Science China-Chemistry
·
2018
·Vol. 61
·期 4
·412-417
·
IF 4.448
Si Yanyan,Liang Lujun,Tang Shan,Qi Yunkun,Huang Yong,Liu Lei
Ubiquitin (Ub) chain isopeptide bond mimics are useful molecules for biochemical and biophysical studies. Herein, we report the semi-synthesis of the disulfide-linked K11/K48-branched tri-Ub (Ub 3 11/48 (S–S)), the first example of an isopeptide mimic for the branched Ub chains, which have recently emerged as an interesting category of Ub modifications. Our strategy comprised the E1-dependent synthesis of the Ub conjugate of aminoethanethiol, followed by disulfide formation with Ub(K11C, K48C). The structure of the synthetic isopeptide bond mimics was verified by the crystal structure of Ub 3 11/48 (S–S). Deubiquitination and pulldown assays indicated that the synthetic Ub 3 11/48 (S–S) could be hydrolyzed by linkage-specific deubiquitinases (K11-specific Cezanne and K48-specific OTUB1), and recognized by proteasomal ubiquitin receptor S5a.
研究领域:
生物化学
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分子生物学
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DOI
高影响因子
Autophagy
·
2023
·
IF 13.3
Chaonan Sun,Yuxin Chen,Qianqian Gu,Yuanyuan Fu,Yao Wang,Cui Liu,Huazhong Xie,Yong Liao,Zhihua Zheng,Peiqing Liu,Min Li
ATG4B is a core protein and essential for cleaving precursor MAP1LC3/LC3 or deconjugating lipidated LC3-II to drive the formation of autophagosomes. The protein stability and activity of ATG4B regulated by post-translational modification (ubiquitination) will directly affect macroautophagy/autophagy. However, the mechanism involved in ATG4B ubiquitination is largely unclear. In this study, a new E3 ligase of ATG4B, UBE3C, was identified by mass spectra. UBE3C mainly assembles K33-branched ubiquitin chains on ATG4B at Lys119 without causing ATG4B degradation. In addition, the increased ubiquitination of ATG4B caused by UBE3C overexpression inhibits autophagy flux in both normal and starvation conditions, which might be due to the reduced activity of ATG4B and ATG4B-LC3 interaction. This reduction could be reversed once the lysine 119 of ATG4B was mutated to arginine. More important, under starvation conditions the interaction between ATG4B and UBE3C apparently decreased followed by the removal of the K33-branched ubiquitin chain of ATG4B. Thus, starvation-induced autophagy could be partially suppressed by an increased ubiquitination level of ATG4B. In conclusion, our research reveals a novel modification mode of ATG4B in which UBE3C can fine tune ATG4B activity by specific ubiquitination regulating autophagy without causing ATG4B degradation.
研究领域:
细胞生物学
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分子生物学
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生物化学
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DOI
PubMed
高影响因子
LABORATORY INVESTIGATION
·
2024
·
IF 5.1
Jianfeng Yi,Weilong Qu,Xinkun Huang,Guangze Zhang,Hanxu Gao,Jiancheng He,Wanjiang Xue
E3 ubiquitin ligases, crucial enzymes in the ubiquitination pathway, significantly influence the development of malignant tumors, including gastric cancer (GC), by regulating the stability of oncogenic and tumor-suppressive proteins. This study employed bioinformatics analysis of public databases alongside various experimental techniques—tissue arrays, qRT-PCR, Western blot, immunofluorescence, and co-immunoprecipitation—to identify and explore the role of HECW1, a pivotal NEDD4 family E3 ubiquitin ligase, in GC progression. Results demonstrated that HECW1 is markedly overexpressed in GC tissues relative to normal gastric tissues, and its elevated expression correlates with poor prognosis in GC patients. In vitro experiments revealed that HECW1 overexpression significantly enhances the metastatic capabilities of GC cells. Mechanistically, HECW1 interacts with HIPK2 to facilitate its ubiquitination and degradation, thereby activating AKT and promoting the expression of downstream epithelial mesenchymal transition related genes. In vivo experiments confirmed HECW1’s role in promoting GC cell metastasis, highlighting the HECW1-HIPK2-AKT signaling axis as critical in GC metastasis. These findings not only elucidate a novel metastasis mechanism of GC but also suggest potential molecular targets for developing new therapeutic strategies against GC.
研究领域:
肿瘤学
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分子生物学
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癌症研究
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DOI
PubMed
高影响因子
EMBO REPORTS
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2025
·
IF 6.2
LiXiao-Hu,WangMeng,XuYi-Ran,GuoQian-Huan,LiuPeng,WuChang-Ai,YangGuo-Dong,HuangJin-Guang,ZhangShi-Zhong,ZhengCheng-Chao,YanKang
Drought stress significantly impacts plant growth and productivity, requiring complex adaptive responses to ensure survival. In eukaryotes, autophagy and the ubiquitin-proteasome system (UPS) are critical pathways for maintaining cellular homeostasis under stress. While their interaction is well-studied in animals, it remains poorly understood in plants, particularly under drought conditions. Here, we identify the E3 ubiquitin ligase SRAS1.1 as a key regulator of selective autophagy and drought tolerance in Arabidopsis, mediating its function through the ubiquitination and degradation of the autophagy receptor DSK2A. Loss of SRAS1.1 enhances drought tolerance by reducing water loss, increasing survival rates, and accelerating flowering. SRAS1.1 directly interacts with and ubiquitinates the autophagy receptor DSK2A, promoting its degradation via the 26S proteasome. Notably, under drought stress, SRAS1.1 relocates from the nucleus to the cytoplasm, associates with autophagosomes, and modulates autophagy-related gene expression and BES1 accumulation. These findings provide novel insights into UPS-autophagy crosstalk in plants and highlight SRAS1.1 as a promising target for genetic engineering to develop drought-resilient crops and to advance sustainable agriculture.
研究领域:
植物生物学
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分子生物学
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遗传学
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生物化学
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逆境生理学
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产品关联
DOI
PubMed
高影响因子
DEVELOPMENT
·
2023
·Vol. 150
·期 10
·
IF 4.6
Zheng Huiwen,Zhang Xiaobo,Fu Jing,Xue Yifan,Chen Zhi,Yang Guobin,Chen YiPing,Chen Di,Yuan Guohua
Dentin is the major hard tissue of teeth formed by differentiated odontoblasts. How odontoblast differentiation is regulated remains enigmatic. Here, we report that the E3 ubiquitin ligase CHIP is highly expressed in undifferentiated dental mesenchymal cells and downregulated after differentiation of odontoblasts. Ectopic expression of CHIP inhibits odontoblastic differentiation of mouse dental papilla cells, whereas knockdown of endogenous CHIP has opposite effects. Chip ( Stub1 ) knockout mice display increased formation of dentin and enhanced expression of odontoblast differentiation markers. Mechanistically, CHIP interacts with and induces K63 polyubiquitylation of the transcription factor DLX3, leading to its proteasomal degradation. Knockdown of DLX3 reverses the enhanced odontoblastic differentiation caused by knockdown of CHIP. These results suggest that CHIP inhibits odontoblast differentiation by targeting its tooth-specific substrate DLX3. Furthermore, our results indicate that CHIP competes with another E3 ubiquitin ligase, MDM2, that promotes odontoblast differentiation by monoubiquitylating DLX3. Our findings suggest that the two E3 ubiquitin ligases CHIP and MDM2 reciprocally regulate DLX3 activity by catalyzing distinct types of ubiquitylation, and reveal an important mechanism by which differentiation of odontoblasts is delicately regulated by divergent post-translational modifications.
研究领域:
分子生物学
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发育生物学
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牙科科学
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DOI
PubMed
高影响因子
BIOLOGICAL PROCEDURES ONLINE
·
2024
·Vol. 26
·期 1
·1-18
·
IF 3.7
Meng Xiangchao,Chen Hongye,Tan Zhihui,Yan Weitao,Liu Yinfeng,Lv Ji,Han Meng
Abstract Breast cancer is the most common female malignancy worldwide. Ubiquitin-specific peptidase 53 (USP53) has been shown to exert cancer-suppressing functions in several solid tumors, but its role and the underlying mechanism in breast cancer has not been clearly elucidated. Therefore, we have carried out a series of detailed studies on this matter at the levels of bioinformatics, clinical tissue, cell function and animal model. We found that USP53 expression was downregulated in breast cancer specimens and was negatively correlated with the clinical stages. Gain- and loss-of-function experiments demonstrated USP53 inhibited proliferation, clonogenesis, cell cycle and xenograft growth, as well as induced apoptosis and mitochondrial damage of breast cancer cells. Co-immunoprecipitation data suggested that USP53 interacted with zinc finger MYND-type containing 11 (ZMYND11), and catalyzed its deubiquitination and stabilization. The 33–50 amino acid Cys-box domain was key for USP53 enzyme activity, but not essential for its binding with ZMYND11. The rescue experiments revealed that the anti-tumor role of USP53 in breast cancer cells was at least partially mediated by ZMYND11. Both USP53 and ZMYND11 were prognostic protective factors for breast cancer. USP53-ZMYND11 axis may be a good potential biomarker or therapeutic target for breast cancer, which can provide novel insights into the diagnosis, treatment and prognosis.
研究领域:
肿瘤学
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分子生物学
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细胞生物学
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癌症研究
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产品关联
DOI
PubMed
高影响因子
CELLULAR SIGNALLING
·
2023
·
IF 4.8
Haiyan Zhao,Fangfang Bi,Mengyuan Li,Yuhan Diao,Chen Zhang
RING finger protein 180 (RNF180), an E3 ubiquitin ligase, is thought to be a tumor suppressor gene. However, the detailed mechanism of its effect on ovarian cancer (OV) has not been elucidated. Importin 4 (IPO4) which belongs to transport protein is reported to have cancer-promoting effects on OV. Here, we explored the potential signaling pathways related to RNF180 and IPO4. It was first verified that RNF180 is downregulated and IPO4 is upregulated in OV. By overexpressing or knocking down RNF180 in OV cells, we confirmed that RNF180 inhibited the malignant behaviors of OV cells both in vitro and in vivo . Bioinformatics analysis and proteomics experiments found that RNF180 could interact with IPO4 and promote the degradation of IPO4 through ubiquitination. In addition, overexpression of IPO4 removed the inhibitory effect of RNF180 on OV. We subsequently found that IPO4 could bind to the oncogene Sex determining Region Y-box 2 (SOX2). Knockdown of IPO4 in OV cells decreased SOX2 protein level in nucleus and promoted cyclin-dependent kinase inhibitory protein-1 (p21) expression. Overexpression of RNF180 also inhibited the expression of SOX2 in nucleus. All these results indicated that RNF180 inhibited the nuclear translocation of SOX2 by promoting ubiquitination of IPO4, which ultimately promoted the expression of p21 and then suppressed the progression of OV. This study verified the tumor suppressor effect of RNF180 on OV, elucidated the mechanism of the molecule network related to RNF180 and IPO4 in OV and identified for OV.
研究领域:
肿瘤学
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分子生物学
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细胞生物学
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癌症研究
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2024
·Vol. 25
·期 5
·2817
·
IF 4.9
Gengchen Xie,Bo Lei,Zhijie Yin,Fei Xu,Xinghua Liu
Our previous study has reported that metastasis-associated protein 2 (MTA2) plays essential roles in tumorigenesis and aggressiveness of gastric cancer (GC). However, the underlying molecular mechanisms ofMTA2-mediated GC and its upstream regulation mechanism remain elusive. In this study, we identified a novel circular RNA (circRNA) generated from theMTA2gene (circMTA2) as a crucial regulator in GC progression. CircMTA2was highly expressed in GC tissues and cell lines, and circMTA2promoted the proliferation, invasion, and metastasis of GC cells both in vitro and in vivo. Mechanistically, circMTA2interacted with ubiquitin carboxyl-terminal hydrolase L3 (UCHL3) to restrainMTA2ubiquitination and stabilizeMTA2protein expression, thereby facilitating tumor progression. Moreover, circMTA2was mainly encapsulated and transported by exosomes to promote GC cell progression. Taken together, these findings uncover that circMTA2suppressesMTA2degradation by interacting with UCHL3, thereby promoting GC progression. In conclusion, we identified a cancer-promoting axis (circMTA2/UCHL3/MTA2) in GC progression, which paves the way for us to design and synthesize targeted inhibitors as well as combination therapies.Keywords:CircRNAs;MTA2;gastric cancer;UCHL3;ubiquitination
研究领域:
分子生物学
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肿瘤学
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细胞生物学
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产品关联
DOI
PubMed
高影响因子
ORGANIC & BIOMOLECULAR CHEMISTRY
·
2020
·Vol. 18
·期 42
·8709-8715
·
IF 3.412
Ling Xu,Yan Zhang,Yi-Ming Li,Xian-Fu Lu
As an autophagic adaptor, p62 specifically targets ubiquitinated proteins to an autophagosome for lysosomal degradation through a critical ubiquitin-associated (UBA) domain. Recent research studies reported that the Ser403 and Ser407 sites on the UBA domain were modified by phosphorylation, increasing the binding affinity between p62 and ubiquitin (Ub). However, the exact role of each phosphorylation site in the regulation of the UBA domain and Ub binding remains unclear. In this text, we applied total chemical synthesis to prepare four types of phosphorylated UBAs, among which the bisphosphorylated UBA was successfully synthesized via the pseudo-dipeptide unit and auxiliary-mediated hydrazide-based native chemical ligation (NCL). Isothermal titration calorimetry (ITC) assays showed that the phosphorylation at S407 enhanced the binding affinity between UBA and Ub, while that at S403 did not. It was suggested that phosphorylation at S407 might be important for promoting the interplay between the UBA domain and Ub, whereas phosphorylation at S403 was not directly involved in this interaction.
研究领域:
生物化学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2019
·
IF 4.745
Jian Fan,Yinshan Ye,Guochao Chu,Zhongping Zhang,Yao Fu,Yi-Ming Li,Jing Shi
Ubiquitin (Ub)-based fluorescent reagents are crucial to explore the activity of deubiquitinases (DUBs). Ub-Rho110-G is one of the preferred tools, whereas the current synthetic route is time-consuming. Here, we report a new semisynthetic strategy to produce Ub-Rho110-G through direct aminolysis of Boc-protected Ub-Mesna using bisglycyl-rhodamine 110. We also applied this strategy to synthesize active SUMO2-Rho110-G for the first time. Biochemical analysis demonstrated that semisynthetic Ub or SUMO-Rho110-G can be effectively used for the detection of the activity of DUBs or SUMO-specific enzymes.
研究领域:
生物化学
·
分子生物学
·
蛋白质组学
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产品关联
DOI
PubMed
高影响因子
PANCREATOLOGY
·
2023
·
IF 3.6
Xin Wu,Xin Zhang,Peng Liu,Yao Wang
Background Pancreatic cancer is a common digestive system cancer and one of the most lethal malignancies worldwide. Ataxin-3 (ATXN3) protein is a deubiquitinating enzyme implicated in the occurrence of diverse human cancers. The potential role of ATXN3 in pancreatic cancer still remains unclear. Methods ATXN3 was screened from differentially-upregulated genes of GSE71989, GSE27890 and GSE40098 datasets. The mRNA and protein levels of ATXN3 was evaluated in pancreatic cancer samples and cell lines. Through the gain- and loss-of-function experiments, the effects of ATXN3 on cell proliferation , migration and invasion were evaluated using cell counting kit-8 (CCK-8), 5-ethynyl-2′-deoxyuridine (EdU) staining, wound healing and Transwell assays. Subsequently, the interaction between ATXN3 and HDAC6 was confirmed using double immunofluorescence staining, co-immunoprecipitation (co-IP) and proximity ligation assay (PLA). The underlying mechanism of ATXN3 was determined by knockdown of HDAC6 in ATXN3-upregulated pancreatic cancer cells. The function of ATXN3 in vivo was verified through xenograft assay. Results High expression of ATXN3 was found in pancreatic cancer tissues. Increased ATXN3 expression dramatically promoted cell proliferation, migration, and invasion. The malignant phenotypes were suppressed in ATXN3-silenced pancreatic cancer cells. ATXN3 was proved to interact with HDAC6 and regulate its degradation through deubiquitination . Downregulation of HDAC6 inhibited ATXN3-induced development of pancreatic cancer cells through regulating the expression of PCNA, vimentin and E-cadherin. ATXN3 facilitated tumor growth of pancreatic cancer and increased HDAC6 expression in vivo . Conclusions This study confirmed that ATXN3 facilitated malignant phenotypes of pancreatic cancer via reducing the ubiquitination of HDAC6.
研究领域:
肿瘤学
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分子生物学
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细胞生物学
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产品关联
DOI
PubMed
高影响因子
NEOPLASIA
·
2020
·
IF 5.696
Qing Yu,Zhiguo Hu,Yanwen Shen,Yihan Jiang,Peichen Pan,Tingjun Hou,Zhen-Qiang Pan,Jing Huang,Yi Sun
Cullin-RING E3 ligase (CRL) is the largest family of E3 ubiquitin ligase, responsible for ubiquitylation of ∼20% of cellular proteins. CRL plays an important role in many biological processes, particularly in cancers due to abnormal activation. CRL activation requires neddylation, an enzymatic cascade transferring small ubiquitin-like protein NEDD8 to a conserved lysine residue on cullin proteins. Recent studies have validated that neddylation is an attractive anticancer target. In this study, we report the establishment of an Alpha-Screen-based high throughput screen (HTS) assay for in vitro CUL5 neddylation, and screened a library of 17,000 compounds including FDA approved drugs, natural products and synthetic drug-like small-molecule compounds. Gossypol, a natural compound derived from cotton seed, was identified as an inhibitor of cullin neddylation. Biochemical studies showed that gossypol blocked neddylation of both CUL5 and CUL1 through direct binding to SAG-CUL5 or RBX1-CUL1 complex, and CUL5-H572 plays a key role for gossypol binding. On cellular level, gossypol inhibited cullin neddylation in a variety of cancer cell lines and selectively caused accumulation of NOXA and MCL1, the substrates of CUL5 and CUL1, respectively, in multiple cancer cell lines. Combination of gossypol with specific MCL1 inhibitor synergistically suppress growth of human cancer cells. Our study revealed a previously unknown anti-cancer mechanism of gossypol with potential to develop a new class of neddylation inhibitors.
研究领域:
药理学
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肿瘤学
·
细胞生物学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）