Calpains — An elaborate proteolytic system

AbstractCalpain is an intracellular Ca2+-dependent cysteine protease (EC 3.4.22.17; Clan CA, family C02). Recent expansion of sequence data across the species definitively shows that calpain has been present throughout evolution; calpains are found in almost all eukaryotes and some bacteria, but not in archaebacteria. Fifteen genes within the human genome encode a calpain-like protease domain. Interestingly, some human calpains, particularly those with non-classical domain structures, are very similar to calpain homologs identified in evolutionarily distant organisms. Three-dimensional structural analyses have helped to identify calpain's unique mechanism of activation; the calpain protease domain comprises two core domains that fuse to form a functional protease only when bound to Ca2+ via well-conserved amino acids. This finding highlights the mechanistic characteristics shared by the numerous calpain homologs, despite the fact that they have divergent domain structures. In other words, calpains function through the same mechanism but are regulated independently. This article reviews the recent progress in calpain research, focusing on those studies that have helped to elucidate its mechanism of action. This article is part of a Special Issue entitled: Proteolysis 50years after the discovery of lysosome

Calpain chronicle—an enzyme family under multidisciplinary characterization

Calpain is an intracellular Ca2+-dependent cysteine protease (EC 3.4.22.17; Clan CA, family C02) discovered in 1964. It was also called CANP (Ca2+-activated neutral protease) as well as CASF, CDP, KAF, etc. until 1990. Calpains are found in almost all eukaryotes and a few bacteria, but not in archaebacteria. Calpains have a limited proteolytic activity, and function to transform or modulate their substrates’ structures and activities; they are therefore called, “modulator proteases.” In the human genome, 15 genes—CAPN1, CAPN2, etc.—encode a calpain-like protease domain. Their products are calpain homologs with divergent structures and various combinations of functional domains, including Ca2+-binding and microtubule-interaction domains. Genetic studies have linked calpain deficiencies to a variety of defects in many different organisms, including lethality, muscular dystrophies, gastropathy, and diabetes. This review of the study of calpains focuses especially on recent findings about their structure–function relationships. These discoveries have been greatly aided by the development of 3D structural studies and genetic models

Factors affecting the decision making to enter nursing course

The shortage of nurses is one of the very important social problems in Japan. This study by questionaire survey was done to reveal the factors affecting the decision making of senior highschool students to enter nursing course. Two handred thirty-four 3-year college students studying in nursing course their 168 parents and 109 highschool teachers responded, and those data were statistically analysed. The results were as follows; 1. Students' choice to the nursing course were done basically by themselves, but were influenced by their parents and highschool teachers. 2. They, highschool students, parents and teachers have little knowledge about nursing job and nursing education on that time. 3. The incease in number of bachelor course to nursing in Japan may have impact on students, their parents and teachers, and it may link with the increase of students aiming to be nurses

An eccentric calpain, CAPN3/p94/calpain-3

AbstractCalpains are Ca2+-regulated proteolytic enzymes that are involved in a variety of biological phenomena. Calpains process substrates by limited proteolysis to modulate various protein functions in the cell, and are thus called “modulator proteases.” CAPN3, previously called p94 or calpain-3, has unique features that are not found in any of the other 14 human calpains, or even in other proteases.For instance, CAPN3 undergoes extremely rapid and exhaustive autodegradation. CAPN3 is also the first (and so far, the only) intracellular enzyme found to depend on Na+ for its activation. CAPN3 has both proteolytic and non-proteolytic functions. It has the interesting distinction of being the only protease, other than a few virus proteases, with the ability to regain protease function after its autolytic dissociation; this occurs through a process known as intermolecular complementation (iMOC). Gene mutations causing CAPN3 defects are responsible for limb-girdle muscular dystrophy type 2A (LGMD2A).Unusual characteristics of CAPN3 have fascinated researchers, but have also hampered conventional biochemical analysis. In this review, we describe significant findings about CAPN3 from its discovery to the present, and suggest promising avenues for future CAPN3 research

キョウ ノ ショクモツ アレルギー タイオウ ト ガッコウ / エピペン トレーナー コウシュウ ニ ヨル キュウキュウ タイオウ ノ コウジョウ

近年、児童生徒のアレルギー疾患は増加しており、ほとんどの教員が教育活動の中で子どもの健康に配慮した対応を行っている。2012 年東京都のF 小学校では食物アレルギーの児童が、学校給食摂取後アナフィラキシーショックに陥り死亡する事故が発生したことから、学校では安全対策を行う努力が行われている。たいていの学校では、専門的な講習を受講した養護教諭が講師となり、救急法研修が行われ、実践的にエピペントレーナーを使った対応のシミュレーションが行われている。本研究ではその受講者の意識に注目した調査から、教員は実践場面の講習の理解が十分ではない結果が判明した。このことから、養護教諭が行うエピペントレーナー講習の効果的な方法として、事前に実践指導グループの講習を行い、指導者が各グループに入り誰もが様々な役割の対応ができるシミュレーションカリキュラムを用いたトレーニングが有効であることが考えられた。これらのことから、全ての学校は、学校安全計画に、1年間に1回以上シミュレーショントレーニング研修を位置づけ、養護教諭は専門職として常に研修の最前線の情報や技術を習得する努力が必要である。In late years, the allergic disease of the school children increase, and most of the teachers correspond them in considering for the health of the school children through the educational activities. In 2012 an accident occurred. A food allergy child of F Elementary School in Tokyo fell into anaphylactic shock and died after having the school meal. After that, through making effort to prevent from the accident,safety measures started against them. In most schools, Yogo teachers who had special training about Epipen performed the simulation training using Epipen-trainer practically in the first aid training. This study says that the understanding of the practice scene was not enough in the consciousness of teachers attended to the training. At this point, before the training, it is important to train some teachers as practice assistants, and to associate them with each participant groups in the class. The role playing with the practice assistant is based on the simulation curriculum and that will become more effective for the Epipen-trainer class introduced by Yogo teachers. Furthermore, to demand them in school safety plan, is that we have to have this simulation training more than once a year as same as another first aid training, and that Yogo teachers make effort to get new informations and skills as the experts of the first aid

ヨウゴ ジッセン ノ ジュウジツ ヲ ミチビク ホケンシツ ケイエイ / ジッタイ チョウサ ト ケイエイ ケンシュウカイ カラ ホケンシツ ケイエイ ヲ カンガエル

児童の養護をつかさどる事を職務とする養護教諭は、学校看護婦と称された時代から養護訓導を経て今日に至る。養護教諭と称して67 年、今日社会の変遷と共に子どもの健康問題は多様で複雑さを増し、その職務内容も一層専門性が求められている。養護教育の先人たちは、養護教諭養成が本格的に行われた時代から、職を説くに当たり保健室経営の視点をテキストに盛り込んでいる。現在の学校における養護活動はそれを基に培われてきており、「保健室経営」は決して目新しいものではない。しかしながら、養護実践は経営的には十分行われているとは言いがたく、実践のスキルを共有し、今後学校における保健室経営の水準を高める必要があるといえる。Yogo teachers, assuming the nursing of the school children, continue the function to the present day through the times called them the school nurses or the nursing teacher. During our history of 67 years as Yogo teachers, children have been experiencing diverse and complex health issues over time with the social changes. Now, our career requires a higher level of expertise. On preaching about the job, the ancestors of the nursing education incorporated the viewpoint of "the health room management" in the text, from the times when the school nurse training started on a full scale. The nursing activity in the current school has been cultivated on it, and "the health room management" is not a new concept. However, it may be said that the nursing practice is not carried out well. So it is necessary to share the skill of the practice and to raise the standard of "the health room management" in the school in future

Factors Affecting Home Care of Elders Report 1. Support Expected by the Elderly and Family

For the rapid increase of the elders in population in Japan after the 2nd world war, the arrangement of medical care for aged persons, both therapeutic and preventive, has become the serious social problem. To estimate the possibility of care at home and needs of elders and their family for public and volunteer services, questionnaire survey was carried out at Konko town in Okayama prefecture, Japan, in August 1990. More than half of the 105 elders older than 65 years and living alone (group A, 9 males and 96 females) replied to want to be cared for at home and 178 families with elders (group B) wanted to care for them at home. As for services they would wish to be offered when they would become bedridden at home, while group A wished to be visited and cared for by 'physician', 'home helper' and 'neighbor' in order of high rate group B 'physician', 'public health nurse' and 'nurse'. As for facility or assistance services, the former wanted 'purchasing, sweeping and washing', food delivery' and 'calling on' and the latter 'care consultation', 'assist of body bath' and 'economic aid'. Other supports or cares were also hopefully expected by both groups. The results shows that well-arrangement and promotion of a variety of constitional and personal support for home cares for elders in the community must be urged

Purkinje cells originate from cerebellar ventricular zone progenitors positive for Neph3 and E-cadherin

AbstractGABAergic Purkinje cells (PCs) provide the primary output from the cerebellar cortex, which controls movement and posture. Although the mechanisms of PC differentiation have been well studied, the precise origin and initial specification mechanism of PCs remain to be clarified. Here, we identified a cerebellar and spinal cord GABAergic progenitor-selective cell surface marker, Neph3, which is a direct downstream target gene of Ptf1a, an essential regulator of GABAergic neuron development. Using FACS, Neph3+ GABAergic progenitors were sorted from the embryonic cerebellum, and the cell fate of this population was mapped by culturing in vitro. We found that most of the Neph3+ populations sorted from the mouse E12.5 cerebellum were fated to differentiate into PCs while the remaining small fraction of Neph3+ cells were progenitors for Pax2+ interneurons, which are likely to be deep cerebellar nuclei GABAergic neurons. These results were confirmed by short-term in vivo lineage-tracing experiments using transgenic mice expressing Neph3 promoter-driven GFP. In addition, we identified E-cadherin as a marker selectively expressed by a dorsally localized subset of cerebellar Neph3+ cells. Sorting experiments revealed that the Neph3+ E-cadherinhigh population in the embryonic cerebellum defined PC progenitors while progenitors for Pax2+ interneurons were enriched in the Neph3+ E-cadherinlow population. Taken together, our results identify two spatially demarcated subregions that generate distinct cerebellar GABAergic subtypes and reveal the origin of PCs in the ventricular zone of the cerebellar primordium

Lack of collagen alpha 6(IV) chain in mice does not cause severe-to-profound hearing loss or cochlear malformation, a distinct phenotype from nonsyndromic hearing loss with COL4A6 missense mutation

Congenital hearing loss affects 1 in every 1000 births, with genetic mutations contributing to more than 50% of all cases. X-linked nonsyndromic hereditary hearing loss is associated with six loci (DFNX1-6) and five genes. Recently, the missense mutation (c.1771G>A, p.Gly591Ser) in COL4A6, encoding the basement membrane (BM) collagen alpha 6(IV) chain, was shown to be associated with X-linked congenital nonsyndromic hearing loss with cochlear malformation. However, the mechanism by which the COL4A6 mutation impacts hereditary hearing loss has not yet been elucidated. Herein, we investigated Col4a6 knockout (KO) effects on hearing function and cochlear formation in mice. Immunohistochemistry showed that the collagen alpha 6(IV) chain was distributed throughout the mouse cochlea within subepithelial BMs underlying the interdental cells, inner sulcus cells, basilar membrane, outer sulcus cells, root cells, Reissner's membrane, and perivascular BMs in the spiral limbus, spiral ligament, and stria vascularis. However, the click-evoked auditory brainstem response analysis did not show significant changes in the hearing threshold of Col4a6 KO mice compared with wild-type (WT) mice with the same genetic background. In addition, the cochlear structures of Col4a6 KO mice did not exhibit morphological alterations, according to the results of high-resolution micro-computed tomography and histology. Hence, loss of Col4a6 gene expression in mice showed normal click ABR thresholds and normal cochlear formation, which differs from humans with the COL4A6 missense mutation c.1771G>A, p.Gly591Ser. Therefore, the deleterious effects in the auditory system caused by the missense mutation in COL4A6 are likely due to the dominant-negative effects of the alpha 6(IV) chain and/or alpha 5 alpha 6 alpha 5(IV) heterotrimer with an aberrant structure that would not occur in cases with loss of gene expression

PLEIAD/SIMC1/C5orf25, a Novel Autolysis Regulator for a Skeletal-Muscle-Specific Calpain, CAPN3, Scaffolds a CAPN3 Substrate, CTBP1

AbstractCAPN3/p94/calpain-3 is a skeletal-muscle-specific member of the calpain protease family. Multiple muscle cell functions have been reported for CAPN3, and mutations in this protease cause limb-girdle muscular dystrophy type 2A. Little is known about the molecular mechanisms that allow CAPN3 to be so multifunctional. One hypothesis is that the very rapid and exhaustive autolytic activity of CAPN3 needs to be suppressed by dynamic molecular interactions for specific periods of time. The previously identified interaction between CAPN3 and connectin/titin, a giant molecule in muscle sarcomeres, supports this assumption; however, the regulatory mechanisms of non-sarcomere-associated CAPN3 are unknown. Here, we report that a novel CAPN3-binding protein, PLEIAD [Platform element for inhibition of autolytic degradation; originally called SIMC1/C5orf25 (SUMO-interacting motif containing protein 1/chromosome 5 open reading frame 25)], suppresses the protease activity of CAPN3. Database analyses showed that PLEIAD homologs, like CAPN3 homologs, are evolutionarily conserved in vertebrates. Furthermore, we found that PLEIAD also interacts with CTBP1 (C-terminal binding protein 1), a transcriptional co-regulator, and CTBP1 is proteolyzed in COS7 cells expressing CAPN3. The identified cleavage sites in CTBP1 suggested that it undergoes functional modification upon its proteolysis by CAPN3, as well as by conventional calpains. These results indicate that PLEIAD can shift its major function from CAPN3 suppression to CAPN3-substrate recruitment, depending on the cellular context. Taken together, our data suggest that PLEIAD is a novel regulatory scaffold for CAPN3, as reflected in its name