The structure and function of cardiac t-tubules in health and disease

The transverse tubules (t-tubules) are invaginations of the cell membrane rich in several ion channels and other proteins devoted to the critical task of excitation–contraction coupling in cardiac muscle cells (cardiomyocytes). They are thought to promote the synchronous activation of the whole depth of the cell despite the fact that the signal to contract is relayed across the external membrane. However, recent work has shown that t-tubule structure and function are complex and tightly regulated in healthy cardiomyocytes. In this review, we outline the rapidly accumulating knowledge of its novel roles and discuss the emerging evidence of t-tubule dysfunction in cardiac disease, especially heart failure. Controversy surrounds the t-tubules' regulatory elements, and we draw attention to work that is defining these elements from the genetic and the physiological levels. More generally, this field illustrates the challenges in the dissection of the complex relationship between cellular structure and function.

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Cardiac Transverse Tubules in Physiology and Heart Failure

Annual Review of Physiology ◽

10.1146/annurev-physiol-061121-040148 ◽

2021 ◽

Vol 84 (1) ◽

Author(s):

Katharine M. Dibb ◽

William E. Louch ◽

Andrew W. Trafford

Keyword(s):

Structure And Function ◽

Review Article ◽

Annual Review ◽

Publication Date ◽

Cell Interior ◽

Dynamic Regulation ◽

Contraction Coupling ◽

Health And Disease ◽

T Tubules ◽

And Function

In mammalian cardiac myocytes, the plasma membrane includes the surface sarcolemma but also a network of membrane invaginations called transverse (t-) tubules. These structures carry the action potential deep into the cell interior, allowing efficient triggering of Ca2+ release and initiation of contraction. Once thought to serve as rather static enablers of excitation-contraction coupling, recent work has provided a newfound appreciation of the plasticity of the t-tubule network's structure and function. Indeed, t-tubules are now understood to support dynamic regulation of the heartbeat across a range of timescales, during all stages of life, in both health and disease. This review article aims to summarize these concepts, with consideration given to emerging t-tubule regulators and their targeting in future therapies. Expected final online publication date for the Annual Review of Physiology, Volume 84 is February 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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Approaches and developments in studying the human microbiome network

Israel Journal of Ecology and Evolution ◽

10.1080/15659801.2015.1042768 ◽

2015 ◽

Vol 61 (2) ◽

pp. 90-94 ◽

Cited By ~ 1

Author(s):

Mor Nitzan ◽

Sefi Mintzer ◽

Hanah Margalit

Keyword(s):

Bacterial Population ◽

Bacterial Species ◽

Human Microbiome ◽

Structure And Function ◽

Complex Relationship ◽

Human Host ◽

Competition And Cooperation ◽

Health And Disease ◽

And Function

The human microbiome is dynamic and unique to each individual, and its role is being increasingly recognized in healthy physiology and in disease, including gastrointestinal and neuropsychiatric disorders. Therefore, characterizing the human microbiome and the factors that shape its bacterial population, how they are related to host-specific attributes, and understanding the ways in which it can be manipulated and the phenotypic consequences of such manipulations are of great importance. Characterization of the microbiome so far has been mostly based on compositional studies alone, where relative abundances of different species are compared in different conditions, such as health and disease. However, inter-relationships among the bacterial species, such as competition and cooperation over metabolic resources, may be an important factor that affects the structure and function of the microbiome. Here we review the network-based approaches in answering such questions and explore the first attempts that focus on the interactions facet, complementing compositional studies, towards understanding the microbiome structure and its complex relationship with the human host.

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The Laryngeal Epithelium in Reflux

Perspectives on Voice and Voice Disorders ◽

10.1044/vvd21.3.112 ◽

2011 ◽

Vol 21 (3) ◽

pp. 112-117 ◽

Cited By ~ 2

Author(s):

Elizabeth Erickson-Levendoski ◽

Mahalakshmi Sivasankar

Keyword(s):

Laryngopharyngeal Reflux ◽

Critical Role ◽

Structure And Function ◽

Laryngeal Disease ◽

Health And Disease ◽

And Function ◽

The Impact

The epithelium plays a critical role in the maintenance of laryngeal health. This is evident in that laryngeal disease may result when the integrity of the epithelium is compromised by insults such as laryngopharyngeal reflux. In this article, we will review the structure and function of the laryngeal epithelium and summarize the impact of laryngopharyngeal reflux on the epithelium. Research investigating the ramifications of reflux on the epithelium has improved our understanding of laryngeal disease associated with laryngopharyngeal reflux. It further highlights the need for continued research on the laryngeal epithelium in health and disease.

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Deubiquitylating enzymes in neuronal health and disease

Cell Death and Disease ◽

10.1038/s41419-020-03361-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Fatima Amer-Sarsour ◽

Alina Kordonsky ◽

Yevgeny Berdichevsky ◽

Gali Prag ◽

Avraham Ashkenazi

Keyword(s):

Human Brain ◽

Neurodegenerative Disorders ◽

Structure And Function ◽

Pivotal Role ◽

Protein Homeostasis ◽

Neuronal Function ◽

Health And Disease ◽

And Function

AbstractUbiquitylation and deubiquitylation play a pivotal role in protein homeostasis (proteostasis). Proteostasis shapes the proteome landscape in the human brain and its impairment is linked to neurodevelopmental and neurodegenerative disorders. Here we discuss the emerging roles of deubiquitylating enzymes in neuronal function and survival. We provide an updated perspective on the genetics, physiology, structure, and function of deubiquitylases in neuronal health and disease.

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