• Molecules and Cells
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• 제43권3호
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• pp.203-214
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• 2020

Post-translational modifications play major roles in the stability, function, and localization of target proteins involved in the nervous system. The ubiquitin-proteasome pathway uses small ubiquitin molecules to degrade neuronal proteins. Deubiquitinating enzymes (DUBs) reverse this degradation and thereby control neuronal cell fate, synaptic plasticity, axonal growth, and proper function of the nervous system. Moreover, mutations or downregulation of certain DUBs have been found in several neurodegenerative diseases, as well as gliomas and neuroblastomas. Based on emerging findings, DUBs represent an important target for therapeutic intervention in various neurological disorders. Here, we summarize advances in our understanding of the roles of DUBs related to neurobiology.

• BMB Reports
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• 제52권3호
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• pp.181-189
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• 2019

Cancer remains a life-threatening disease and accounts for the major mortality rates worldwide. The practice of using biomarkers for early detection, staging, and customized therapy may increase cancer patients' survival. Deubiquitinating enzymes (DUBs) are a family of proteases that remove ubiquitin tags from proteins of interest undergoing proteasomal degradation. DUBs play several functional roles other than deubiquitination. One of the important roles of DUBs is regulation of tumor progression. Several reports have suggested that the DUB family members were highly-elevated in various cancer cells and tissues in different stages of cancer. These findings suggest that the DUBs could be used as drug targets in cancer therapeutics. In this review, we recapitulate the role of the DUB family members, including ubiquitin-specific protease, otubain protease, and important candidates from other family members. Our aim was to better understand the connection between DUB expression profiles and cancers to allow researchers to design inhibitors or gene therapies to improve diagnosis and prognosis of cancers.

• 생명과학회지
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• 제32권6호
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• pp.476-481
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• 2022

유비퀴틴화는 단백질 안정성 조절을 통해 진핵세포 내 광범위한 과정에서 주요한 역할을 한다. 이 과정에서 탈유비퀴틴화 효소인 deubiquitinating enzymes (DUBs)은 표적단백질의 유비퀴틴 혹은 ubiquitin-like proteins에 결합하여 표적단백질의 분해를 억제하는 기능을 한다. DUBs의 역할은 주로 암생물학에서 다루어져 왔으며, 이를 통해 다양한 암 치료용 DUBs 억제제가 개발 중인 상황이다. 한편, 최근의 연구는 이러한 DUBs가 비만, 당뇨, 지방간을 포함한 대사질환에서 주요한 역할을 할 수 있을 것이라고 보고했다. 대사질환의 발생 및 진행에 있어 각기 다른 종류의 DUBs는 양적 혹은 음적 조절 작용을 갖음을 제시하였다. DUBs는 세포 내 다양한 전사인자의 단백질 발현 등 조절함으로써 대사질환의 발생 및 진행에 기여할 수 있음 생체 내, 외 및 인간 조직을 활용한 연구에서 입증되었다. UCH, USP7 및 USP19는 지방세포의 분화, 체중 증가, 및 인슐린 저항성에 관련이 있음을 식이 혹은 유전자조작으로 인한 비만 유도 마우스에서 검증하였다. CYLD, USP4 및 USP18의 경우 지방간의 발생과 밀접한 관계를 갖는다고 보고되었으며 이는 경우에 따라 체중 변화를 동반한다. 종합적으로, 본 총설에서는 비만 및 이와 관련한 대사질환에서 DUBs의 역할에 대한 최신 연구 결과 및 동향에 대해 기술하였다. 또한 DUBs에 새로운 역할에 관한 기초지식 및 분자적메커니즘을 제공함으로써 궁극적으로는 DUBs가 대사질환의 새로운 유전자 타겟이 될 수 있음을 시사한다.

• Molecules and Cells
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• 제41권11호
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• pp.933-942
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• 2018

Traditionally, small-molecule or antibody-based therapies against human diseases have been designed to inhibit the enzymatic activity or compete for the ligand binding sites of pathological target proteins. Despite its demonstrated effectiveness, such as in cancer treatment, this approach is often limited by recurring drug resistance. More importantly, not all molecular targets are enzymes or receptors with druggable 'hot spots' that can be directly occupied by active site-directed inhibitors. Recently, a promising new paradigm has been created, in which small-molecule chemicals harness the naturally occurring protein quality control machinery of the ubiquitin-proteasome system to specifically eradicate disease-causing proteins in cells. Such 'chemically induced protein degradation' may provide unprecedented opportunities for targeting proteins that are inherently undruggable, such as structural scaffolds and other non-enzymatic molecules, for therapeutic purposes. This review focuses on surveying recent progress in developing E3-guided proteolysis-targeting chimeras (PROTACs) and small-molecule chemical modulators of deubiquitinating enzymes upstream of or on the proteasome.

• BMB Reports
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• 제41권6호
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• pp.435-443
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• 2008

Post-translational modifiers can alter the function of proteins in many different ways. The conjugation of ubiquitin (Ub) and ubiqutin-like modifiers (Ubls) to proteins has been shown to be especially crucial in regulating a variety of cellular processes including the cell cycle, growth control, quality control, localization and many more. It is a highly dynamic process and involves a number of enzymes called E1, E2 and E3. Ub and Ubls are removed from the target proteins by deubiquitinating enzymes (DUBs) or Ubl-specific proteases (ULPs), thereby deconjugation can act as an additional level of control over the ubiquitin-conjugation system. In addition, DUBs and ULPs are responsible for activating Ub and Ubls from their inactive corresponding precursor forms. Here we review recent progress in molecular details of these deconjugating enzymes of Ubls.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2003년도 제45차 추계학술대회
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• pp.147-148
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• 2003

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2173-2179
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• 2013

Ubiquitin carboxyl-terminal hydrolase 37 (UCH37, also called UCHL5), a member of the deubiquitinating enzymes, can suppress protein degradation through disassembling polyubiquitin from the distal subunit of the chain. It has been proved that UCH37 can be activated by proteasome ubiqutin chain receptor Rpn13 and incorporation into the 19S complex. UCH37, which has been reported to assist in the mental development of mice, may play an important role in oncogenesis, tumor invasion and migration. Further studies will allow a better understanding of roles in cell physiology and pathology, embryonic development and tumor formation, hopefully providing support for the idea that UCH37 may constitute a new interesting target for the development of anticancer drugs.

• BMB Reports
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• 제47권9호
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• pp.475-482
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• 2014

Ubiquitin (Ub) is a versatile signaling molecule that plays important roles in a variety of cellular processes. Cellular Ub pools, which are composed of free Ub and Ub conjugates, are in dynamic equilibrium inside cells. In particular, increasing evidence suggests that Ub homeostasis, or the maintenance of free Ub above certain threshold levels, is important for cellular function and survival under normal or stress conditions. Accurate determination of various Ub species, including levels of free Ub and specific Ub chain linkages, have become possible in biological specimens as a result of the introduction of the proteomic approach using mass spectrometry. This technology has facilitated research on dynamic properties of cellular Ub pools and has provided tools for in-depth investigation of Ub homeostasis. In this review, we have also discussed the consequences of the disruption of Ub pool dynamics and homeostasis via deletion of polyubiquitin genes or mutations of deubiquitinating enzymes. The common consequence was a reduced availability of free Ub and a significant impact on the function and viability of cells. These observations further indicate that the levels of free Ub are important determinants for cellular protection.

• BMB Reports
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• 제51권3호
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• pp.143-150
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• 2018

The Hippo signaling pathway plays an essential role in adult tissue homeostasis and organ size control. Abnormal regulation of Hippo signaling can be a cause for multiple types of human cancers. Since the awareness of the importance of the Hippo signaling in a wide range of biological fields has been continually grown, it is also understood that a thorough and well-rounded comprehension of the precise dynamics could provide fundamental insights for therapeutic applications. Several components in the Hippo signaling pathway are known to be targeted for proteasomal degradation via ubiquitination by E3 ligases. ${\beta}-TrCP$ is a well-known E3 ligase of YAP/TAZ, which leads to the reduction of YAP/TAZ levels. The Hippo signaling pathway can also be inhibited by the E3 ligases (such as ITCH) which target LATS1/2 for degradation. Regulation via ubiquitination involves not only complex network of E3 ligases but also deubiquitinating enzymes (DUBs), which remove ubiquitin from its targets. Interestingly, non-degradative ubiquitin modifications are also known to play important roles in the regulation of Hippo signaling. Although there has been much advanced progress in the investigation of ubiquitin modifications acting as regulators of the Hippo signaling pathway, research done to date still remains inadequate due to the sheer complexity and diversity of the subject. Herein, we review and discuss recent developments that implicate ubiquitin-mediated regulatory mechanisms at multiple steps of the Hippo signaling pathway.

• BMB Reports
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• 제54권12호
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• pp.592-600
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• 2021

Parkinson's disease (PD) is one of the most common neurodegenerative diseases in the elderly population and is caused by the loss of dopaminergic neurons. PD has been predominantly attributed to mitochondrial dysfunction. The structural alteration of α-synuclein triggers toxic oligomer formation in the neurons, which greatly contributes to PD. In this article, we discuss the role of several familial PD-related proteins, such as α-synuclein, DJ-1, LRRK2, PINK1, and parkin in mitophagy, which entails a selective degradation of mitochondria via autophagy. Defective changes in mitochondrial dynamics and their biochemical and functional interaction induce the formation of toxic α-synuclein-containing protein aggregates in PD. In addition, these gene products play an essential role in ubiquitin proteasome system (UPS)-mediated proteolysis as well as mitophagy. Interestingly, a few deubiquitinating enzymes (DUBs) additionally modulate these two pathways negatively or positively. Based on these findings, we summarize the close relationship between several DUBs and the precise modulation of mitophagy. For example, the USP8, USP10, and USP15, among many DUBs are reported to specifically regulate the K48- or K63-linked de-ubiquitination reactions of several target proteins associated with the mitophagic process, in turn upregulating the mitophagy and protecting neuronal cells from α-synuclein-derived toxicity. In contrast, USP30 inhibits mitophagy by opposing parkin-mediated ubiquitination of target proteins. Furthermore, the association between these changes and PD pathogenesis will be discussed. Taken together, although the functional roles of several PD-related genes have yet to be fully understood, they are substantially associated with mitochondrial quality control as well as UPS. Therefore, a better understanding of their relationship provides valuable therapeutic clues for appropriate management strategies.