Gene Expression-Related Changes in Morphologies of Organelles and Cellular Component Organization in Mucopolysaccharidoses

Mucopolysaccharidoses (MPS) are inherited metabolic diseases characterized by accumulation of incompletely degraded glycosaminoglycans (GAGs) in lysosomes. Although primary causes of these diseases are mutations in genes coding for enzymes involved in lysosomal GAG degradation, it was demonstrated that storage of these complex carbohydrates provokes a cascade of secondary and tertiary changes affecting cellular functions. Potentially, this might lead to appearance of cellular disorders which could not be corrected even if the primary cause of the disease is removed. In this work, we studied changes in cellular organelles in MPS fibroblasts relative to control cells. All 11 types and subtypes of MPS were included into this study to obtain a complex picture of changes in organelles in this group of diseases. Two experimental approaches were employed, transcriptomic analyses and electron microscopic assessment of morphology of organelles. We analyzed levels of transcripts of genes grouped into two terms included into the QuickGO database, ‘Cellular component organization’ (GO:0016043) and ‘Cellular anatomical entity’ (GO:0110165), to find that number of transcripts with significantly changed levels in MPS fibroblasts vs. controls ranged from 109 to 322 (depending on MPS type) in GO:0016043, and from 70 to 208 in GO:0110165. This dysregulation of expression of genes crucial for proper structures and functions of various organelles was accompanied by severe changes in morphologies of lysosomes, nuclei, mitochondria, Golgi apparatus, and endoplasmic reticulum. Interestingly, some observed changes occurred in all/most MPS types while others were specific to particular disease types/subtypes. We suggest that severe changes in organelles in MPS cells might arise from dysregulation of expression of a battery of genes involved in organelles’ structures and functions. Intriguingly, normalization of GAG levels by using recombinant human enzymes specific to different MPS types corrected morphologies of some, but not all, organelles, while it failed to improve regulation of expression of selected genes. These results might suggest reasons for inability of enzyme replacement therapy to correct all MPS symptoms, particularly if initiated at advanced stages of the disease.

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Sirtuins and their role as physiological modulators of metabolism

Postępy Higieny i Medycyny Doświadczalnej ◽

10.5604/01.3001.0014.5247 ◽

2020 ◽

Vol 74 ◽

pp. 489-497

Author(s):

Grażyna Sygitowicz ◽

Dariusz Sitkiewicz

Keyword(s):

Energy Homeostasis ◽

Metabolic Diseases ◽

Whole Body ◽

Acid Oxidation ◽

Special Role ◽

Cellular Functions ◽

Current State ◽

Expression Of Genes ◽

Wide Range ◽

Adp Ribosyltransferase

The sirtuins are a family of highly evolutionary conserved NAD+-dependent deacetylases (SIRT1, 2, 3, 5). Certain human sirtuins (SIRT4, 6) have, in addition, an ADP-ribosyltransferase activity. SIRT1 and SIRT2 are located in the nucleus and cytoplasm; SIRT3 exists predominantly in mitochondria, and SIRT6 is located in the nucleus. The mammalian sirtuins have emerged as key metabolic sensors that directly link environmental nutrient signals to metabolic homeostasis. SIRT1 is involved in the regulation of gluconeogenesis and fatty acid oxidation, as well as inhibiting lipogenesis and inflammation in the liver. In addition, they contribute to the mobilization of fat in white adipose tissue, sense nutrient availability in the hypothalamus; regulate insulin secretion in the pancreas; as well as modulating the expression of genes responsible for the activity of the circadian clock in metabolic tissues. Sirtuins are implicated in a variety of cellular functions ranging from gene silencing, through the control of the cell cycle, to energy homeostasis. Caloric restriction, supported by polyphenols, including resveratrol, which is the SIRT1 activator, plays a special role in maintaining energy homeostasis. On a whole body level, the wide range of cellular activities of the sirtuins suggests that they could constitute a therapeutic target to combat obesity and related metabolic diseases. In addition, this work presents the current state of knowledge in the field of sirtuin activity in relation to nutritional status and lifespan.

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DNA methyltransferase inhibitors modulate histone methylation: epigenetic crosstalk between H3K4me3 and DNA methylation during sperm differentiation

Zygote ◽

10.1017/s0967199420000684 ◽

2021 ◽

pp. 1-6

Author(s):

Liliana Burlibaşa ◽

Alina-Teodora Nicu ◽

Carmen Domnariu

Keyword(s):

Dna Methylation ◽

Histone Methylation ◽

Dna Methyltransferase ◽

Integrated Approach ◽

Regulatory Mechanisms ◽

Temporal Expression ◽

Dna Methyltransferase Inhibitors ◽

Expression Of Genes ◽

Species Survival ◽

Advanced Stages

Summary The process of cytodifferentiation in spermatogenesis is governed by a unique genetic and molecular programme. In this context, accurate ‘tuning’ of the regulatory mechanisms involved in germ cells differentiation is required, as any error could have dramatic consequences on species survival and maintenance. To study the processes that govern the spatial–temporal expression of genes, as well as analyse transmission of epigenetic information to descendants, an integrated approach of genetics, biochemistry and cytology data is necessary. As information in the literature on interplay between DNA methylation and histone H3 lysine 4 trimethylation (H3K4me3) in the advanced stages of murine spermatogenesis is still scarce, we investigated the effect of a DNA methyltransferase inhibitor, 5-aza-2′-deoxycytidine, at the cytological level using immunocytochemistry methodology. Our results revealed a particular distribution of H3K4me3 during sperm cell differentiation and highlighted an important role for regulation of DNA methylation in controlling histone methylation and chromatin remodelling during spermatogenesis.

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NtbHLH1, a JAF13-like bHLH, interacts with NtMYB6 to enhance proanthocyanidin accumulation in Chinese Narcissus

BMC Plant Biology ◽

10.1186/s12870-021-03050-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yuxin Fan ◽

Jiayu Peng ◽

Jiacheng Wu ◽

Ping Zhou ◽

Ruijie He ◽

...

Keyword(s):

Flavonoid Biosynthesis ◽

Transcriptional Level ◽

Flavonoid Pathway ◽

Regulation Of Expression ◽

Over Expression ◽

Expression Of Genes ◽

Genes Encoding ◽

Regulatory Complex ◽

Positive Regulators ◽

R2r3 Myb

Abstract Background Flavonoid biosynthesis in plants is primarily regulated at the transcriptional level by transcription factors modulating the expression of genes encoding enzymes in the flavonoid pathway. One of the most studied transcription factor complexes involved in this regulation consists of a MYB, bHLH and WD40. However, in Chinese Narcissus (Narcissus tazetta L. var. chinensis), a popular monocot bulb flower, the regulatory mechanism of flavonoid biosynthesis remains unclear. Results In this work, genes related to the regulatory complex, NtbHLH1 and a R2R3-MYB NtMYB6, were cloned from Chinese Narcissus. Phylogenetic analysis indicated that NtbHLH1 belongs to the JAF13 clade of bHLH IIIf subgroup, while NtMYB6 was highly homologous to positive regulators of proanthocyanidin biosynthesis. Both NtbHLH1 and NtMYB6 have highest expression levels in basal plates of Narcissus, where there is an accumulation of proanthocyanidin. Ectopic over expression of NtbHLH1 in tobacco resulted in an increase in anthocyanin accumulation in flowers, and an up-regulation of expression of the endogenous tobacco bHLH AN1 and flavonoid biosynthesis genes. In contrast, the expression level of LAR gene was significantly increased in NtMYB6-transgenic tobacco. Dual luciferase assays showed that co-infiltration of NtbHLH1 and NtMYB6 significantly activated the promoter of Chinese Narcissus DFR gene. Furthermore, a yeast two-hybrid assay confirmed that NtbHLH1 interacts with NtMYB6. Conclusions Our results suggest that NtbHLH1 may function as a regulatory partner by interacting directly with NtMYB6 to enhance proanthocyanidin accumulation in Chinese Narcissus.

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Unusual increase of Scd1 and Elovl6 expression in rat inguinal adipose tissue

Open Life Sciences ◽

10.2478/s11535-012-0007-6 ◽

2012 ◽

Vol 7 (2) ◽

pp. 192-200

Author(s):

Jacek Turyn ◽

Adriana Mika ◽

Piotr Stepnowski ◽

Julian Swierczynski

Keyword(s):

Adipose Tissue ◽

Food Restriction ◽

Metabolic Diseases ◽

Quantitative Polymerase Chain Reaction ◽

Mrna Levels ◽

Gene Expressions ◽

Tissue Mass ◽

Expression Of Genes ◽

Fat Deposits ◽

Rat Adipose Tissue

AbstractIt is generally accepted that the location of body fat deposits may play an important role in the risk of developing some endocrine and metabolic diseases. We have studied the effect of food restriction and food restriction/refeeding, often practiced by individuals trying to lose body weight, on the expression of genes which are associated with obesity and certain metabolic disorders in inguinal, epididymal, and perirenal rat white adipose tissues. Gene expression was analyzed by real time semi-quantitative polymerase chain reaction and by Western blot. We found that prolonged food restriction caused a significant decrease of body and adipose tissue mass as well as the increase of Scd1 and Elovl6 gene expressions in all main rat adipose tissue deposits. Food restriction/refeeding caused increases of: a) Scd1 and Elovl6 mRNA levels in adipose tissue, b) Scd1 protein level and c) desaturation index in adipose tissue. The increased expression of both genes was unusually high in inguinal adipose tissue. The results suggest that the increase of Scd1 and Elovl6 gene expressions in white adipose tissue by prolonged food restriction and prolonged food restriction/refeeding may contribute to accelerated fat recovery that often occurs in individuals after food restriction/refeeding.

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New insights into the structural basis of integrin activation

Blood ◽

10.1182/blood-2003-01-0334 ◽

2003 ◽

Vol 102 (4) ◽

pp. 1155-1159 ◽

Cited By ~ 133

Author(s):

Jian-Ping Xiong ◽

Thilo Stehle ◽

Simon L. Goodman ◽

M. Amin Arnaout

Keyword(s):

Conformational Changes ◽

Structural Changes ◽

Structural Basis ◽

Integrin Activation ◽

Cellular Functions ◽

Electron Microscopic ◽

The Past ◽

Intracellular Signals ◽

Bidirectional Signaling ◽

New Hypothesis

Abstract Integrins are cell adhesion receptors that communicate biochemical and mechanical signals in a bidirectional manner across the plasma membrane and thus influence most cellular functions. Intracellular signals switch integrins into a ligand-competent state as a result of elicited conformational changes in the integrin ectodomain. Binding of extracellular ligands induces, in turn, structural changes that convey distinct signals to the cell interior. The structural basis of this bidirectional signaling has been the focus of intensive study for the past 3 decades. In this perspective, we develop a new hypothesis for integrin activation based on recent crystallographic, electron microscopic, and biochemical studies.

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SsPEP1, an Effector with Essential Cellular Functions in Sugarcane Smut Fungus

Journal of Fungi ◽

10.3390/jof7110954 ◽

2021 ◽

Vol 7 (11) ◽

pp. 954

Author(s):

Shan Lu ◽

Yukun Wang ◽

Xiaorui Shen ◽

Feng Guo ◽

Chunling Zhou ◽

...

Keyword(s):

Potent Inhibitor ◽

Mapk Signaling ◽

Symptom Development ◽

Cellular Functions ◽

Sporisorium Scitamineum ◽

Expression Of Genes ◽

Allele Dosage ◽

Biotrophic Fungi ◽

Related Stress ◽

Important Disease

Biotrophic fungi have to infect their host to obtain nutrients and must establish an interaction with the host to complete their life cycle. In this process, effectors play important roles in manipulating the host’s immune system to avoid being attacked. Sporisorium scitamineum is the causative agent of sugarcane smut, the most important disease in sugarcane-producing regions worldwide. In this work, we functionally characterized the conserved effector PEP1 in S. scitamineum. The mating process and the expression of genes in the MAPK signaling pathway and the a and b loci were adversely affected in Sspep1-null mutants. The requirement for SsPEP1 in pathogenicity and symptom development was allele dosage-dependent, i.e., deleting one Sspep1 allele in the mating pair turned a normal black whip with abundant teliospores into a white whip with few teliospores; however, deleting both alleles almost abolished infectivity and whip development. ΔSspep1 mutants produced significantly less mycelium mass within infected plants. Additionally, SsPEP1 was identified as a potent inhibitor of sugarcane POD-1a peroxidase activity, implying that SsPEP1 may function to relieve reactive oxygen species-related stress within the host plant. Taken together, our work demonstrated that SsPEP1 is a multifaceted effector essential for S. scitamineum growth, development, and pathogenicity.

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Preconditioning by Hydrogen Peroxide Enhances Multiple Properties of HumanDecidua BasalisMesenchymal Stem/Multipotent Stromal Cells

Stem Cells International ◽

10.1155/2018/6480793 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13 ◽

Cited By ~ 8

Author(s):

T. Khatlani ◽

D. Algudiri ◽

R. Alenzi ◽

A. M. Al Subayyil ◽

F. M. Abomaray ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Stem Cell ◽

Cellular Functions ◽

Beneficial Effects ◽

Decidua Basalis ◽

Expression Of Genes ◽

Toxic Environment ◽

Stress Environment ◽

And Migration ◽

Hostile Environments

Stem cell-based therapies rely on stem cell ability to repair in an oxidative stress environment. Preconditioning of mesenchymal stem cells (MSCs) to a stress environment has beneficial effects on their ability to repair injured tissues. We previously reported that MSCs from thedecidua basalis(DBMSCs) of human placenta have many important cellular functions that make them potentially useful for cell-based therapies. Here, we studied the effect of DBMSC preconditioning to a stress environment. DBMSCs were exposed to various concentrations of hydrogen peroxide (H2O2), and their functions were then assessed. DBMSC expression of immune molecules after preconditioning was also determined. DBMSC preconditioning with H2O2enhanced their proliferation, colonogenicity, adhesion, and migration. In addition, DBMSCs regardless of H2O2treatment displayed antiangiogenic activity. H2O2preconditioning also increased DBMSC expression of genes that promote cellular functions and decreased the expression of genes, which have opposite effect on their functions. Preconditioning also reduced DBMSC expression of IL-1β, but had no effects on the expression of other immune molecules that promote proliferation, adhesion, and migration. These data show that DBMSCs resist a toxic environment, which adds to their potential as a candidate stem cell type for treating various diseases in hostile environments.

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Enzyme Replacement Therapy for Genetic Disorders Associated with Enzyme Deficiency

Current Medicinal Chemistry ◽

10.2174/0929867328666210526144654 ◽

2021 ◽

Vol 28 ◽

Author(s):

Marialaura Marchetti ◽

Serena Faggiano ◽

Andrea Mozzarelli

Keyword(s):

Enzyme Replacement Therapy ◽

Replacement Therapy ◽

Rare Diseases ◽

Mammalian Cells ◽

Metabolic Diseases ◽

Genetic Disorders ◽

Life Quality ◽

Lysosomal Storage Diseases ◽

Lysosomal Storage ◽

Enzyme Replacement

: Mutations in human genes might lead to loss of functional proteins, causing diseases. Among these genetic disorders, a large class is associated with the deficiency in metabolic enzymes, resulting in both an increase in the concentration of substrates and a loss in the metabolites produced by the catalyzed reactions. The identification of therapeutic actions based on small molecules represents a challenge to medicinal chemists because the target is missing. Alternative approaches are biology-based, ranging from gene and stem cell therapy, CRISPR/Cas9 technology, distinct types of RNAs, and enzyme replacement therapy (ERT). This review will focus on the latter approach that since the 1990s has been successfully applied to cure many rare diseases, most of them being lysosomal storage diseases or metabolic diseases. So far, a dozen enzymes have been approved by FDA/EMA for lysosome storage disorders and only a few for metabolic diseases. Enzymes for replacement therapy are mainly produced in mammalian cells and some in plant cells and yeasts and are further processed to obtain active, highly bioavailable, less degradable products. Issues still under investigation for the increase in ERT efficacy are the optimization of enzymes interaction with cell membrane and internalization, the reduction in immunogenicity, and the overcoming of blood-brain barrier limitations when neuronal cells need to be targeted. Overall, ERT has demonstrated its efficacy and safety in the treatment of many genetic rare diseases, both saving newborn lives and improving patients’ life quality, and represents a very successful example of targeted biologics.

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Myosin VI: cellular functions and motor properties

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2004.1563 ◽

2004 ◽

Vol 359 (1452) ◽

pp. 1931-1944 ◽

Cited By ~ 27

Author(s):

K. C. Holmes ◽

D. R. Trentham ◽

R. Simmons ◽

Rhys Roberts ◽

Ida Lister ◽

...

Keyword(s):

Optical Tweezers ◽

Leading Edge ◽

Force Transducer ◽

Myosin Vi ◽

Cellular Functions ◽

Electron Microscopic ◽

Coated Pits ◽

Microscopic Studies ◽

Golgi Network

Myosin VI has been localized in membrane ruffles at the leading edge of cells, at the trans–Golgi network compartment of the Golgi complex and in clathrin–coated pits or vesicles, indicating that it functions in a wide variety of intracellular processes. Myosin VI moves along actin filaments towards their minus end, which is the opposite direction to all of the other myosins so far studied (to our knowledge), and is therefore thought to have unique properties and functions. To investigate the cellular roles of myosin VI, we identified various myosin VI binding partners and are currently characterizing their interactions within the cell. As an alternative approach, we have expressed and purified full–length myosin VI and studied its in vitro properties. Previous studies assumed that myosin VI was a dimer, but our biochemical, biophysical and electron microscopic studies reveal that myosin VI can exist as a stable monomer. We observed, using an optical tweezers force transducer, that monomeric myosin VI is a non–processive motor which, despite a relatively short lever arm, generates a large working stroke of 18 nm. Whether monomer and/or dimer forms of myosin VI exist in cells and their possible functions will be discussed.

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Organic-acid transport in resealed haemoglobin-containing human erythrocyte ‘ghosts’

Biochemical Journal ◽

10.1042/bj1900653 ◽

1980 ◽

Vol 190 (3) ◽

pp. 653-658 ◽

Cited By ~ 17

Author(s):

A R Hubbard ◽

U Sprandel ◽

R A Chalmers

Keyword(s):

Organic Acids ◽

Metabolic Diseases ◽

Glyoxylic Acid ◽

Aliphatic Acid ◽

Erythrocyte Ghosts ◽

Cinnamic Acids ◽

Efflux Transport ◽

External Concentration ◽

Enzyme Replacement ◽

Organic Acid Transport

The transport of organic acids across the membrane of resealed haemoglobin-containing erythrocyte ‘ghosts’ prepared by a dialysis technique has been studied. The present work forms part of studies directed towards the use of erythrocyte cellular carriers in enzyme-replacement therapy of inherited metabolic diseases. Oxalic acid, glycollic acid and glyoxylic acid were taken as representative of aliphatic acids of low molecular mass and benzoic and cinnamic acids as representative of unsubstituted aromatic acids. These selected acids are important in the diseases with which the present work is concerned. Comparison of influx and efflux transport characteristics showed that erythrocyte ‘ghosts’ retain transport properties closely similar to those of normal erythrocytes. Rapid transport was observed with all organic acids studied and there was a linear relationship between initial amount of influx and external concentration of aliphatic acid. Saturation of the transport system was not observed up to 1 mM external concentration, and the presence of plasma in the external medium had no effect on transport characteristics. Transport in intact erythrocytes and prepared erythrocyte ‘ghosts’ from patients with hyperoxaluria was also studied.

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