scholarly journals Keratin 19 interacts with GSK3β to regulate its nuclear accumulation and degradation of cyclin D3

2021 ◽  
Author(s):  
Pooja Sharma ◽  
Sarah Tiufekchiev ◽  
Victoria Lising ◽  
Seung Woo Chung ◽  
Jung Soo Suk ◽  
...  

Cyclin D3 regulates the G1/S transition and is frequently overexpressed in several cancer types including breast cancer, where it promotes tumor progression. Here, we show that a cytoskeletal protein keratin 19 (K19) physically interacts with a serine/threonine kinase GSK3β and prevents GSK3β-dependent degradation of cyclin D3. The absence of K19 allowed active GSK3β to accumulate in the nucleus and degrade cyclin D3. Specifically, the head domain of K19 was required to sustain inhibitory phosphorylation of GSK3β Ser9, prevent nuclear accumulation of GSK3β, and maintain cyclin D3 levels and cell proliferation. K19 was found to interact with GSK3β and K19-GSK3β interaction was mapped out to require Ser10 and Ser35 residues on the head domain of K19. Unlike wildtype K19, S10A and S35A mutants failed to maintain total and nuclear cyclin D3 levels and induce cell proliferation. Finally, we show that the K19-GSK3β-cyclin D3 pathway affected sensitivity of cells towards inhibitors to cyclin dependent kinase 4 and 6 (CDK4/6). Overall, these findings establish a role for K19 in the regulation of GSK3β-cyclin D3 pathway and demonstrate a potential strategy for overcoming resistance to CDK4/6 inhibitors.

2021 ◽  
Vol 32 (21) ◽  
Author(s):  
Pooja Sharma ◽  
Sarah Tiufekchiev ◽  
Victoria Lising ◽  
Seung Woo Chung ◽  
Jung Soo Suk ◽  
...  

Keratin 19 (K19) inhibits glycogen synthase kinase-3β (GSK3β) accumulation in the nucleus, preventing cyclin D3 degradation. K19 physically interacts with GSK3β, and this interaction requires Ser 10 and 35 of K19. Mutating either residues decreased cyclin D3 levels and cell proliferation. The K19–GSK3β–cyclin D3 pathway also regulates the sensitivity of cancer cells to CDK4/6 inhibitors.


2020 ◽  
Author(s):  
caixia An ◽  
hailong li ◽  
Rong Niu ◽  
xiaoguang liu ◽  
Yonghua Hu ◽  
...  

Abstract Background: Microtubule-associated serine/threonine kinase (MASTL) functions to regulate chromosome condensation and mitotic progression. Emerging reports showed that aberrant MASTL expression is commonly implicated in various human cancers and act as an oncogene. This study aimed to discover the potential significance of MASTL in gastric cancer, and to uncover relevant mechanisms. Methods: Lentivirus MASTL-shRNA was constructed and infected into MGC-803 cells to analysis its influences on cell proliferation by Green fluorescent protein (GFP)-based cellomics and colony formation assay, cell invasion and migration by transwell assay, apoptosis and cell cycle by flow cytometry detection, respectively. Nude mice and fluorescence imaging were used to characterize the regulation of tumor growth in vivo. Affymetrix mRNA microarray assay combined KEGG enrichment analysis were used to screen relevant molecules related to MASTL silencing. Finally,several aberrantly expressed genes were validated by quantitative reverse transcription PCR(RT-qPCR)and western blot detection. Results: Silencing MASTL significantly inhibited cell proliferation, migration and invasion, arrested cell cycle at G1 stage. Silencing MASTL reduced tumor growth in nude mice, and fluorescence imaging indicated that the total radiant efficiency of mice in the Lv-shMAST group was markedly reduced compared with in mice in the Lv-shCtrl group in vivo. Affymetrix mRNA microarray assay revealed that 124 genes upregulated, 167 genes downregulated. RT-qPCR and western blotting validation showed that cyclin dependent kinase 6(CDK6), bone morphogenetic protein 2(BMP2), snail family transcriptional repressor 2(SNAI2), phosphorylation-mechanistic target of rapamycin kinase (p-mTOR), phosphorylation-AKT serine/threonine kinase (p-AKT) and phosphorylation-p38 kinase (p-p38) are downregulated, and cyclin dependent kinase inhibitor 1A (CDKN1A) is upregulated. Conclusions: Silencing MASTL could significantly inhibit cell growth, migration ability, induce apoptosis, arrest cell cycle at G1 stage, and the mechanisms of which were mediated via inactivation of mTOR, AKT, p38 signal pathways.


2020 ◽  
Vol 21 (11) ◽  
pp. 4122 ◽  
Author(s):  
Miao Yu ◽  
Xiaoyan Shi ◽  
Mengmeng Ren ◽  
Lu Liu ◽  
Hao Qi ◽  
...  

Serine-threonine kinase receptor-associated protein (STRAP) functions as a regulator of both TGF-β and p53 signaling that participates in the regulation of cell proliferation and cell death in response to various stresses. Here, we demonstrate that STRAP acetylation plays an important role in p53-mediated cell cycle arrest and apoptosis. STRAP is acetylated at lysines 147, 148, and 156 by the acetyltransferases CREB-binding protein (CBP) and that the acetylation is reversed by the deacetylase sirtuin7 (SIRT7). Hypo- or hyperacetylation mutations of STRAP at lysines 147, 148, and 156 (3KR or 3KQ) influence its activation and stabilization of p53. Moreover, following 5-fluorouracil (5-FU) treatment, STRAP is mobilized from the cytoplasm to the nucleus and promotes STRAP acetylation. Our finding on the regulation of STRAP links p53 with SIRT7 influencing p53 activity and stability.


2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Ravi Manoharan ◽  
Hyun-A Seong ◽  
Hyunjung Ha

Serine-threonine kinase receptor-associated protein (STRAP) is a transforming growth factor β (TGF-β) receptor-interacting protein that has been implicated in both cell proliferation and cell death in response to various stresses. However, the precise roles of STRAP in these cellular processes are still unclear. The mechanisms by which STRAP controls both cell proliferation and cell death are now beginning to be unraveled. In addition to its biological roles, this review also focuses on the dual functions of STRAP in cancers displaying redox dysregulation, where it can behave as a tumor suppressor or an oncogene (i.e., it can either inhibit or promote tumor formation), depending on the cellular context. Further studies are needed to define the functions of STRAP and the redox-sensitive intracellular signaling pathways that enhance either cell proliferation or cell death in human cancer tissues, which may help in the development of effective treatments for cancer.


2021 ◽  
Vol 10 ◽  
Author(s):  
Yiwen Sang ◽  
Piaoping Kong ◽  
Shizhen Zhang ◽  
Lingyu Zhang ◽  
Ying Cao ◽  
...  

Serum and glucocorticoid-induced protein kinase 1 (SGK1) is a member of the “AGC” subfamily of protein kinases, which shares structural and functional similarities with the AKT family of kinases and displays serine/threonine kinase activity. Aberrant expression of SGK1 has profound cellular consequences and is closely correlated with human cancer. SGK1 is considered a canonical factor affecting the expression and signal transduction of multiple genes involved in the genesis and development of many human cancers. Abnormal expression of SGK1 has been found in tissue and may hopefully become a useful indicator of cancer progression. In addition, SGK1 acts as a prognostic factor for cancer patient survival. This review systematically summarizes and discusses the role of SGK1 as a diagnostic and prognostic biomarker of diverse cancer types; focuses on its essential roles and functions in tumorigenesis, cancer cell proliferation, apoptosis, invasion, metastasis, autophagy, metabolism, and therapy resistance and in the tumor microenvironment; and finally summarizes the current understanding of the regulatory mechanisms of SGK1 at the molecular level. Taken together, this evidence highlights the crucial role of SGK1 in tumorigenesis and cancer progression, revealing why it has emerged as a potential target for cancer therapy.


2019 ◽  
Vol 20 (4) ◽  
pp. 453-464 ◽  
Author(s):  
Shirin Eyvazi ◽  
Mohammad Saeid Hejazi ◽  
Homan Kahroba ◽  
Mozghan Abasi ◽  
Reza Eghdam Zamiri ◽  
...  

Cyclin Dependent Kinase 9 (CDK9) as a serine/threonine kinase belongs to a great number of CDKs. CDK9 is the main core of PTEF-b complex and phosphorylates RNA polymerase (RNAP) II besides other transcription factors which regulate gene transcription elongation in numerous physiological processes. Multi-functional nature of CDK9 in diverse cellular pathways proposes that it is as an appealing target. In this review, we summarized the recent findings on the molecular interaction of CDK9 with critical participant molecules to modulate their activity in various diseases. Furthermore, the presented review provides a rationale supporting the use of CDK9 as a therapeutic target in clinical developments for crucial diseases; particularly cancers will be reviewed.


Development ◽  
1997 ◽  
Vol 124 (16) ◽  
pp. 3167-3176 ◽  
Author(s):  
S.J. Newfeld ◽  
A. Mehra ◽  
M.A. Singer ◽  
J.L. Wrana ◽  
L. Attisano ◽  
...  

Mothers against dpp (Mad) is the prototype of a family of genes required for signaling by TGF-beta related ligands. In Drosophila, Mad is specifically required in cells responding to Decapentaplegic (DPP) signals. We further specify the role of Mad in DPP-mediated signaling by utilizing tkvQ199D, an activated form of the DPP type I receptor serine-threonine kinase thick veins (tkv). In the embryonic midgut, tkvQ199D mimics DPP-mediated inductive interactions. Homozygous Mad mutations block signaling by tkvQ199D. Appropriate responses to signaling by tkvQ199D are restored by expression of MAD protein in DPP-target cells. Endogenous MAD is phosphorylated in a ligand-dependent manner in Drosophila cell culture. DPP overexpression in the embryonic midgut induces MAD nuclear accumulation; after withdrawal of the overexpressed DPP signal, MAD is detected only in the cytoplasm. However, in three different tissues and developmental stages actively responding to endogenous DPP, MAD protein is detected in the cytoplasm but not in the nucleus. From these observations, we discuss possible roles for MAD in a DPP-dependent serine-threonine kinase signal transduction cascade integral to the proper interpretation of DPP signals.


2020 ◽  
Author(s):  
Wenlin Liao ◽  
Kun-Ze Lee ◽  
San-Hua Su ◽  
Yuju Luo

AbstractCyclin-dependent kinase-like 5 (CDKL5), an X-linked gene encoding a serine-threonine kinase, is enriched in the mammalian forebrain and critical for neuronal maturation and synaptic function. Mutations in this gene cause CDKL5 deficiency disorder (CDD) that is characterized by early-onset epileptic seizures, autistic behaviors and intellectual disability. Although numerous CDD symptoms have been recapitulated in mouse models, spontaneous seizures have not been reported in mice with CDKL5 deficiency. Here, we present the first systematic study of spontaneous seizures in a mouse model of CDD. Through wireless electroencephalographic (EEG) recording and simultaneous videotaping, we observed epileptiform discharges accompanied with ictal behaviors in pups lacking CDKL5 at a selective time window during the pre-weaning period. The seizure-like patterns of EEG showed robust increase in total number of spike events, the total number and duration of bursts in Cdkl5 null pups compared to wild-type littermate controls at the age of postnatal day 12 (P12). The mutants displayed not only jerky and spasm-like movements during the prolonged bursts of discharges at P12, but also strengthened ictal grasping in both juvenile stage and adulthood. In addition, loss of CDKL5 remarkably reduced the phosphorylation of K+/Cl- co-transporter 2, which may impede GABA-mediated inhibition, in the cortex of P12 mouse pups. Our study reveals previously unidentified phenotypes of early-onset seizures in CDKL5-deficient mice, highlights the translational value of mouse models of CDD and provides a potential molecular target for early diagnosis and treatment for CDD.Significance StatementCyclin-dependent kinase-like 5 (CDKL5) is an X-linked gene encoding a serine-threonine kinase. Mutations in this gene cause CDKL5 deficiency disorder (CDD), a rare disease characterized by developmental delays, autistic behaviors and early-onset epilepsy. Even though many symptoms of CDD patients have been phenocopied in mice, spontaneous seizures are yet to be reported in mouse models of CDD. Here, for the first time, we identified early-onset seizures and ictal behaviors in neonatal pups of CDKL5-deficient mice. Loss of CDKL5 also selectively reduced protein levels of phosphorylated K+/Cl-cotransporter 2 in neonatal cortex of mice. Our study reveals an indispensible role of CDKL5 in regulating neuronal excitability in developing brains and highlights the translational significance of the CDD mouse models.


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