KDM2A Targets PFKFB3 for Ubiquitylation to Inhibit the Proliferation and Angiogenesis of Multiple Myeloma Cells

The lysine demethylase KDM2A (also known as JHDM1A or FBXL11) demethylates histone H3 at lysine K36 which lead to epigenetic regulation of cell proliferation and tumorigenesis. However, many biological processes are mediated by KDM2A independently by its histone demethylation activity. In the present study, we aimed to characterize the functional significance of KDM2A in multiple myeloma (MM) disease progression. Specifically, we defined that one of the key enzymes of glycolysis PFKFB3 (6-phosphofructo-2-kinase) is ubiquitylated by KDM2A which suppresses MM cell proliferation. Previous study showed that KDM2A and PFKFB3 promoted angiogenesis in various tumor cells. We further reveal that KDM2A targets PFKFB3 for ubiquitination and degradation to inhibit angiogenesis. Several angiogenic cytokines are also downregulated in MM. Clinically, MM patients with low KDM2A and high PFKFB3 levels have shown worse prognosis. These results reveal a novel function of KDM2A through ubiquitin ligase activity by targeting PFKFB3 to induce proliferation, glycolysis and angiogenesis in MM cells. The data provides a new potential mechanism and strategy for MM treatment.

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The ubiquitin ligase HERC4 mediates c-Maf ubiquitination and delays the growth of multiple myeloma xenografts in nude mice

Blood ◽

10.1182/blood-2015-07-658203 ◽

2016 ◽

Vol 127 (13) ◽

pp. 1676-1686 ◽

Cited By ~ 20

Author(s):

Zubin Zhang ◽

Jiefei Tong ◽

Xiaowen Tang ◽

Jiaxiang Juan ◽

Biyin Cao ◽

...

Keyword(s):

Multiple Myeloma ◽

Cell Proliferation ◽

Tumor Growth ◽

Ubiquitin Ligase ◽

Nude Mice ◽

Key Points

Key Points HERC4 is the first identified ubiquitin ligase that mediates c-Maf ubiquitination and degradation. HERC4 suppresses MM cell proliferation and delays MM tumor growth.

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Gfi1 ubiquitination and proteasomal degradation is inhibited by the ubiquitin ligase Triad1

Blood ◽

10.1182/blood-2006-11-058602 ◽

2007 ◽

Vol 110 (9) ◽

pp. 3128-3135 ◽

Cited By ~ 22

Author(s):

Jurgen A. F. Marteijn ◽

Laurens T. van der Meer ◽

Liesbeth van Emst ◽

Simon van Reijmersdal ◽

Willemijn Wissink ◽

...

Keyword(s):

Cell Proliferation ◽

Ubiquitin Ligase ◽

Ubiquitin Proteasome System ◽

Proteasomal Degradation ◽

Binding Domain ◽

U937 Cells ◽

Dna Binding Domain ◽

Protein Levels ◽

Ubiquitin Ligase Activity ◽

Ubiquitin Proteasome

Abstract Growth factor independence 1 (Gfi1) is a transcriptional repressor essential for the function and development of many different hematopoietic lineages. The Gfi1 protein expression is regulated by the ubiquitin-proteasome system. In granulocytes, Gfi1 is rapidly degraded by the proteasome, while it is more stable in monocytes. How the ubiquitination and degradation of Gfi1 is regulated is unclear. Here, we show that the ubiquitin ligase Triad1 interacts with the DNA-binding domain of Gfi1. Unexpectedly, we found that Triad1 inhibited Gfi1 ubiquitination, resulting in a prolonged half-life. Down-regulation of endogenous Triad1 by siRNAs resulted in increased Gfi1 ubiquitination. In U937 cells, Triad1 caused an increase in endogenous Gfi1 protein levels and slowed cell proliferation in a similar manner when Gfi1 itself was expressed. A Triad1 mutant that lacks the Gfi1-binding domain did not affect Gfi1 levels and proliferation. Because neither proteasome-ubiquitin nor Triad1 ubiquitin ligase activity was required for the inhibition of Gfi1 ubiquitination, these data suggest that Triad1 competes for Gfi1 binding with as yet to be identified E3 ubiquitin ligases that do mark Gfi1 for proteasomal degradation. The finetuning of Gfi1 protein levels regulated by Triad1 defines an unexpected role for this protein in hematopoiesis.

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Linear Ubiquitination Mediates EGFR-Induced NF-κB Pathway and Tumor Development

International Journal of Molecular Sciences ◽

10.3390/ijms222111875 ◽

2021 ◽

Vol 22 (21) ◽

pp. 11875

Author(s):

Fang Hua ◽

Wenzhuo Hao ◽

Lingyan Wang ◽

Shitao Li

Keyword(s):

Cell Proliferation ◽

Ubiquitin Ligase ◽

Tumor Development ◽

E3 Ubiquitin Ligase ◽

Growth Factor Receptor ◽

Ubiquitin Chain ◽

Plakophilin 2 ◽

Ubiquitin Ligase Activity ◽

Signaling Axis ◽

Differentiation And Proliferation

Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase that instigates several signaling cascades, including the NF-κB signaling pathway, to induce cell differentiation and proliferation. Overexpression and mutations of EGFR are found in up to 30% of solid tumors and correlate with a poor prognosis. Although it is known that EGFR-mediated NF-κB activation is involved in tumor development, the signaling axis is not well elucidated. Here, we found that plakophilin 2 (PKP2) and the linear ubiquitin chain assembly complex (LUBAC) were required for EGFR-mediated NF-κB activation. Upon EGF stimulation, EGFR recruited PKP2 to the plasma membrane, and PKP2 bridged HOIP, the catalytic E3 ubiquitin ligase in the LUBAC, to the EGFR complex. The recruitment activated the LUBAC complex and the linear ubiquitination of NEMO, leading to IκB phosphorylation and subsequent NF-κB activation. Furthermore, EGF-induced linear ubiquitination was critical for tumor cell proliferation and tumor development. Knockout of HOIP impaired EGF-induced NF-κB activity and reduced cell proliferation. HOIP knockout also abrogated the growth of A431 epidermal xenograft tumors in nude mice by more than 70%. More importantly, the HOIP inhibitor, HOIPIN-8, inhibited EGFR-mediated NF-κB activation and cell proliferation of A431, MCF-7, and MDA-MB-231 cancer cells. Overall, our study reveals a novel linear ubiquitination signaling axis of EGFR and that perturbation of HOIP E3 ubiquitin ligase activity is potential targeted cancer therapy.

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Linear Ubiquitination Mediates EGFR-Induced NF-kB Pathway and Tumor Development

10.20944/preprints202109.0394.v1 ◽

2021 ◽

Author(s):

Fang Hua ◽

Wenzhuo Hap ◽

Lingyan Wang ◽

Shitao Li

Keyword(s):

Cell Proliferation ◽

Ubiquitin Ligase ◽

Tumor Development ◽

E3 Ubiquitin Ligase ◽

Growth Factor Receptor ◽

Signaling Cascades ◽

Ubiquitin Ligase Activity ◽

Signaling Axis ◽

Epidermal Growth ◽

Differentiation And Proliferation

Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase that instigates several signaling cascades, including the NF-kB signaling pathway, to induce cell differentiation and proliferation. Overexpression and mutations of EGFR are found in up to 30% of solid tumors and correlate with a poor prognosis. Although it is known that EGFR-mediated NF-kB activation is involved in tumor development, the signaling axis is not well elucidated. Here, we found that PKP2 and the LUBAC complex were required for EGFR-mediated NF-kB activation. Upon EGF stimulation, EGFR recruited PKP2 to the plasma membrane, and PKP2 bridged HOIP, the catalytic E3 ubiquitin ligase in the LUBAC, to the EGFR complex. The recruitment activated the LUBAC complex and the linear ubiquitination of NEMO, leading to IkB phosphorylation and subsequent NF-kB activation. Furthermore, EGF-induced linear ubiquitination was critical for tumor cell proliferation and tumor development. Knockout of HOIP impaired EGF-induced NF-kB activity and reduced cell proliferation. HOIP knockout also abrogated the growth of A431 epidermal xenograft tumors in nude mice by more than 70%. More importantly, the HOIP inhibitor, HOIPIN-8, inhibited EGFR-mediated NF-kB activation and cell proliferation of A431, MCF-7, and MDA-MB-231 cancer cells. Overall, our study reveals a novel linear ubiquitination signaling axis of EGFR, and perturbation of HOIP E3 ubiquitin ligase activity is potential targeted cancer therapy.

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Structure of the HECT domain of human WWP2

Acta Crystallographica Section F Structural Biology Communications ◽

10.1107/s2053230x1501554x ◽

2015 ◽

Vol 71 (10) ◽

pp. 1251-1257 ◽

Cited By ~ 11

Author(s):

Wei Gong ◽

Xiaodan Zhang ◽

Wen Zhang ◽

Jie Li ◽

Ze Li

Keyword(s):

Stem Cells ◽

Immune Response ◽

Ubiquitin Ligase ◽

Embryonic Stem ◽

Crystallographic Analysis ◽

Molecular Replacement ◽

Biological Processes ◽

Hect Domain ◽

Ubiquitin Ligase Activity ◽

High Degree

WWP2 is a HECT-domain ubiquitin ligase of the Nedd4 family, which is involved in various important biological processes, such as protein degradation, membrane-protein sorting and transportation, the immune response, pluripotency of embryonic stem cells, tumourigenesis and metastasis. The HECT domain provides the intrinsic ubiquitin ligase activity of WWP2. Here, the expression, purification, crystallization and crystallographic analysis of the HECT domain of human WWP2 (HECTWWP2) are reported. HECTWWP2 has been crystallized and the crystals diffracted to 2.50 Å resolution. They belonged to space group P41212 and the structure has been solved via molecular replacement. The overall structure of HECTWWP2 has an inverted T-shape. This structure displays a high degree of conservation with previously published structures of Nedd4 subfamily members.

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The multi-subunit GID/CTLH E3 ubiquitin ligase promotes cell proliferation and targets the transcription factor Hbp1 for degradation

eLife ◽

10.7554/elife.35528 ◽

2018 ◽

Vol 7 ◽

Cited By ~ 28

Author(s):

Fabienne Lampert ◽

Diana Stafa ◽

Algera Goga ◽

Martin Varis Soste ◽

Samuel Gilberto ◽

...

Keyword(s):

Cell Cycle ◽

Cell Proliferation ◽

Ubiquitin Ligase ◽

E3 Ubiquitin Ligase ◽

Hierarchical Organization ◽

Negative Regulator ◽

Cell Cycle Exit ◽

Cellular Analysis ◽

Ubiquitin Ligase Activity

In yeast, the glucose-induced degradation-deficient (GID) E3 ligase selectively degrades superfluous gluconeogenic enzymes. Here, we identified all subunits of the mammalian GID/CTLH complex and provide a comprehensive map of its hierarchical organization and step-wise assembly. Biochemical reconstitution demonstrates that the mammalian complex possesses inherent E3 ubiquitin ligase activity, using Ube2H as its cognate E2. Deletions of multiple GID subunits compromise cell proliferation, and this defect is accompanied by deregulation of critical cell cycle markers such as the retinoblastoma (Rb) tumor suppressor, phospho-Histone H3 and Cyclin A. We identify the negative regulator of pro-proliferative genes Hbp1 as a bonafide GID/CTLH proteolytic substrate. Indeed, Hbp1 accumulates in cells lacking GID/CTLH activity, and Hbp1 physically interacts and is ubiquitinated in vitro by reconstituted GID/CTLH complexes. Our biochemical and cellular analysis thus demonstrates that the GID/CTLH complex prevents cell cycle exit in G1, at least in part by degrading Hbp1.

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Liganded ERα Stimulates the E3 Ubiquitin Ligase Activity of UBE3C to Facilitate Cell Proliferation

Molecular Endocrinology ◽

10.1210/me.2015-1125 ◽

2015 ◽

Vol 29 (11) ◽

pp. 1646-1657 ◽

Cited By ~ 5

Author(s):

Maiko Okada ◽

Fumiaki Ohtake ◽

Hiroyuki Nishikawa ◽

Wenwen Wu ◽

Yasushi Saeki ◽

...

Keyword(s):

Cell Proliferation ◽

Ubiquitin Ligase ◽

E3 Ubiquitin Ligase ◽

Cyclin B1 ◽

Dependent Manner ◽

Ubiquitin Ligase Activity ◽

Dependent Cell ◽

Estrogen Antagonist

Abstract Estrogen receptor (ER)α is a well-characterized ligand-dependent transcription factor. However, the global picture of its nongenomic functions remains to be illustrated. Here, we demonstrate a novel function of ERα during mitosis that facilitates estrogen-dependent cell proliferation. An E3 ubiquitin ligase, UBE3C, was identified in an ERα complex from estrogen-treated MCF-7 breast cancer cells arrested at mitosis. UBE3C interacts with ERα during mitosis in an estrogen-dependent manner. In vitro, estrogen dramatically stimulates the E3 activity of UBE3C in the presence of ERα. This effect was inhibited by the estrogen antagonist tamoxifen. Importantly, estrogen enhances the ubiquitination of cyclin B1 (CCNB1) and destabilizes CCNB1 during mitosis in a manner dependent on endogenous UBE3C. ERα, UBE3C, and CCNB1 colocalize in prophase nuclei and at metaphase spindles before CCNB1 is degraded in anaphase. Depletion of UBE3C attenuates estrogen-dependent cell proliferation without affecting the transactivation function of ERα. Collectively, these results demonstrate a novel ligand-dependent action of ERα that stimulates the activity of an E3 ligase. The mitotic role of estrogen may contribute to its effects on proliferation in addition to its roles in target gene expression.

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