作者: Ferreira, Marcos A ; Elkins, Jonathan M ; Teodoro, Bruno V M ; Cunha, Micael R ; Balourdas, Dimitrios-Ilias ; Urien, Bruno ; Gileadi, Carina ; Lemmens, Bennie B L G ; Massirer, Katlin B ; Vasconcelos, Stanley N S ; Dutra, Luiz A ; de Souza Gama, Fernando H ; Knapp, Stefan ; Couñago, Rafael M ; Azevedo, Hatylas ; Nilsson, Ann-Sofie ; Hawgood, Michael ; Ramos, Priscila Z ; Dos Reis, Caio Vinícius ; Serafim, Ricardo A M ; Gileadi, Opher ; Mueller, Susanne ; Almeida, Vitor M ; Mascarello, Alessandra ; Guimarães, Cristiano R W ; Takarada, Jéssica Emi ; Santiago, André S ; Salmazo, Anita

Vaccinia-related kinase 1 (VRK1) and the δ and ε isoforms of casein kinase 1 (CK1) are linked to various disease-relevant pathways. However, the lack of tool compounds for these kinases has significantly hampered our understanding of their cellular functions and therapeutic potential. Here, we describe the structure-based development of potent inhibitors of VRK1, a kinase highly expressed in various tumor types and crucial for cell proliferation and genome integrity. Kinome-wide profiling revealed that our compounds also inhibit CK1δ and CK1ε. We demonstrate that dihydropteridinones 35 and 36 mimic the cellular outcomes of VRK1 depletion. Complementary studies with existing CK1δ and CK1ε inhibitors suggest that these kinases may play overlapping roles in cell proliferation and genome instability. Together, our findings highlight the potential of VRK1 inhibition in treating p53-deficient tumors and possibly enhancing the efficacy of existing cancer therapies that target DNA stability or cell division.

2024-06-01·Neurobiology of Disease

CK1δ/ε kinases regulate TDP-43 phosphorylation and are therapeutic targets for ALS-related TDP-43 hyperphosphorylation

Article

作者: Ong, Kailee ; Yu, Haiyang ; Ko, Vivian I ; Ravits, John M ; Cleveland, Don W

Hyperphosphorylated TAR DNA-binding protein 43 (TDP-43) aggregates in the cytoplasm of neurons is the neuropathological hallmark of amyotrophic lateral sclerosis (ALS) and a group of neurodegenerative diseases collectively referred to as TDP-43 proteinopathies that includes frontotemporal dementia, Alzheimer's disease, and limbic onset age-related TDP-43 encephalopathy. The mechanism of TDP-43 phosphorylation is poorly understood. Previously we reported casein kinase 1 epsilon gene (CSNK1E gene encoding CK1ε protein) as being tightly correlated with phosphorylated TDP-43 (pTDP-43) pathology. Here we pursued studies to investigate in cellular models and in vitro how CK1ε and CK1δ (a closely related family sub-member) mediate TDP-43 phosphorylation in disease. We first validated the binding interaction between TDP-43 and either CK1δ and CK1ε using kinase activity assays and predictive bioinformatic database. We utilized novel inducible cellular models that generated translocated phosphorylated TDP-43 (pTDP-43) and cytoplasmic aggregation. Reducing CK1 kinase activity with siRNA or small molecule chemical inhibitors resulted in significant reduction of pTDP-43, in both soluble and insoluble protein fractions. We also established CK1δ and CK1ε are the primary kinases that phosphorylate TDP-43 compared to CK2α, CDC7, ERK1/2, p38α/MAPK14, and TTBK1, other identified kinases that have been implicated in TDP-43 phosphorylation. Throughout our studies, we were careful to examine both the soluble and insoluble TDP-43 protein fractions, the critical protein fractions related to protein aggregation diseases. These results identify CK1s as critical kinases involved in TDP-43 hyperphosphorylation and aggregation in cellular models and in vitro, and in turn are potential therapeutic targets by way of CK1δ/ε inhibitors.

2024-05-10·Science Advances

Substrate displacement of CK1 C-termini regulates kinase specificity

Article

作者: Johnson, Jared L ; Gould, Kathleen L ; Cantley, Lewis C ; Cullati, Sierra N ; Akizuki, Kazutoshi ; Chen, Jun-Song ; Yaron-Barir, Tomer M

CK1 kinases participate in many signaling pathways, and their regulation is of meaningful biological consequence. CK1s autophosphorylate their C-terminal noncatalytic tails, and eliminating these tails increases substrate phosphorylation in vitro, suggesting that the autophosphorylated C-termini act as inhibitory pseudosubstrates. To test this prediction, we comprehensively identified the autophosphorylation sites on Schizosaccharomyces pombe Hhp1 and human CK1ε. Phosphoablating mutations increased Hhp1 and CK1ε activity toward substrates. Peptides corresponding to the C-termini interacted with the kinase domains only when phosphorylated, and substrates competitively inhibited binding of the autophosphorylated tails to the substrate binding grooves. Tail autophosphorylation influenced the catalytic efficiency with which CK1s targeted different substrates, and truncating the tail of CK1δ broadened its linear peptide substrate motif, indicating that tails contribute to substrate specificity as well. Considering autophosphorylation of both T220 in the catalytic domain and C-terminal sites, we propose a displacement specificity model to describe how autophosphorylation modulates substrate specificity for the CK1 family.

项与 CK1δ x CK1ε 相关的新闻（医药）

2023-03-09

·药渡Daily

潜力新靶点系列1：CK1靶点药物研发盘点

1 前言蛋白激酶介导的蛋白质磷酸化是细胞中许多信号通路激活和失活的核心，因此，各种蛋白激酶的异常活性往往与许多疾病的发生和进展有关，特别是癌症。相应的，蛋白激酶是最具吸引力的药物抑制靶点之一，超过70种小分子激酶抑制剂已被批准用于临床[1]。在20世纪70年代初，体外酪蛋白磷酸化实验发现酪蛋白激酶1(casein kinase 1，CK1) 家族由不同的成员构成，随后CK1与不同信号分子构成的底物组合被大量发现。CK1家族广泛存在于不同的物种，从酵母到人的许多真核生物中都表达CK1家族成员且它们均具有高度保守性。哺乳动物CK1同种型 (α，β，γ，δ，ε) 及其剪接变体参与细胞不同的生理过程，包括膜运输、昼夜节律、细胞周期进程调控、染色体分离、细胞凋亡和细胞分化等，所有CK1成员的N端和C端非催化结构域显著不同，但是它们的激酶结构域具有高度的保守性。CK1在调控其他生命进程的同时其自身的活动和表达也受到严格调控，从而保证生命体各项活动有序进行。已知CK1调节的机制包括通过抑制性自磷酸化进行磷酸化和(或)被其他细胞蛋白激酶磷酸化，与细胞蛋白质或亚细胞隔离相互作用。CK1家族具有与多种底物结合的部位并且参与调节细胞生命过程，它在Wnt和Hedgehog(Hh)等信号调控、昼夜节律的调节、膜运输、细胞骨架维持、细胞分裂、DNA修复和核定位等过程中均扮演重要角色。CK1的识别基序可以在多种细胞中发现，基于细胞功能的多样性，如在免疫炎症反应和中心体相关的过程、DNA损伤相关的信号转导、昼夜节律调控中，CK1 以不同的形式调控不同的信号通路从而负责调节组织细胞的生长、增殖和凋亡等过程，因此如果CK1家族在信号通路中某一环节功能失调或障碍会导致机体病理过程的发生，如肿瘤形成或神经疾病等。图1 CK1中心体相关功能2 CK1信号通路在过去十年中出现的激酶中，酪蛋白激酶1 (CK1)已被认为是治疗包括癌症在内的多种疾病的有吸引力的靶点。个别CK1亚型显示出高度的结构同源性，这使得鉴定异构体选择性抑制剂具有挑战性，而它们涉及不同的生物过程。CK1激酶在几种细胞通信级联中起着关键作用，例如，CK1δ/ε成员在Wnt/β-catenin信号传导中起着激活作用，而CK1α则可以磷酸化β-catenin并触发其降解，充当Wnt信号通路抑制剂，另外也参与Hedgehog 及Hippo等信号通路的调控。在典型的Wnt/β-catenin信号通路中，所有CK1家族成员都参与其中。然而，这种参与是相当复杂的。在缺乏Wnt配体的情况下，CK1α与轴蛋白、腺瘤性大肠息肉病(APC)和β-catenin(Ser-45)相互作用并磷酸化，从而引发β-catenin被GSK3β进一步磷酸化并随后降解(图2A)。因此细胞质中的β-catenin含量很低，其下游的靶基因转录处于抑制状态。当Wnt配体存在时，GSK3β介导的β-catenin磷酸化被抑制，β-catenin最终不会被降解。该过程会受到CK1α，CK1γ，CK1ε和CK1δ的调节，最终导致β-catenin在细胞质中稳定存在，游离的β-catenin被转运入核，与TCF/LEF复合物等共激活因子相互作用,激活Wnt下游的靶基因转录。图2 CK1与Wnt信号通路[2]3 CK1抑制剂在研情况目前，进入临床的仅有Biotheryx Inc开发的BTX-A51及BTX-1188，且均为CK1α与其他靶点联合的药物，而CK1α也被认为是治疗急性髓系白血病(AML)的一个有吸引力的靶点。适应症方面，仅有辉瑞在开发精神疾病，其他药物均集中于肿瘤适应症的开发。全球首款PI3Kδ/CK1ε抑制剂Umbralisib（UKONIQ）是TG Therapeutics研发并于2021年2月获美国FDA批准上市，Umbralisib曾被美国FDA调查是否会增加患者死亡的风险，于2022年1月27日暂停了两项临床试验，随后被FDA撤回加速批准。4结语虽然CK1抑制剂作为药物靶标具有很大的潜力，但开发可用于体内的选择性CK1抑制剂仍然困难重重。创新药研发，每一关都是九死一生的冒险，即使成功获批上市，后续的临床应用如果出现安全性等问题，依然可能面临撤市的风险。参考文献[1] Attwood, M.M., Fabbro, D.,Sokolov, A.V. et al. Trends in kinase drug discovery: targets, indications andinhibitor design[J]. Nat Rev Drug Discov, 2021, 20, 839-861.[2] Knippschild U , Marc Krüger, Richter J , et al. The CK1 Family: Contribution to Cellular Stress Response and Its Role in Carcinogenesis[J]. Frontiers in Oncology, 2014, 4(4):96.医药咨询业务介绍药渡咨询依托其强大的药学数据库资源以及多学科背景的项目团成员，为国内外医药企业、投资机构、政府和园区提供产品线规划、立项、生产、销售项目尽调、价值评估和BD等各个环节定制化解决方案。1. 为国内外企业完成200多亿的融资和并购进行了CDD和项目价值评估2. 为全球TOP10的MNC中一半以上提供产品战略和BD机会服务3. 为国内外近20家VC或PE提供技术尽职调查服务4. 为国内50多家上市药企行业研究和具体项目转让评估服务5. 为多个园区的项目落地和执行提供可行性论证服务免责声明：“药渡Daily”公众号所转载文章来源于其他公众号平台，主要目的在于分享行业相关知识，传递当前最新资讯。图片、文章版权均属于原作者所有，如有侵权，请及时告知，我们会在24小时内删除相关信息。END👇关注药渡数据媒体矩阵

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