Androgen-receptor-interacting nuclear proteins

2000 ◽  
Vol 28 (4) ◽  
pp. 401-405 ◽  
Author(s):  
O. A. Jänne ◽  
A.-M. Moilanen ◽  
H. Poukka ◽  
N. Rouleau ◽  
U. Karvonen ◽  
...  

Androgen receptor (AR) belongs to the super-family of nuclear hormone receptors that employ complex molecular mechanisms to guide the development and physiological functions of their target tissues. Our recent work has led to the identification of four novel proteins that recognize AR zinc-finger region (ZFR) both in vivo and in vitro. One is a small nuclear RING-finger protein that possesses separate interaction interfaces for AR and for other transcription activators such as Spl. The second is a nuclear serine/threonine protein kinase (androgen-receptor-interacting nuclear protein kinase; ANPK); however, the receptor itself does not seem to be a substrate for this kinase. The third one is dubbed androgen-receptor-interacting protein 3 (ARIP3) and is a novel member of the PIAS (protein inhibitor of activated STAT) protein family. The fourth protein, termed ARIP4, is a nuclear ATPase that belongs to the SNF2-like family of chromatin remodelling proteins. All four proteins exhibit a punctate nuclear pattern when expressed in cultured cells. Each protein modulates AR-dependent transactivation in co-transfection experiments; their activating functions are not restricted to AR. Current work is aimed at elucidating the biochemical and functional properties of these AR-interacting proteins and at finding the partner proteins that form complexes with them in vivo.

2021 ◽  
Vol 12 ◽  
Author(s):  
Feixia Wang ◽  
Li Tang ◽  
Baoyu Liang ◽  
Chun Jin ◽  
Liyuan Gao ◽  
...  

Acute-on-chronic liver failure (ACLF) is described as a characteristic of acute jaundice and coagulation dysfunction. Effective treatments for ACLF are unavailable and hence are urgently required. We aimed to define the effect of Yi-Qi-Jian-Pi Formula (YQJPF) on liver injury and further examine the molecular mechanisms. In this study, we established CCl4-, LPS-, and d-galactosamine (D-Gal)-induced ACLF rat models in vivo and LPS- and D-Gal-induced hepatocyte injury models in vitro. We found that YQJPF significantly ameliorates liver injury in vivo and in vitro that is associated with the regulation of hepatocyte necroptosis. Specifically, YQJPF decreased expression of receptor-interacting protein kinase 1 (RIPK1), receptor-interacting protein kinase 3 (RIPK3) and pseudokinase mixed lineage kinase domain-like (MLKL) to inhibit the migration of RIPK1 and RIPK3 into necrosome. YQJPF also reduces the expression of inflammatory cytokines IL-6, IL-8, IL-1β, and TNF-α, which were regulated by RIPK3 mediates cell death. RIPK1 depletion was found to enhance the protective effect of YQJPF. Furthermore, we showed that YQJPF significantly downregulates the mitochondrial reactive oxygen species (ROS) production and mitochondrial depolarization, with ROS scavenger, 4-hydroxy-TEMPO treatment recovering impaired RIPK1-mediated necroptosis and reducing the expression of IL-6, IL-8, IL-1β, and TNF-α. In summary, our study revealed the molecular mechanism of protective effect of YQJPF on hepatocyte necroptosis, targeting RIPK1/RIPK3-complex-dependent necroptosis via ROS signaling. Overall, our results provided a novel perspective to indicate the positive role of YQJPF in ACLF.


IUCrJ ◽  
2018 ◽  
Vol 5 (6) ◽  
pp. 866-879 ◽  
Author(s):  
Woo-Chang Chung ◽  
Junsoo Kim ◽  
Byung Chul Kim ◽  
Hye-Ri Kang ◽  
JongHyeon Son ◽  
...  

Poly(ADP-ribose) polymerase 1 (PARP-1), an enzyme that modifies nuclear proteins by poly(ADP-ribosyl)ation, regulates various cellular activities and restricts the lytic replication of oncogenic gammaherpesviruses by inhibiting the function of replication and transcription activator (RTA), a key switch molecule of the viral life cycle. A viral PARP-1-interacting protein (vPIP) encoded by murine gammaherpesvirus 68 (MHV-68) orf49 facilitates lytic replication by disrupting interactions between PARP-1 and RTA. Here, the structure of MHV-68 vPIP was determined at 2.2 Å resolution. The structure consists of 12 α-helices with characteristic N-terminal β-strands (Nβ) and forms a V-shaped-twist dimer in the asymmetric unit. Structure-based mutagenesis revealed that Nβ and the α1 helix (residues 2–26) are essential for the nuclear localization and function of vPIP; three residues were then identified (Phe5, Ser12 and Thr16) that were critical for the function of vPIP and its interaction with PARP-1. A recombinant MHV-68 harboring mutations of these three residues showed severely attenuated viral replication both in vitro and in vivo. Moreover, ORF49 of Kaposi's sarcoma-associated herpesvirus also directly interacted with PARP-1, indicating a conserved mechanism of action of vPIPs. The results elucidate the novel molecular mechanisms by which oncogenic gammaherpesviruses overcome repression by PARP-1 using vPIPs.


2000 ◽  
Vol 151 (4) ◽  
pp. 763-778 ◽  
Author(s):  
Mark R. Frey ◽  
Jennifer A. Clark ◽  
Olga Leontieva ◽  
Joshua M. Uronis ◽  
Adrian R. Black ◽  
...  

Members of the protein kinase C (PKC) family of signal transduction molecules have been widely implicated in regulation of cell growth and differentiation, although the underlying molecular mechanisms involved remain poorly defined. Using combined in vitro and in vivo intestinal epithelial model systems, we demonstrate that PKC signaling can trigger a coordinated program of molecular events leading to cell cycle withdrawal into G0. PKC activation in the IEC-18 intestinal crypt cell line resulted in rapid downregulation of D-type cyclins and differential induction of p21waf1/cip1 and p27kip1, thus targeting all of the major G1/S cyclin-dependent kinase complexes. These events were associated with coordinated alterations in expression and phosphorylation of the pocket proteins p107, pRb, and p130 that drive cells to exit the cell cycle into G0 as indicated by concomitant downregulation of the DNA licensing factor cdc6. Manipulation of PKC isozyme levels in IEC-18 cells demonstrated that PKCα alone can trigger hallmark events of cell cycle withdrawal in intestinal epithelial cells. Notably, analysis of the developmental control of cell cycle regulatory molecules along the crypt–villus axis revealed that PKCα activation is appropriately positioned within intestinal crypts to trigger this program of cell cycle exit–specific events in situ. Together, these data point to PKCα as a key regulator of cell cycle withdrawal in the intestinal epithelium.


2019 ◽  
Vol 10 (11) ◽  
Author(s):  
Tamás Molnár ◽  
Anett Mázló ◽  
Vera Tslaf ◽  
Attila Gábor Szöllősi ◽  
Gabriella Emri ◽  
...  

Abstract Cell death has a fundamental impact on the evolution of degenerative disorders, autoimmune processes, inflammatory diseases, tumor formation and immune surveillance. Over the past couple of decades extensive studies have uncovered novel cell death pathways, which are independent of apoptosis. Among these is necroptosis, a tightly regulated, inflammatory form of cell death. Necroptosis contribute to the pathogenesis of many diseases and in this review, we will focus exclusively on necroptosis in humans. Necroptosis is considered a backup mechanism of apoptosis, but the in vivo appearance of necroptosis indicates that both caspase-mediated and caspase-independent mechanisms control necroptosis. Necroptosis is regulated on multiple levels, from the transcription, to the stability and posttranslational modifications of the necrosome components, to the availability of molecular interaction partners and the localization of receptor-interacting serine/threonine-protein kinase 1 (RIPK1), receptor-interacting serine/threonine-protein kinase 3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL). Accordingly, we classified the role of more than seventy molecules in necroptotic signaling based on consistent in vitro or in vivo evidence to understand the molecular background of necroptosis and to find opportunities where regulating the intensity and the modality of cell death could be exploited in clinical interventions. Necroptosis specific inhibitors are under development, but >20 drugs, already used in the treatment of various diseases, have the potential to regulate necroptosis. By listing necroptosis-modulated human diseases and cataloging the currently available drug-repertoire to modify necroptosis intensity, we hope to kick-start approaches with immediate translational potential. We also indicate where necroptosis regulating capacity should be considered in the current applications of these drugs.


2019 ◽  
Vol 20 (8) ◽  
pp. 1931
Author(s):  
Eva Louise Steinmetz ◽  
Denise Nicole Dewald ◽  
Nadine Luxem ◽  
Uwe Walldorf

The Drosophila homeodomain-interacting protein kinase (Hipk) is the fly representative of the well-conserved group of HIPKs in vertebrates. It was initially found through its characteristic interactions with homeodomain proteins. Hipk is involved in a variety of important developmental processes, such as the development of the eye or the nervous system. In the present study, we set Hipk and the Drosophila homeodomain proteins Homeobrain (Hbn), Empty spiracles (Ems), and Muscle segment homeobox (Msh) in an enzyme-substrate relationship. These homeoproteins are transcription factors that function during Drosophila neurogenesis and are, at least in part, conserved in vertebrates. We reveal a physical interaction between Hipk and the three homeodomain proteins in vivo using bimolecular fluorescence complementation (BiFC). In the course of in vitro phosphorylation analysis and subsequent mutational analysis we mapped several Hipk phosphorylation sites of Hbn, Ems, and Msh. The phosphorylation of Hbn, Ems, and Msh may provide further insight into the function of Hipk during development of the Drosophila nervous system.


2005 ◽  
Vol 389 (1) ◽  
pp. 127-135 ◽  
Author(s):  
Claire E. EYERS ◽  
Helen McNEILL ◽  
Axel KNEBEL ◽  
Nick MORRICE ◽  
Simon J. C. ARTHUR ◽  
...  

A protein expressed in immune cells and muscle was detected in muscle extracts as a substrate for several SAPKs (stress-activated protein kinases). It interacted specifically with the F-actin capping protein CapZ in splenocytes, and was therefore termed ‘CapZIP’ (CapZ-interacting protein). Human CapZIP was phosphorylated at Ser-179 and Ser-244 by MAPKAP-K2 (mitogen-activated protein kinase-activated protein kinase 2) or MAPKAP-K3 in vitro. Anisomycin induced the phosphorylation of CapZIP at Ser-179 in Jurkat cells, which was prevented by SB 203580, consistent with phosphorylation by MAPKAP-K2 and/or MAPKAP-K3. However, osmotic shock-induced phosphorylation of Ser-179 was unaffected by SB 203580. These and other results suggest that CapZIP is phosphorylated at Ser-179 in cells by MAPKAP-K2/MAPKAP-K3, and at least one other protein kinase. Stress-activated MAP kinase family members phosphorylated human CapZIP at many sites, including Ser-68, Ser-83, Ser-108 and Ser-216. Ser-108 became phosphorylated when Jurkat cells were exposed to osmotic shock, which was unaffected by SB 203580 and/or PD 184352, or in splenocytes from mice that do not express either SAPK3/p38γ or SAPK4/p38δ. Our results suggest that CapZIP may be phosphorylated by JNK (c-Jun N-terminal kinase), which phosphorylates CapZIP to >5 mol/mol within minutes in vitro. Osmotic shock or anisomycin triggered the dissociation of CapZIP from CapZ in Jurkat cells, suggesting that phosphorylation of CapZIP may regulate the ability of CapZ to remodel actin filament assembly in vivo.


2021 ◽  
Author(s):  
Liancheng Fan ◽  
Yiming Gong ◽  
Yuman He ◽  
Wei-Qiang Gao ◽  
Baijun Dong ◽  
...  

Abstract Background: The incidence of treatment-induced neuroendocrine prostate cancer (t-NEPC) has been greatly increasing after the usage of second-generation androgen receptor (AR) pathway inhibitors (ARPIs). Neuroendocrine differentiation (NED) is closely associated with ARPI treatment failure and poor prognosis in prostate cancer (PCa) patients. However, the molecular mechanisms of NED are not fully understood. Methods: TRIM59 expression was evaluated in PCa samples from patients at first diagnosis or at relapse stage post ARPI treatment by immunohistochemistry; in vitro effects of TRIM59 were determined by cell proliferation, sphere formation and cell migration assays; while in vivo analysis was performed using subcutaneous tumor model. Western blot, qPCR assay, dual luciferase assessment, chromatin immunoprecipitation and RNA sequencing were applied for mechanistic exploration.Results: Here we report that upregulation of TRIM59, a TRIM family protein, is strongly correlated with ARPI treatment mediated NED and shorter patient survival in PCas. AR binds to TRIM59 promoter and represses its transcription. ARPI treatment leads to a reversal of repressive epigenetic modifications on TRIM59 gene and the transcriptional restraint on TRIM59 by AR. Upregulated TRIM59 then drives the NED of PCa by enhancing the degradation of RB1 and P53 and upregulating downstream lineage plasticity-promoting transcription factor SOX2. Conclusion: Altogether, TRIM59 is negatively regulated by AR and acts as a key driver for NED in PCas. Our study provides a novel prognostic marker for PCas and shed new light on the molecular pathogenesis of t-NEPC, a deadly variant of PCa.


2021 ◽  
Vol 8 ◽  
Author(s):  
Jiexin Zhang ◽  
Weijing Feng ◽  
Minghui Li ◽  
Peier Chen ◽  
Xiaodong Ning ◽  
...  

Chronic cadmium (Cd) exposure contributes to the progression of cardiovascular disease (CVD), especially atherosclerosis (AS), but the underlying mechanism is unclear. Since mitochondrial homeostasis is emerging as a core player in the development of CVD, it might serve as a potential mechanism linking Cd exposure and AS. In this study, we aimed to investigate Cd-mediated AS through macrophage polarization and know the mechanisms of Cd-caused mitochondrial homeostasis imbalance. In vitro, flow cytometry shows that Cd exposure promotes M1-type polarization of macrophages, manifested as the increasing expressions of nuclear Factor kappa-light-chain-enhancer of activated B (NF-kB) and NLR family pyrin domain containing 3 (NLRP3). Mitochondrial homeostasis tests revealed that decreasing mitochondrial membrane potential and mitophage, increasing the mitochondrial superoxide (mROS), and mitochondrial fission are involved in the Cd-induced macrophage polarization. The upregulated expressions of receptor-interacting protein kinase 3 (RIPK3) and pseudokinase-mixed lineage kinase domain-like protein (p-MLKL) were observed. Knocking out RIPK3, followed by decreasing the expression of p-MLKL, improves the mitochondrial homeostasis imbalance which effectively reverses macrophage polarization. In vivo, the oil red O staining showed that Cd with higher blood significantly aggravates AS. Besides, M1-type polarization of macrophages and mitochondrial homeostasis imbalance were observed in the aortic roots of the mice through immunofluorescence and western blot. Knocking out RIPK3 restored the changes above. Finally, the administered N-acetyl cysteine (NAC) or mitochondrial division inhibitor-1 (Mdivi-1), which decreased the mROS or mitochondrial fission, inhibited the expressions of RIPK3 and p-MLKL, attenuating AS and macrophage M1-type polarization in the Cd-treated group. Consequently, the Cd exposure activated the RIPK3 pathway and impaired the mitochondrial homeostasis, resulting in pro-inflammatory macrophage polarization and subsequent AS. Knocking out RIPK3 provided a potential therapeutic target for Cd-caused macrophage polarization and subsequent AS.


2003 ◽  
Vol 23 (17) ◽  
pp. 6210-6220 ◽  
Author(s):  
Pei-Wen Hsiao ◽  
Christy J. Fryer ◽  
Kevin W. Trotter ◽  
Weidong Wang ◽  
Trevor K. Archer

ABSTRACT Nuclear hormone receptors are ligand-dependent transcriptional regulators that modulate chromatin structure. However, the precise molecular mechanisms by which receptors recruit chromatin-remodeling activity are not fully elucidated. We show that in the absence of its ligand-binding domain, the glucocorticoid receptor (GR) is able to interact with both nuclear receptor coactivators and the BRG1 chromatin-remodeling complex in vivo. Individually, the GR makes direct interactions with BRG1-associated factor 60a (BAF60a) and BAF57, but not with BRG1, BAF155, or BAF170. Further, BAF60a possesses at least two interaction surfaces, one for GR and BRG1 and a second for BAF155 and BAF170. A GR mutant, GR(R488Q), that fails to interact with BAF60a in vitro has reduced chromatin-remodeling activity and reduced transcriptional activity from the promoter assembled as chromatin in vivo. Stable expression of a BAF60a truncation mutant, BAF60a4-140, caused chromatin-specific loss of GR functions in vivo. In the presence of the BAF60a mutant, the GR fails to interact with the BRG1 complex and consequently is also deficient in its ability to activate transcription from chromatin. Thus, in addition to previously identified BAF250, BAF60a may provide another critical and direct link between nuclear receptors and the BRG1 complex that is required for promoter recruitment and subsequent chromatin remodeling.


2006 ◽  
Vol 393 (3) ◽  
pp. 789-795 ◽  
Author(s):  
Andrii Domanskyi ◽  
Katja T. Virtanen ◽  
Jorma J. Palvimo ◽  
Olli A. Jänne

ARIP4 [AR (androgen receptor)-interacting protein 4] is a member of the SNF2-like family of proteins. Its sequence similarity to known proteins is restricted to the centrally located SNF2 ATPase domain. ARIP4 is an active ATPase, and dsDNA (double-stranded DNA) and ssDNA (single-stranded DNA) enhance its catalytic activity. We show in the present study that ARIP4 interacts with AR and binds to DNA and mononucleosomes. The N-terminal region of ARIP4 mediates interaction with AR. Kinetic parameters of the ARIP4 ATPase are similar to those of BRG-1 and SNF2h, two members of the SNF2-like protein family, but the specific activity of ARIP4 protein purified to >90% homogeneity is approximately ten times lower, being 120 molecules of ATP hydrolysed by an ARIP4 molecule per min in contrast with approx. 1000 ATP molecules hydrolysed per min by ATP-dependent chromatin remodellers. Unlike other members of the SNF2 family, ARIP4 does not appear to form large protein complexes in vivo or remodel mononucleosomes in vitro. ARIP4 is covalently modified by sumoylation, and mutation of six potential SUMO (small ubiquitin-related modifier) attachment sites abolished the ability of ARIP4 to bind DNA, hydrolyse ATP and activate AR function. We conclude that, similar to its closest homologues in the SNF2-like protein family, ATRX (α-thalassemia, mental retardation, X-linked) and Rad54, ARIP4 does not seem to be a classical chromatin remodelling protein.


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