scholarly journals Double Duty: Mitotic Kinesins and Their Post-Mitotic Functions in Neurons

Cells ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 136
Author(s):  
Nadine F. Joseph ◽  
Supriya Swarnkar ◽  
Sathyanarayanan V Puthanveettil
Keyword(s):  
Structural Changes ◽  
Motor Proteins ◽  
Molecular Motor ◽  
Critical Role ◽  
Cellular Materials ◽  
Microtubule Cytoskeleton ◽  
Axonal Arborization ◽  
Mitotic Cells

Neurons, regarded as post-mitotic cells, are characterized by their extensive dendritic and axonal arborization. This unique architecture imposes challenges to how to supply materials required at distal neuronal components. Kinesins are molecular motor proteins that mediate the active delivery of cellular materials along the microtubule cytoskeleton for facilitating the local biochemical and structural changes at the synapse. Recent studies have made intriguing observations that some kinesins that function during neuronal mitosis also have a critical role in post-mitotic neurons. However, we know very little about the function and regulation of such kinesins. Here, we summarize the known cellular and biochemical functions of mitotic kinesins in post-mitotic neurons.

An atomic resolution study of a carbide phase in platinum

1992 ◽  
Vol 50 (1) ◽  
pp. 20-21
Author(s):  
M.J. Witcomb ◽  
M.A. O'Keefe ◽  
CJ. Echer ◽  
C. Nelson ◽  
J.H. Turner ◽  
...  
Keyword(s):  
Solid Solution ◽  
Carbon Atom ◽  
Carbide Phase ◽  
Structural Changes ◽  
Critical Role ◽  
Alloy System ◽  
Atomic Resolution ◽  
Excess Carbon ◽  
Interstitial Carbon ◽  
Resolution Study

Under normal circumstances, Pt dissolves only a very small amount of interstitial carbon in solid solution. Even so, an appropriate quench/age treatment leads to the formation of stable Pt2C {100} plate precipitates. Excess (quenched-in) vacancies play a critical role in the process by accommodating the volume and structural changes that accompany the transformation. This alloy system exhibits other interesting properties. Due to a large vacancy/carbon atom binding energy, Pt can absorb excess carbon at high temperatures in a carburizing atmosphere. In regions rich in carbon and vacancies, another carbide phase, Pt7C which undergoes an order-disorder reaction was formed. The present study of Pt carburized at 1160°C and aged at 515°C shows that other carbides in the PtxC series can be produced.

scholarly journals PPARs as Metabolic Sensors and Therapeutic Targets in Liver Diseases

2021 ◽  
Vol 22 (15) ◽  
pp. 8298
Author(s):  
Hugo Christian Monroy-Ramirez ◽  
Marina Galicia-Moreno ◽  
Ana Sandoval-Rodriguez ◽  
Alejandra Meza-Rios ◽  
Arturo Santos ◽  
...  
Keyword(s):  
Liver Diseases ◽  
Metabolic Regulation ◽  
Structural Changes ◽  
Critical Role ◽  
The Body ◽  
Molecular Characteristics ◽  
Signal Pathways ◽  
Virus Infections ◽  
Physiological Processes ◽  
Hepatic Level

Carbohydrates and lipids are two components of the diet that provide the necessary energy to carry out various physiological processes to help maintain homeostasis in the body. However, when the metabolism of both biomolecules is altered, development of various liver diseases takes place; such as metabolic-associated fatty liver diseases (MAFLD), hepatitis B and C virus infections, alcoholic liver disease (ALD), and in more severe cases, hepatocelular carcinoma (HCC). On the other hand, PPARs are a family of ligand-dependent transcription factors with an important role in the regulation of metabolic processes to hepatic level as well as in other organs. After interaction with specific ligands, PPARs are translocated to the nucleus, undergoing structural changes to regulate gene transcription involved in lipid metabolism, adipogenesis, inflammation and metabolic homeostasis. This review aims to provide updated data about PPARs’ critical role in liver metabolic regulation, and their involvement triggering the genesis of several liver diseases. Information is provided about their molecular characteristics, cell signal pathways, and the main pharmacological therapies that modulate their function, currently engaged in the clinic scenario, or in pharmacological development.

scholarly journals Proprotein Convertase 5/6 Is Critical for Embryo Implantation in Women: Regulating Receptivity by Cleaving EBP50, Modulating Ezrin Binding, and Membrane-Cytoskeletal Interactions

Endocrinology ◽  
2011 ◽  
Vol 152 (12) ◽  
pp. 5041-5052 ◽  
Author(s):  
Sophea Heng ◽  
Ana Cervero ◽  
Carlos Simon ◽  
Andrew N. Stephens ◽  
Ying Li ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Cellular Localization ◽  
Structural Changes ◽  
Current Knowledge ◽  
Embryo Implantation ◽  
Critical Role ◽  
Human Endometrium ◽  
Scaffolding Protein ◽  
Proprotein Convertase ◽  
Proteomic Approach

Establishment of endometrial receptivity is vital for successful embryo implantation; its failure causes infertility. Epithelial receptivity acquisition involves dramatic structural changes in the plasma membrane and cytoskeleton. Proprotein convertase 5/6 (PC6), a serine protease of the proprotein convertase (PC) family, is up-regulated in the human endometrium specifically at the time of epithelial receptivity and stromal cell decidualization. PC6 is the only PC member tightly regulated in this manner. The current study addressed the importance and mechanisms of PC6 action in regulating receptivity in women. PC6 was dysregulated in the endometrial epithelium during the window of implantation in infertile women of three demographically different cohorts. Its critical role in receptivity was evidenced by a significant reduction in mouse blastocyst attachment of endometrial epithelial cells after PC6 knockdown by small interfering RNA. Using a proteomic approach, we discovered that PC6 cleaved the key scaffolding protein, ezrin-radixin-moesin binding phosphoprotein 50 (EBP50), thereby profoundly affecting its interaction with binding protein ezrin (a key protein bridging actin filaments and plasma membrane), EBP50/ezrin cellular localization, and cytoskeleton-membrane connections. We further validated this novel PC6 regulation of receptivity in human endometrium in vivo in fertile vs. infertile patients. These results strongly indicate that PC6 plays a key role in regulating fundamental cellular remodeling processes, such as plasma membrane transformation and membrane-cytoskeletal interface reorganization. PC6 cleavage of a crucial scaffolding protein EBP50, thereby profoundly regulating membrane-cytoskeletal reorganization, greatly extends the current knowledge of PC biology and provides substantial new mechanistic insight into the fields of reproduction, basic cellular biology, and PC biochemistry.

Remodeling of cardiac fiber structure after infarction in rats quantified with diffusion tensor MRI

2003 ◽  
Vol 285 (3) ◽  
pp. H946-H954 ◽  
Author(s):  
Junjie Chen ◽  
Sheng-Kwei Song ◽  
Wei Liu ◽  
Mark McLean ◽  
J. Stacy Allen ◽  
...  
Keyword(s):  
Structural Changes ◽  
Diffusion Tensor ◽  
Critical Role ◽  
Coronary Artery Occlusion ◽  
Tissue Level ◽  
Functional Adaptation ◽  
Angular Deviation ◽  
Diffusion Anisotropy ◽  
Structural Remodeling ◽  
Anisotropy Index

Structural remodeling of myocardium after infarction plays a critical role in functional adaptation. Diffusion tensor magnetic resonance imaging (DTMRI) provides a means for rapid and nondestructive characterization of the three-dimensional fiber architecture of cardiac tissues. In this study, microscopic structural changes caused by MI were evaluated in Fischer 344 rats 4 wk after infarct surgery. DTMRI studies were performed on 15 excised, formalin-fixed rat hearts of both infarct (left anterior descending coronary artery occlusion, n = 8) and control (sham, n = 7) rats. Infarct myocardium exhibited increased water diffusivity (41% increase in trace values) and decreased diffusion anisotropy (37% decrease in relative anisotropy index). The reduced diffusion anisotropy correlated negatively with microscopic fiber disarray determined by histological analysis ( R = 0.81). Transmural courses of fiber orientation angles in infarct zones were similar to those of normal myocardium. However, regional angular deviation of the diffusion tensor increased significantly in the infarct myocardium and correlated strongly with microscopic fiber disarray ( R = 0.86). These results suggest that DTMRI may provide a valuable tool for defining structural remodeling in diseased myocardium at the cellular and tissue level.

Persistent Pulmonary Hypertension of the Newborn: Role of Nitric Oxide

1995 ◽  
Vol 10 (6) ◽  
pp. 270-282
Author(s):  
Stella Kourembanas
Keyword(s):  
Nitric Oxide ◽  
Pulmonary Hypertension ◽  
Structural Changes ◽  
Critical Role ◽  
Persistent Pulmonary Hypertension ◽  
Cell Contractility ◽  
Vasoactive Mediators ◽  
Nitric Oxide Therapy

Persistent pulmonary hypertension of the newborn (PPHN) is a common cause of respiratory failure in the full-term neonate. Molecular and cellular studies in vascular biology have revealed that endothelial-derived mediators play a critical role in the pathogenesis and treatment of PPHN. Endothelial-derived vasoconstrictors, like endothelin, may increase smooth muscle cell contractility and growth, leading to the physiologic and structural changes observed in the pulmonary arterioles of infants with this disease. On the other hand, decreased production of the endothelial-derived relaxing factor, nitric oxide, may exacerbate pulmonary vasoreactivity and lead to more severe pulmonary hypertension. Exogenous (inhaled) nitric oxide therapy reduces pulmonary vascular resistance and improves oxygenation. The safety and efficacy of this therapy in reducing the need for extracorporeal membrane oxygenation and decreasing long-term morbidity is being tested in several trials nationally and abroad. Understanding the basic mechanisms that regulate the gene expression and production of these vasoactive mediators will lead to improved preventive and therapeutic strategies for PPHN.

Public Sector Role in Sustainable Development

2018 ◽  
pp. 149-159
Author(s):  
Onesmus Gichuru
Keyword(s):  
Public Sector ◽  
Structural Changes ◽  
Critical Role ◽  
Institutional Reforms ◽  
Unequal Distribution ◽  
The Public ◽  
Progressive Development ◽  
Social Structural ◽  
The Reformation ◽  
Attitudinal Changes

Being at a global development crossroad under an era plagued by major global challenges including financial crisis, poor governance, economic inequalities, climate change, food insecurity, human rights injustices, among others calls for a concerted effort from all the stakeholders to play a critical role in development. These roles are to be embraced through market-driven and people-centered modalities that seek to address inefficiency in service delivery and unequal distribution of economic gains. To foster this, the public sector is at the central point in driving institutional reforms in safeguarding progressive development-oriented norms and practices within an economy. In this regard, strategic reforms ought to be upheld as multifaceted processes that involve social structural changes, attitudinal changes, national institutions reforms, economic growth acceleration, reduction of inequalities, and poverty eradication. Restructuring, participation, public-private partnership, accountability, human-resource issues are some of the reformation strategies identified in this chapter.

scholarly journals Defining Bronchial Asthma with Phosphoinositide 3-Kinase Delta Activation: Towards Endotype-Driven Management

2019 ◽  
Vol 20 (14) ◽  
pp. 3525 ◽  
Author(s):  
Jae Seok Jeong ◽  
Jong Seung Kim ◽  
So Ri Kim ◽  
Yong Chul Lee
Keyword(s):  
Bronchial Asthma ◽  
Structural Changes ◽  
Critical Role ◽  
Asthma Management ◽  
Allergic Inflammation ◽  
Severe Form ◽  
Airway Epithelial ◽  
Positive Type ◽  
Effector Cells ◽  
Phosphoinositide 3 Kinase

Phosphoinositide 3-kinase (PI3K) pathways play a critical role in orchestrating the chronic inflammation and the structural changes of the airways in patients with asthma. Recently, a great deal of progress has been made in developing selective and effective PI3K-targeted therapies on the basis of a vast amount of studies on the roles of specific PI3K isoforms and fine-tuned modulators of PI3Ks in a particular disease context. In particular, the pivotal roles of delta isoform of class I PI3Ks (PI3K-δ) in CD4-positive type 2 helper T cells-dominant disorders such as asthma have been consistently reported since the early investigations. Furthermore, there has been great advancement in our knowledge of the implications of PI3K-δ in various facets of allergic inflammation. This has involved the airway epithelial interface, adaptive T and B cells, potent effector cells (eosinophils and neutrophils), and, more recently, subcellular organelles (endoplasmic reticulum and mitochondria) and cytoplasmic innate immune receptors such as NLRP3 inflammasome, all of which make this PI3K isoform an important druggable target for treating asthma. Defining subpopulations of asthma patients with PI3K-δ activation, namely PI3K-δ-driven asthma endotype, may therefore provide us with a novel framework for the treatment of the disease, particularly for corticosteroid-resistant severe form, an important unresolved aspect of the current asthma management. In this review, we specifically summarize the recent advancement of our knowledge on the critical roles of PI3K-δ in the pathogenesis of bronchial asthma.

scholarly journals A Metal Switch for Controlling the Activity of Molecular Motor Proteins

2013 ◽  
Vol 104 (2) ◽  
pp. 322a
Author(s):  
Jared C. Cochran ◽  
Yu C. Zhao ◽  
Dean E. Wilcox ◽  
F.J. Kull
Keyword(s):  
Motor Proteins ◽  
Molecular Motor
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