PP2A/B55α Substrate Recruitment As Defined By The Retinoblastoma-Related Protein p107

Protein phosphorylation is a reversible post-translation modification that is essential in cell signaling. It is estimated that a third of all cellular proteins are phosphorylated (reviewed in Ficarro et al., 2002), with more than 98% of those phosphorylation events occurring on serine and threonine residues (Olsen et al., 2006). Kinases are the necessary enzymes for phosphorylation and protein phosphatases dynamically reverse this action. While the mechanisms of substrate recognition for kinases have been well-characterized to date, the same is not true for phosphatases that play an equally important role in opposing kinase function and determining global phosphorylation levels in cells. This dichotomy has also translated into the clinic, where there has been a persistently narrow research focus on the development of small-molecule kinase inhibitors for use as chemotherapeutic agents, without an equal effort being placed into the generation of the analogous phosphatase activators (reviewed in Westermarck, 2018). Members of the phosphoprotein phosphatase (PPP) family of serine/threonine phosphatases are responsible for the majority of dephosphorylation in eukaryotic cells, with protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A) accounting for more than 90% of the total phosphatase activity (Moorhead et al., 2007; Virshup and Shenolikar, 2009). Structurally, PP2A is a trimeric holoenzyme consisting of a scaffold (A) subunit, a regulatory (B) subunit, and a catalytic (C) subunit. B55α is a ubiquitous regulatory subunit that is reported to target many substrates with critical functions in processes including cell division. A long-standing question that has persisted in the field of cellular signaling is as to how the most abundant serine/threonine PP2A holoenzyme, PP2A/B55α, specifically recognizes substrates and presents them to the enzyme active site for subsequent dephosphorylation. Such critical data have only recently become well understood for the B56 family of ‘B’ regulatory subunits, where an LxxIxE short linear motif (or SLiM) has been identified in a subset of protein targets and shown via crystal structure analysis to dock into a 100% conserved binding pocket on the B56 surface (Hertz et al., 2016; Wang et al., 2016a; Wang et al., 2016b; Wu et al., 2017). Here, we show how B55α recruits p107, a pRB-related tumor suppressor and B55α substrate. Using molecular and cellular approaches, we identified a conserved region 1 (R1, residues 615-626) encompassing the strongest p107 binding site. This enabled us to identify an “HxRVxxV619-625” SLiM in p107 as necessary for B55α binding and dephosphorylation of the proximal pSer-615 in vitro and in cells. Numerous additional PP2A/B55α substrates, including TAU, contain a related SLiM C-terminal from a proximal phosphosite, allowing us to propose a consensus SLiM sequence, “p[ST]-P-x(5-10)-[RK]-V-x-x-[VI]-R”. In support of this, mutation of conserved SLiM residues in TAU dramatically inhibits dephosphorylation by PP2A/B55α, validating its generality. Moreover, a data-guided computational model details the interaction of residues from the conserved p107 SLiM, the B55α groove, and phosphosite presentation to the PP2A/C active site. Altogether, these data provide key insights into PP2A/B55α mechanisms of substrate recruitment and active site engagement, and also facilitate identification and validation of new substrates, a key step towards understanding the role of PP2A/B55α in many key cellular processes. As a parallel continuation of our efforts to identify novel B55α substrates/regulators, we generated mutant B55α constructs that occlude PP2A/A-C dimer engagement but retain substrate binding to the β-propeller structure (allowing us to interrogate direct interactors). Our preliminary AP-MS data led to the identification of several proteins that bound better to our “monomeric B55α” mutant compared to wild-type B55α in the context of the PP2A/B55α heterotrimer, including the centrosomal proteins HAUS6 and CEP170 (two substrates previously validated in a phosphoproteomic screen by our lab), suggesting that these mutants trap substrates as they cannot be dephosphorylated by PP2A/C. These analyses also identified an enrichment of T-complex protein 1 subunits in the “monomeric B55α” mutant elutions, further supporting the notion that these mutants may function as dominant negatives. Several additional proteins of interest were identified in the two independent rounds of mass spectrometry, including subunits of the DNA-directed RNA polymerases I, II, and IV, as well as the double-strand break repair protein MRE11, which can be followed up as potential novel B55α substrates. These studies can contribute to significant advances in our understanding of the network of proteins that B55α interacts with, and thus the signaling pathways that can be modulated by PP2A/B55α complexes in cells. Moreover, these advances can also provide translational benefits as has been demonstrated through the study of PP2A activators termed SMAPs, which demonstrate selective stabilization of PP2A/B56α complexes in cells that result in selective dephosphorylation of substrates including the oncogenic target c-MYC.Biomedical Science

Living and Working Together in Organizations: Theme Relevance—An Introduction

Living together has always been a complex challenge. As a matter of fact, peo- ple interact, develop relationships, produce, and share spaces and time in organi- zations, with no chance to choose each other in the majority of cases. Different stories and professional gures intertwine highlighting that the Other cannot be reduced to the Self

〈講演記録 部局間協定締結５周年記念〉 中国的涉台学术研究 ―形势演变与范式转移

departmental bulletin pape

カインの旅-光を求めて-

Articledepartmental bulletin pape

The Challenges of Promoting Social Inclusion through Sport: The Experience of a Sport- Based Initiative in Italy

Social inclusion is broadly recognized as a priority to accomplish at an international level. While the influence of sport toward this social mission has been largely debated, literature lacks contributions capturing the challenges of sport when promoting social inclusion. Based in case study methodology, the investigation explores the impact of a multi-stakeholder sport initiative developing social inclusion for socially vulnerable youth and the related challenges of the intervention through in- depth interviews with diverse program stakeholders. The main findings indicated the emergence of four challenges: limited transferability of program outcomes for youth in living conditions of severe vulnerability; drop-out of youth in living conditions of severe vulnerability; limited sustainability of program social workers; lack of sports club management skills. The work highlights some limits of sport-based programs for social inclusion and discusses some implications for practice to maximize the societal impact of such interventions

A study on detecting abnormal movements of stroke patients

福井工業大学大学院工学研究科博士(工学)厚生労働省発表の「平成26年度患者調査の概況」1 )によると,脳血管疾患の総患者数(継続的な治療を受けていると推測される患者数)は,117万9,000人で非常に高い水準にある.また,そのうちの多くは上肢麻痺を伴い,上肢障害は日常生活に大幅な制限をもたらすため積極的なリハビリテーションは重要になる.平成27年度の国民医療費は42兆3,644億円で,そのうち脳血管疾患の医療費は,1兆7,821億円と増加しており2 ),今後も増え続けることが予測される.経済的で効率的なリハビリテーションを行なうことが必要とされる. 厚生労働省発表の「平成26年度患者調査の概況」1 )によると,脳血管疾患の総患者数(継続的な治療を受けていると推測される患者数)は,117万9,000人で非常に高い水準にある.また,そのうちの多くは上肢麻痺を伴い,上肢障害は日常生活に大幅な制限をもたらすため積極的なリハビリテーションは重要になる.平成27年度の国民医療費は42兆3,644億円で,そのうち脳血管疾患の医療費は,1兆7,821億円と増加しており2 ),今後も増え続けることが予測される.経済的で効率的なリハビリテーションを行なうことが必要とされる. しかし現在の脳卒中リハビリテーションにおける保健医療体制は,膨張する医療費を抑制することを狙い,漫然とリハビリを続けるのではなく,標準的な治療期間として標準的算定日数を発症日から180日としている.平成20年4月からは,治療を継続することにより,状態の改善が期待できると医学的に判断される場合には,標準的算定日数を超えても標準的算定日数内と同様の算定できるが,治療を継続された場合も1日6単位(2時間)までと制限があり回復に必要な集中的なリハビリテーションを行える状況にはない9).現在の保険診療体制では回復が見込めるにもかかわらず,対応できない事例が多く存在することが予想される.今後の課題としては,いかに集中的で,効率的なリハビリテーションを行うことが重要になる.そして退院後の施設や在宅において行われる維持期のリハビリテーションにおいても,集中的な訓練を行うことができる体制づくりが重要になる.このような状況にこたえるために近年,ロボット技術,バーチャルリアリティ(以下,VR)技術を応用した上肢リハビリテーション支援システム(以下,上肢リハ支援システム)が開発されている10-13).上肢リハビリテーション技術は,十分な安全性や信頼性が確保できれば,ロボット技術を用いて,訓練の自動化および半自動化を図り,治療訓練の補助として集中的な訓練を実現することが可能である.しかし現在,開発されている上肢リハビリテーション支援システムは非常に高価であり,前述した医療費増大の解決には結びつかない現状がある.脳卒中ガイドライン201514)では国内での実践事例は少ない状態と記載されている.これは経済的なものが最も大きな要因と考えられ,今後は安価なシステムの開発が求められる. また維持期などでセラピストのいない状況(在宅及び施設など)の自主的な訓練で,安全性,効率性の高いものにするには,上肢リハ支援システムが訓練中の対象者の状況把握を十分に行なえることが重要になる.多くの上肢リハ支援システムは,評価システムとしての側面も有しており15)16),脳卒中患者の訓練動作(リーチ動作)における異常性の検出や,重症度の判定,回復レベルの評価などが可能である.上肢機能に関する評価情報をデジタルデータ化することは,telerehabilitation17)18)など遠隔地においての対象者把握にも役立ち,在宅や施設等の様々なシーンの訓練を実現する.また脳卒中の運動障害に対するフィードバック訓練の効果は様々な研究で実証されており19-21),脳卒中患者の訓練動作中の異常性を評価できるシステムを組み込むことで,ロボット訓練におけるフィードバックが可能となり,訓練効果を向上させることにもつながる.しかし現在の上肢リハ支援システムによる測定は制限があり,特に比較的に安価な端点型End-effector Type)では,操作部である把持部の軌道などの測定でとどまる.把持型で手部以外の評価を行なうためには新たにモーションセンサを組み込むことが必要になる.またモーションセンサを用いれば上肢リハ支援システム以外のVR技術を用いた仮想上肢訓練や通常の作業療法で行なわれている机上訓練などの評価にも活用することができる。doctoral thesi

Developmental Items of Human Figure Drawing: Dance/Movement Therapy for Adults with Intellectual Disabilities

The purpose of this study was to identify and describe the characteristics of human figure drawing in adults with intellectual disabilities, and to evaluate the developmental items after a 3-month intervention program using dance/movement therapy. The program consisted of 26 sessions lasting 1-h each held twice weekly for 3 months. A group of 30 adults with intellectual disabilities participated. Before and after the program, the Koppitz human figure drawing test was applied to evaluate body knowledge through the developmental items, evaluating elements of the person’s cognitive developmental and maturity. After the intervention, results indicated improved body knowledge in the participants and a significant increase in the scores on the developmental items at the end of the program

Organisational Welfare in Italian SMEs: The Process of Valorising Human Resources

Organisational welfare is a complex private system that offers advantages to a company and its employees. However, when occupational welfare is largely implemented as an \u201ceconomic\u201d strategy, there is a high probability that it would not necessarily be capable of guaranteeing a profit. The risks and possibilities associated with the implementation of a welfare programme incur further challenges if applied to the context of SMEs. Thus, SMEs are organisational realities characterised by specific emotional and relational dynamics. As such, welfare in these realities takes on deep value and significance and so it potentially impacts processes of valorising human resources. With our study, we analysed welfare practices and representations within specific organisational realities (SMEs) in order to understand how welfare could impact organisational processes of valorising human resources. Based on our results, we realised that welfare can be seen as a sort of magnifying glass that allowed for the detection of the themes that led the organisations to reflect on their rooted values and identities. We suggest that SMEs should think about welfare as a process rather than a product, strengthening their awareness of factors, dynamics and processes that define the complexity of the quality of life in organisations

Signs of ‘Ndrangheta In Lombardy: Study of a Cultural Artifact

This work would like to be a contribution for a more thorough knowledge of the phenomenology of the Mafia in Lombardy. It is a study carried out according to an ethnographic approach, which proposes the analysis of a cultural artifact aiming at understanding the logics and structure of the Mafia organization from different social interlocutors’ representations and lived experiences

Near-Linear Time Dispersion of Mobile Agents

Consider that there are k ≤ n agents in a simple, connected, and undirected graph G = (V,E) with n nodes and m edges. The goal of the dispersion problem is to move these k agents to mutually distinct nodes. Agents can communicate only when they are at the same node, and no other communication means, such as whiteboards, are available. We assume that the agents operate synchronously. We consider two scenarios: when all agents are initially located at a single node (rooted setting) and when they are initially distributed over one or more nodes (general setting). Kshemkalyani and Sharma presented a dispersion algorithm for the general setting, which uses O(m_k) time and log(k + Δ) bits of memory per agent [OPODIS 2021], where m_k is the maximum number of edges in any induced subgraph of G with k nodes, and Δ is the maximum degree of G. This algorithm is currently the fastest in the literature, as no o(m_k)-time algorithm has been discovered, even for the rooted setting. In this paper, we present significantly faster algorithms for both the rooted and the general settings. First, we present an algorithm for the rooted setting that solves the dispersion problem in O(klog min(k,Δ)) = O(klog k) time using O(log (k+Δ)) bits of memory per agent. Next, we propose an algorithm for the general setting that achieves dispersion in O(k log k ⋅ log min(k,Δ)) = O(k log² k) time using O(log (k+Δ)) bits. Finally, for the rooted setting, we give a time-optimal (i.e., O(k)-time) algorithm with O(Δ+log k) bits of space per agent. All algorithms presented in this paper work only in the synchronous setting, while several algorithms in the literature, including the one given by Kshemkalyani and Sharma at OPODIS 2021, work in the asynchronous setting.journal articl