation and diversified cellular processes, and for more than two decades it has been a subject of interest in the biotech or biopharmaceutical industry. Tripartite motif (TRIM) family proteins are known to have proven E3 ubiquitin ligase activities and are involved in a multitude of cellular and physiological events and pathophysiological conditions ranging from cancers to rare genetic disorders. Although in recent years many kinds of E3 ubiquitin ligases have emerged as the preferred choices of big pharma and biotech startups in the context of protein degradation and disease biology, from a surface overview it appears that TRIM E3 ubiquitin ligases are not very well recognized yet in the realm of drug discovery. This article will review some of the blockbuster scientific discoveries and technological innovations from the world of ubiquitination and E3 ubiquitin ligases that have impacted the biopharma community, from biotech colossuses to startups, and will attempt to evaluate the future of TRIM family proteins in the province of E3 ubiquitin ligase-based drug discovery.

scholarly journals A Decoy Library Uncovers U-Box E3 Ubiquitin Ligases That Regulate Flowering Time in Arabidopsis

Genetics ◽  
2020 ◽  
Vol 215 (3) ◽  
pp. 699-712 ◽  
Author(s):  
Ann M. Feke ◽  
Jing Hong ◽  
Wei Liu ◽  
Joshua M. Gendron
Keyword(s):  
Flowering Time ◽  
Development Program ◽  
Reproductive Development ◽  
Ubiquitin Ligases ◽  
Dominant Negative ◽  
E3 Ubiquitin Ligases ◽  
Genetic Redundancy ◽  
Bona Fide ◽  
Reverse Genetic Screen

Targeted degradation of proteins is mediated by E3 ubiquitin ligases and is important for the execution of many biological processes. Redundancy has prevented the genetic characterization of many E3 ubiquitin ligases in plants. Here, we performed a reverse genetic screen in Arabidopsis using a library of dominant-negative U-box-type E3 ubiquitin ligases to identify their roles in flowering time and reproductive development. We identified five U-box decoy transgenic populations that have defects in flowering time or the floral development program. We used additional genetic and biochemical studies to validate PLANT U-BOX 14 (PUB14), MOS4-ASSOCIATED COMPLEX 3A (MAC3A), and MAC3B as bona fide regulators of flowering time. This work demonstrates the widespread importance of E3 ubiquitin ligases in floral reproductive development. Furthermore, it reinforces the necessity of dominant-negative strategies for uncovering previously unidentified regulators of developmental transitions in an organism with widespread genetic redundancy, and provides a basis on which to model other similar studies.

scholarly journals Genome-wide analysis of HECT E3 ubiquitin ligase gene family in Solanum lycopersicum

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bhaskar Sharma ◽  
Harshita Saxena ◽  
Harshita Negi
Keyword(s):  
Gene Family ◽  
Ubiquitin Ligase ◽  
Plant Development ◽  
Stress Responses ◽  
E3 Ubiquitin Ligase ◽  
Ubiquitin Ligases ◽  
E3 Ubiquitin Ligases ◽  
E3 Ligases ◽  
Genome Wide Analysis ◽  
Genome Wide

AbstractThe E3 ubiquitin ligases have been known to intrigue many researchers to date, due to their heterogenicity and substrate mediation for ubiquitin transfer to the protein. HECT (Homologous to the E6-AP Carboxyl Terminus) E3 ligases are spatially and temporally regulated for substrate specificity, E2 ubiquitin-conjugating enzyme interaction, and chain specificity during ubiquitylation. However, the role of the HECT E3 ubiquitin ligase in plant development and stress responses was rarely explored. We have conducted an in-silico genome-wide analysis to identify and predict the structural and functional aspects of HECT E3 ligase members in tomato. Fourteen members of HECT E3 ligases were identified and analyzed for the physicochemical parameters, phylogenetic relations, structural organizations, tissue-specific gene expression patterns, and protein interaction networks. Our comprehensive analysis revealed the HECT domain conservation throughout the gene family, close evolutionary relationship with different plant species, and active involvement of HECT E3 ubiquitin ligases in tomato plant development and stress responses. We speculate an indispensable biological significance of the HECT gene family through extensive participation in several plant cellular and molecular pathways.

scholarly journals Expression Patterns and Functional Analysis of E3 Ubiquitin Ligase Genes in Rice

2021 ◽  
Author(s):  
huijuan zhang ◽  
Dewei Zheng ◽  
Fengming Song ◽  
Ming Jiang
Keyword(s):  
Ubiquitin Ligase ◽  
Abiotic Stresses ◽  
Magnaporthe Grisea ◽  
Function Analysis ◽  
Expression Patterns ◽  
E3 Ubiquitin Ligase ◽  
Ubiquitin Ligases ◽  
E3 Ubiquitin Ligases ◽  
Biotic And Abiotic Stresses ◽  
Genes Expression

Abstract Background: E3 ubiquitin ligases involve in many processes, containing the response to biotic and abiotic stresses. However, the functions of E3 ubiquitin ligases in rice were rarely studied.Results: In this research, 11 E3 ubiquitin ligase genes were selected and the function analysis was done in rice. These 11 E3 ubiquitin ligase genes showed different expression patterns under different treatments. The BMV:Os06g13870- infiltrated seedlings showed decreased resistance to Magnaporthe grisea (M. grisea) when compared with BMV:00-infiltrated seedlings, while BMV:Os04g34030- and BMV:Os02g33590-infiltrated seedlings showed increased resistance. They involved in the resistance against M. grisea maybe by regulating the accumulation of reactive oxygen species (ROS) and expression levels of defense-related genes. The BMV:Os06g34390-infiltrated seedlings showed decreased tolerance to drought stress while BMV:Os02g33590-infiltraed seedlings showed increased tolerance, maybe through regulating proline content, sugar content and drought-responsive genes’ expression. BMV:Os05g01940-infiltrated seedlings showed decreased tolerance to cold stress by regulating malondial dehyde (MDA) content and cold-responsive genes’ expression.Conclusion: These results showed that E3 ubiquitin ligases involved in the resistance to biotic and abiotic stresses in rice.

scholarly journals The Molecular and Pathophysiological Functions of Members of the LNX/PDZRN E3 Ubiquitin Ligase Family

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5938
Author(s):  
Jeongkwan Hong ◽  
Minho Won ◽  
Hyunju Ro
Keyword(s):  
Ubiquitin Ligase ◽  
E3 Ubiquitin Ligase ◽  
Ubiquitin Ligases ◽  
Ubiquitin Proteasome System ◽  
E3 Ubiquitin Ligases ◽  
Intercellular Signaling ◽  
Cellular Functions ◽  
Ring Type ◽  
Ubiquitin Ligase Activity ◽  
Ubiquitin Proteasome

The ligand of Numb protein-X (LNX) family, also known as the PDZRN family, is composed of four discrete RING-type E3 ubiquitin ligases (LNX1, LNX2, LNX3, and LNX4), and LNX5 which may not act as an E3 ubiquitin ligase owing to the lack of the RING domain. As the name implies, LNX1 and LNX2 were initially studied for exerting E3 ubiquitin ligase activity on their substrate Numb protein, whose stability was negatively regulated by LNX1 and LNX2 via the ubiquitin-proteasome pathway. LNX proteins may have versatile molecular, cellular, and developmental functions, considering the fact that besides these proteins, none of the E3 ubiquitin ligases have multiple PDZ (PSD95, DLGA, ZO-1) domains, which are regarded as important protein-interacting modules. Thus far, various proteins have been isolated as LNX-interacting proteins. Evidence from studies performed over the last two decades have suggested that members of the LNX family play various pathophysiological roles primarily by modulating the function of substrate proteins involved in several different intracellular or intercellular signaling cascades. As the binding partners of RING-type E3s, a large number of substrates of LNX proteins undergo degradation through ubiquitin-proteasome system (UPS) dependent or lysosomal pathways, potentially altering key signaling pathways. In this review, we highlight recent and relevant findings on the molecular and cellular functions of the members of the LNX family and discuss the role of the erroneous regulation of these proteins in disease progression.

scholarly journals New Discoveries on the Roles of “Other” HECT E3 Ubiquitin Ligases in Disease Development

2020 ◽  
Author(s):  
Emma I. Kane ◽  
Donald E. Spratt
Keyword(s):  
Ubiquitin Ligase ◽  
Developmental Disorders ◽  
E3 Ubiquitin Ligase ◽  
Ubiquitin Ligases ◽  
Disease Development ◽  
E3 Ubiquitin Ligases ◽  
Gene Encoding ◽  
Family Function ◽  
Substrate Proteins ◽  
Comprehensive Discussion

HECT E3 ubiquitin ligases selectively recognize, bind, and ubiquitylate their substrate proteins to target them for 26S proteasomal degradation. There is increasing evidence that HECT E3 ubiquitin ligase dysfunction due to misfolding and/or the gene encoding the protein being mutated is responsible for the development of different diseases. Apart from the more prominent and well-characterized E6AP and members of the NEDD4 family, new studies have begun to reveal how other members of the HECT E3 ubiquitin ligase family function as well as their links to disease and developmental disorders. This chapter provides a comprehensive discussion on the more mysterious members of the HECT E3 ubiquitin ligase family and how they control intracellular processes. Specifically, AREL1, HACE1, HECTD1, HECTD4, G2E3, and TRIP12 will be examined as these enzymes have recently been identified as contributors to disease development.

scholarly journals A Decoy Library Uncovers U-box E3 Ubiquitin Ligases that Regulate Flowering Time in Arabidopsis

2020 ◽  
Author(s):  
Ann M. Feke ◽  
Jing Hong ◽  
Wei Liu ◽  
Joshua M. Gendron
Keyword(s):  
Flowering Time ◽  
Ubiquitin Ligase ◽  
Floral Development ◽  
E3 Ubiquitin Ligase ◽  
Development Program ◽  
Ubiquitin Ligases ◽  
Biological Processes ◽  
E3 Ubiquitin Ligases ◽  
Developmental Transitions ◽  
Bona Fide

ABSTRACTTargeted degradation of proteins is mediated by E3 ubiquitin ligases and is important for the execution of many biological processes. Previously, we created and employed a large library of E3 ubiquitin ligase decoys to identify regulators of the circadian clock (Feke et al., 2019). In tandem with the screen for circadian regulators, we performed a flowering time screen using our U-box-type E3 ubiquitin ligase decoy transgenic library. We identified five U-box decoy transgenic populations that have defects in flowering time or the floral development program. We used additional genetic and biochemical studies to validate PLANT U-BOX 14 (PUB14), MOS4-ASSOCIATED COMPLEX 3A (MAC3A), and MAC3B as bona fide regulators of flowering time. This work reinforces the utility of the decoy library in identifying regulators of important developmental transitions in plants and expands the scope of the technique beyond our previous studies.

scholarly journals HaloTag-Targeted Sirtuin Rearranging Ligand (SirReal) for the Development of Proteolysis Targeting Chimeras (PROTACs) Against the Lysine Deacetylase Sirtuin 2 (Sirt2)

2020 ◽  
Author(s):  
Matthias Schiedel ◽  
Attila Lehotzky ◽  
Sándor Szunyogh ◽  
Judit Oláh ◽  
Sören Hammelmann ◽  
...  
Keyword(s):  
Protein Degradation ◽  
Small Molecule ◽  
Ubiquitin Ligase ◽  
E3 Ubiquitin Ligase ◽  
E3 Ligase ◽  
Ubiquitin Ligases ◽  
E3 Ubiquitin Ligases ◽  
Selective Inhibitors ◽  
E3 Ligases ◽  
Lysine Deacetylase

We have discovered the sirtuin rearranging ligands (SirReals) as a novel class of highly potent and selective inhibitors of the NAD+-dependent lysine deacetylase sirtuin 2 (Sirt2). In previous studies, conjugation of a SirReal with a ligand for the E3 ubiquitin ligase cereblon to form a so-called proteolysis targeting chimera (PROTAC), enabled small molecule-induced degradation of Sirt2. Here, we report the structure-based development of a chloroalkylated SirReal that induces the degradation of Sirt2 mediated by Halo-tagged E3 ubiquitin ligases. Using this orthogonal approach for Sirt2 degradation, we show that also other E3 ligases than cereblon, such as the E3 ubiquitin ligase parkin, can be harnessed for small molecule-induced Sirt2 degradation, thereby emphasizing the great potential of parkin to be utilized as an E3 ligase for new PROTACs approaches. Thus, our study provides new insights into targeted protein degradation in general and Sirt2 degradation in particular.

Sign in / Sign up

Export Citation Format

Share Document