Photosynthesis and the role of plastids (kleptoplastids) in Sacoglossa (Heterobranchia, Gastropoda): a short review

2015 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Heike Wägele

Title (Bahasa Indonesia): Fotosintesis dan peran plastida [kleptoplastids] pada Sacoglossa [Heterobranchia, Gastropoda]: tinjauan singkat. In this manuscript I will give a short summary of our knowledge on photosyn-thesis in the enigmatic gastropod group Sacoglossa. Members of this group are able to sequester chloroplasts from their food algae (mainly Chlorophyta) and store them for weeks and months and it was assumed for a long time that they can use chloroplasts in a similar way as plants do. Only few sacoglossan species are able to perform photosynthesis for months, others are less effective or are not able at all. The processes involved are investigated now for a few years, but are still not clear. However we know now that many factors contribute to this enigmatic biological system. These include extrinsic (environment, origin and properties of the nutrition and the plastids) and intrinsic factors of slugs and algae (behaviour, physiological and anatomical properties). Plastids are not maintained by genes that might have originated by a horizontal gene transfer (HGT) from the algal genome into the slug genome, as was hypothesized for many years. We therefore have to focus our research now on other factors to understand what actually contributes to this unique metazoan phenomenon which is not yet understood. In this review, some of these new approaches are summarized. Dalam tulisan ini saya akan memberikan ringkasan singkat tentang fotosintesis pada gastropoda kelompok misterius Sacoglossa. Organisme anggota dari kelompok ini mampu menyerap kloroplas dari alga makanan mereka (terutama Chlorophyta) dan menyimpannya selama berminggu-minggu, bahkan berbulan-bulan, sehingga telah diasumsikan bahwa mereka dapat menggunakan kloroplas dengan cara yang sama seperti tanaman. Hanya sedikit spesies sacoglossan dapat melakukan fotosintesis selama berbulan-bulan, yang lain kurang efektif atau tidak mampu sama sekali. Proses yang terlibat diselidiki sekarang selama beberapa tahun, namun masih belum jelas. Namun kita tahu sekarang bahwa banyak faktor yang berkontribusi terhadap sistem biologis misterius ini. Ini termasuk ekstrinsik (lingkungan, asal dan sifat gizi dan plastida) dan faktor intrinsik siput dan ganggang (perilaku, fisiologis dan sifat anatomis). Plastida tidak dikelola oleh gen yang mungkin berasal oleh transfer gen horizontal (HGT) dari genom alga ke dalam genom slug, seperti yang dihipotesiskan selama bertahun-tahun. Oleh karena itu kita harus fokus penelitian kami sekarang pada faktor-faktor lain untuk memahami apa yang sebenarnya memberikan kontribusi terhadap fenomena ini metazoan unik yang belum dipahami. Dalam ulasan ini, beberapa pendekatan baru dirangkum.

2019 ◽  
Vol 47 (5) ◽  
pp. 1393-1404 ◽  
Author(s):  
Thomas Brand

Abstract The Popeye domain-containing gene family encodes a novel class of cAMP effector proteins in striated muscle tissue. In this short review, we first introduce the protein family and discuss their structure and function with an emphasis on their role in cyclic AMP signalling. Another focus of this review is the recently discovered role of POPDC genes as striated muscle disease genes, which have been associated with cardiac arrhythmia and muscular dystrophy. The pathological phenotypes observed in patients will be compared with phenotypes present in null and knockin mutations in zebrafish and mouse. A number of protein–protein interaction partners have been discovered and the potential role of POPDC proteins to control the subcellular localization and function of these interacting proteins will be discussed. Finally, we outline several areas, where research is urgently needed.


2008 ◽  
pp. 61-76
Author(s):  
A. Porshakov ◽  
A. Ponomarenko

The role of monetary factor in generating inflationary processes in Russia has stimulated various debates in social and scientific circles for a relatively long time. The authors show that identification of the specificity of relationship between money and inflation requires a complex approach based on statistical modeling and involving a wide range of indicators relevant for the price changes in the economy. As a result a model of inflation for Russia implying the decomposition of inflation dynamics into demand-side and supply-side factors is suggested. The main conclusion drawn is that during the recent years the volume of inflationary pressures in the Russian economy has been determined by the deviation of money supply from money demand, rather than by money supply alone. At the same time, monetary factor has a long-run spread over time impact on inflation.


INEOS OPEN ◽  
2020 ◽  
Vol 3 ◽  
Author(s):  
S. A. Sorokina ◽  
◽  
Yu. Yu. Stroilova ◽  
V. I. Muronets ◽  
Z. B. Shifrina ◽  
...  

Among the compounds able to efficiently inhibit the amyloid aggregation of proteins and decompose the amyloid aggregates that cause neurodegenerative diseases, of particular interest are dendrimers, which represent individual macromolecules with the hypercrosslinked architectures and given molecular parameters. This short review outlines the peculiarities of the antiamyloid activity of dendrimers and discusses the effect of dendrimer structures and external factors on their antiamyloid properties. The potential of application of dendrimers in further investigations on the aggregation processes of amyloid proteins as the compounds that exhibit the remarkable antiamyloid activity is evaluated.


2017 ◽  
Vol 5 (2) ◽  
pp. 171
Author(s):  
Yusnawarni Yusnawarni

To commemorate the 21st century, a new learning model was designed in 2013 curriculum, in which there is a shift from teachers give knowledge to students become student must actively seek out knowledge from a variety of learning resources. In this case, the teacher acts as facilitators. Thus, language is a very central role, because the language should be in front of all other subjects. Curriculum 2013 imposed a thematic integrated learning which is no longer based subjects. Various subjects for primary schools (such as: Religion, Civics, Indonesian, Mathematics, Science, Social Studies, and so on) are integrated intoone book. The subject matter is not presented in textbook, but it presented in book thematics lesson, the themes are about nature, social life and culture. In this new curriculum, learning process is implemented by applying a scientific approach (observing, questioning, experimenting, associating, and networking) that includes three aspects such as attitudes, knowledge, and skills. So, how is the role of Indonesian in an integrated thematic learning by applying scientific approaches in primary schools in 2013 curriculum? By appying the method, the object of this paper is to gain preview about the role of Indonesian in 2013 curriculum that uses integrated thematic learning by scientific approach in primary schools.AbstrakUntuk menyongsong abad ke-21, model pembelajaran baru dirancang dalam Kurikulum 2013, yang di dalamnya terdapat pergeseran dari siswa diberi tahu menjadi siswa harus aktif mencari tahu ilmu pengetahuan dari berbagai sumber belajar. Dalam hal ini, guru berperan sebagai fasilitator. Dengan demikian, peran bahasa menjadi sangat sentral, karena bahasa harus berada di depan semua mata pelajaran lain. Kurikulum 2013 memberlakukan pembelajaran tematik terpadu yang tidak lagi berbasis mata pelajaran. Berbagai mata pelajaran untuk sekolah dasar (seperti: Agama, PPKN, Bahasa Indonesia, Matematika, IPA, IPS, dan sebagainya) diintegrasi menjadi satu buku. Materi pelajaran tidak disajikan dalam buku mata pelajaran, tetapi dalam buku tema pelajaran, baik tema alam, sosial, maupun budaya. Proses pembelajaran dalam kurikulum baru ini diimplementasikan melalui pendekatan saintifik (mengamati, menanya, menalar, mencoba, dan mengomunikasikan) yang mencakup tiga aspek, yaitu sikap, pengetahuan, dan keterampilan. Lalu, bagaimana peran bahasa Indonesia dalam pembelajaran tematik terpadu melalui pendekatan saintifik di sekolah dasar pada Kurikulum 2013 ini? Melaluimetode deskriptif, yang menjadi tujuan penulisan ini adalah mendapatkan gambaran mengenai peran bahasa Indonesia dalam Kurikulum 2013 yang menggunakan pembelajaran tematik terpadu melalui pendekatan saintifik di sekolah dasar.


Author(s):  
М. В. Дзисюк

Definitions of concept and sphere of the concept are widely used in different aspects of modern linguistics. There is no single understanding of these notions and universal methodology of research has not been invented by linguists yet. This predetermines topicality of the article. The aim of our research is analysis, generalization, and systematization of different approaches to the interpretation of the notion ‘concept’ that exist in modern linguistics. It results in the following tasks: analysis of existing definitions of concept and its division into certain ranges and defining classification features. Modern linguists raise the questions of the conceptual and linguistic image of the world, the role of a human factor in its formation and interaction as in a linguistic process more frequently and it is defined as a fact in today’s linguistic scientific literature. The problem of individual language formation, poetic one in particular gains important meaning in this context. Ukrainian linguists use the notion of ‘concept’ for a long time now although they adhere to different views on its definition. Researches of the question define two major approaches in the analysis of the notion ‘concept’ that is linguistic-cognitive and linguistic-cultural. We can claim that words-concepts are agents between material reality and the ideal world that is synthesized in poetry, carriers of sense since with their help the versatility of the real world correlates with eternal spiritual values. Therefore, main features of the notion ‘concept’ in which objectively-cognitive and subjectively-creative features are combines are as follow sensual authenticity, time-spatial features, mediation between material and spiritual, semantic filling, ability to polysemy. A word with a generally symbolic meaning that is implemented in a language process through literary techniques typical for poet’s idiotype is the main core of the concept. The concept in poetic language formation by modern Uman poets is semantically integral, fulfilled, able to penetrate into other concepts and absorb semantically narrower images saving unity and semantic independence, varying numerous interpretations that project it in a certain semantic space, saving potential of real reflection.


2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Femmy Tresje Pelealu

This study is conducted in order to describe the development model ofconstructivistic teaching in Indonesian language for the sake of maximizing thestudents’ attitude in critical thinking. Operationally this study is done inorder to describe the concept and strategy model and the materials of constructivisticIndonesian language teaching developed by the teachers in SMP Negeri 1 Rembokenfor the sake of maximizing the students’ attitude in critical thinking. TheIndonesian language teachers’ concept on the planning and the conduction ofconstructivistic teaching related to what Indonesian language teaching is, howthe textbook and the materials are used, the purpose of Indonesian languageteaching is, the role of the teacher, the role of the students in the teachingand learning process, the use of teaching methods and media, and the procedureof the conduction of constructivistic Indonesian language teaching and learningprocess in the classroom, was not done by the teachers when they were observed.Their constructivistic teaching attitude is very minimal.


Author(s):  
Madara Eversone

The article aims to highlight the role of Arvīds Grigulis’ (1906–1989) personality in the Latvian Soviet literary process in the context of the Latvian Soviet Writers’ Union, attempting to discover the contradictions and significance of Arvīds Grigulis’ personality. Arvīds Grigulis was a long-time member of the Writers’ Union, a member of the Soviet nomenklatura, and an authority of the soviet literary process. His evaluations of pre-soviet literary heritage and writings of his contemporaries were often harsh and ruthless, and also influenced the development of the further literary process. The article is based on the documents of the Central Committee of the Latvian Communist Party, the Latvian Soviet Writers’ Union and the Communist Party local organization of the Latvian Soviet Writers’ Union that are available at the Latvian State Archive of the National Archives of Latvia, as well as memories of Grigulis’ contemporaries. It is concluded that the personality of the writer Arvīds Grigulis, although unfolding less in the context of the Writers’ Union, is essential for the exploration of the soviet literary process and events behind the scenes. The article mainly describes events and episodes taking place until 1965, when Arvīds Grigulis’ influence in the Writers’ Union was more remarkable. Individual and further studies should analyse changes and the impact of his decisions in the cultural process of the 70s and 80s of the 20th century.


Author(s):  
Stefan Gründer

Acid-sensing ion channels (ASICs) are proton-gated Na+ channels. Being almost ubiquitously present in neurons of the vertebrate nervous system, their precise function remained obscure for a long time. Various animal toxins that bind to ASICs with high affinity and specificity have been tremendously helpful in uncovering the role of ASICs. We now know that they contribute to synaptic transmission at excitatory synapses as well as to sensing metabolic acidosis and nociception. Moreover, detailed characterization of mouse models uncovered an unanticipated role of ASICs in disorders of the nervous system like stroke, multiple sclerosis, and pathological pain. This review provides an overview on the expression, structure, and pharmacology of ASICs plus a summary of what is known and what is still unknown about their physiological functions and their roles in diseases.


2021 ◽  
Vol 41 (01) ◽  
pp. 014-021
Author(s):  
Markus Bender ◽  
Raghavendra Palankar

AbstractPlatelet activation and aggregation are essential to limit blood loss at sites of vascular injury but may also lead to occlusion of diseased vessels. The platelet cytoskeleton is a critical component for proper hemostatic function. Platelets change their shape after activation and their contractile machinery mediates thrombus stabilization and clot retraction. In vitro studies have shown that platelets, which come into contact with proteins such as fibrinogen, spread and first form filopodia and then lamellipodia, the latter being plate-like protrusions with branched actin filaments. However, the role of platelet lamellipodia in hemostasis and thrombus formation has been unclear until recently. This short review will briefly summarize the recent findings on the contribution of the actin cytoskeleton and lamellipodial structures to platelet function.


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