Effects of mutant lamins on nucleo-cytoskeletal coupling in Drosophila models of LMNA muscular dystrophy

Frontiers in Cell and Developmental Biology, Journal Year: 2022, Volume and Issue: 10

Published: Aug. 31, 2022

The nuclei of multinucleated skeletal muscles experience substantial external force during development and muscle contraction. Protection from such forces is partly provided by lamins, intermediate filaments that form a scaffold lining the inner nuclear membrane. Lamins play myriad roles, including maintenance shape stability, mediation mechanoresponses, nucleo-cytoskeletal coupling. Herein, we investigate how disease-causing mutant lamins alter myonuclear properties in response to mechanical force. This was accomplished

Language: Английский

---

Stage-specific modulation of Drosophila gene expression with muscle GAL4 promoters

Fly, Journal Year: 2025, Volume and Issue: 19(1)

Published: Jan. 7, 2025

The bipartite GAL4/UAS system is the most widely used method for targeted gene expression in Drosophila melanogaster and facilitates rapid vivo genetic experimentation. Defining precise patterns tissues and/or cell types under GAL4 control will continue to evolve suit experimental needs. However, spatial temporal some commonly muscle tissue promoters are still unclear. This missing information limits timing of experiments during development. Here, we focus on three muscle-enriched drivers (Mef2-GAL4, C57-GAL4 G7-GAL4) better inform selection appropriate promoter Specifically, G7-GAL4 turn first or second instar larval stages, respectively, can be bypass myogenesis studies function after

Language: Английский

---

LMNA R482L mutation causes impairments in C2C12 myoblasts subpopulations, alterations in metabolic reprogramming during differentiation, and oxidative stress

Scientific Reports, Journal Year: 2025, Volume and Issue: 15(1)

Published: Feb. 13, 2025

Abstract LMNA mutations causing classical familial partial lipodystrophy of Dunnigan type (FPLD2) usually affect residue R482. FPLD is a severe metabolic disorder that often leads to cardiovascular and skeletal muscle complications. How the functional properties muscles still not well understood. In present project, we investigated LMNA-R482L mutation-specific alterations in transgenic mouse C2C12 cell line myoblasts. Using single-cell RNA sequencing have studied transcriptional diversity cultured vitro cells. The mutation induces changes cluster composition increases expression genes related connective tissue development, oxidative stress, stress defense, autophagy population-specific manner. Bulk RNA-seq confirmed these results revealed dysregulation carbohydrate metabolism differentiated R482L myotubes was supported by ATP production profile evaluation. measurement reactive oxygen species (ROS) levels glutathione accumulation myoblasts indicates mutation-related mechanisms control ROS scavenging through antioxidant system. increased autophagy-related structures also shown. Overall, our experiments showed connection between redox status with pathological phenotypes cells bearing pathogenic mutation.

Language: Английский

---

Molecular mechanism on autophagy associated cardiovascular dysfunction in Drosophila melanogaster

Frontiers in Cell and Developmental Biology, Journal Year: 2025, Volume and Issue: 13

Published: March 3, 2025

As a highly conserved cellular process, autophagy has been the focus of extensive research due to its critical role in maintaining homeostasis and implications cardiovascular pathogenesis. The decline muscular function, along with neuronal system, increased sensitivity stress have recognized multiple animal models. Autophagic defects architecture dysfunction linked both physiological pathological conditions heart mammals Drosophila . In this review, we systematically analyze autophagy-associated pathways hearts fruit flies aim provide comprehensive understanding for developing potential treatments patients effective strategies agricultural applications. This analysis elucidates molecular mechanisms function under , offering significant insights into development diseases. loss key proteins, including transmembrane protein Atg9 partners Atg2 or Atg18, DmSestrin, leads cardiac hypertrophy structural abnormalities resembling age-dependent deterioration function. Members autophagy-related (Atg) gene family, nuclear skeletal lamins, mechanistic mammalian target rapamycin (mTOR) signaling are critically influential activation shown suppress laminopathy. mTORC1/C2 complexes, axis Atg2-AMPK/Sirt1/PGC-1α pathway, essential flies, governing development, growth, maturation, maintenance homeostasis. beneficial effects several interventions that enhance exercise cold stress, can influence autophagy-dependent TOR activity serine/threonine kinase Exercise increase when it is deficient inhibit excessive, highlighting dual health. review evaluates functional significance heart, particularly context relation mTORC-associated pathways. It contrasts underlying mammals. evolutionary conservation underscores value as model broader across species. study not only deepens our autophagy’s but also provides theoretical foundation application pest control.

Language: Английский

---

A genetic variant in SMAD7 acts as a modifier of LMNA -associated muscular dystrophy, implicating SMAD signaling as a therapeutic target

Science Advances, Journal Year: 2025, Volume and Issue: 11(16)

Published: April 18, 2025

Mutations in LMNA cause multiple types of muscular dystrophy ( -MD). The symptoms -MD are highly variable and sensitive to genetic background. To identify contributions this phenotypic variability, we performed whole-genome sequencing on four siblings possessing the same mutation with differing degrees skeletal muscle disease severity. We identified a variant SMAD7 that segregated severe disease. functionally test variant, generated Drosophila model orthologous fly genes. increased SMAD signaling enhanced defects caused by mutant lamin. Conversely, overexpression wild-type rescued function. These findings were extended humans showing is biopsy tissue from individuals compared age-matched controls. Collectively, our support as first tested modifier for suggest components pathway therapeutic targets.

Language: Английский

---

Oxidative Stress, Inflammation and Connexin Hemichannels in Muscular Dystrophies

Biomedicines, Journal Year: 2022, Volume and Issue: 10(2), P. 507 - 507

Published: Feb. 21, 2022

Muscular dystrophies (MDs) are a heterogeneous group of congenital neuromuscular disorders whose clinical signs include myalgia, skeletal muscle weakness, hypotonia, and atrophy that leads to progressive disability loss ambulation. MDs can also affect cardiac respiratory muscles, impairing life-expectancy. in clude Duchenne muscular dystrophy, Emery-Dreifuss facioscapulohumeral dystrophy limb-girdle dystrophy. These other caused by mutations genes encode proteins responsible for the structure function such as components dystrophin-glycoprotein-complex connect sarcomeric-actin with extracellular matrix, allowing contractile force transmission providing stability during contraction. Consequently, dystrophic conditions which affected, integrity is disrupted, leading local inflammatory responses, oxidative stress, Ca2+-dyshomeostasis degeneration. In this scenario, dysregulation connexin hemichannels seem be an early disruptor homeostasis further plays relevant role these processes. The interaction between all elements constitutes positive feedback loop contributes worsening diseases. Thus, we discuss here interplay inflammation, stress progression their potential therapeutic targets.

Language: Английский

---

The Influence of a Genetic Variant in CCDC78 on LMNA-Associated Skeletal Muscle Disease

International Journal of Molecular Sciences, Journal Year: 2024, Volume and Issue: 25(9), P. 4930 - 4930

Published: April 30, 2024

Mutations in the LMNA gene-encoding A-type lamins can cause Limb–Girdle muscular dystrophy Type 1B (LGMD1B). This disease presents with weakness and wasting of proximal skeletal muscles has a variable age onset severity. variability been attributed to genetic background differences among individuals; however, such variants have not well characterized. To identify variants, we investigated multigeneration family which affected individuals are diagnosed LGMD1B. The primary LGMD1B this is dominant mutation that activates cryptic splice site, leading five-nucleotide deletion mature mRNA. results frame shift premature stop translation. Skeletal muscle biopsies from members showed dystrophic features severity, fibers some possessing cores, regions sarcomeric disruption, paucity mitochondria, commonly associated Using whole genome sequencing (WGS), identified 21 DNA sequence segregate more profound cores. These include relatively common variant coiled-coil domain containing protein 78 (CCDC78). was given priority because another CCDC78 causes autosomal centronuclear myopathy-4, cores addition centrally positioned nuclei. Therefore, analyzed discovered those both contain accumulated RyR1. Muscle mislocalized RyR1 were absent less profoundly only mutation. Taken together, our findings suggest impart pathology combination accounts for phenotypes.

Language: Английский

---

The role of N-acetylcysteine in osteogenic microenvironment for bone tissue engineering

Frontiers in Cell and Developmental Biology, Journal Year: 2024, Volume and Issue: 12

Published: July 11, 2024

Bone defect is a common clinical symptom which can arise from various causes. Currently, bone tissue engineering has demonstrated positive therapeutic effects for repair by using seeding cells such as mesenchymal stem and precursor cells. N-acetylcysteine (NAC) stable, safe highly bioavailable antioxidant that shows promising prospects in due to the ability attenuate oxidative stress enhance osteogenic potential immune regulatory function of This review systematically introduces mechanism NAC, analyzes advancements NAC-related research involving cells, innate animal models, discusses its classic oral microenvironment an example, places particular emphasis on innovative applications NAC-modified biomaterials. Finally, current limitations future are proposed, with aim providing inspiration targeted readers field.

Language: Английский

---

Cystine-dependent antiporters buffer against excess intracellular reactive sulfur species-induced stress

Redox Biology, Journal Year: 2022, Volume and Issue: 57, P. 102514 - 102514

Published: Oct. 17, 2022

Reactive sulfur species (RSS) play a role in redox homeostasis; however, adaptive cell responses to excessive intracellular RSS are not well understood. Therefore, this study, we generated transgenic (Tg) mice overexpressing cystathionine gamma-lyase (CSE) produce RSS. Contrary expectations, tissue concentrations of RSS, such as cysteine persulfide (CysSSH), were comparable both wild-type and CSE Tg mice, but the plasma CysSSH significantly higher than mice. This export surplus was also observed primary hepatocytes Exposure generator sodium tetrasulfide (Na2S4) resulted an initial increase concentration which later returned basal levels after into extracellular space. Interestingly, among all amino acids, cystine (CysSSCys) found be essential for from mouse hepatocytes, HepG2 cells, HEK293 cells during Na2S4 exposure, suggesting that cystine/glutamate transporter (SLC7A11) contributes, at least partially, export. We established lines with knockout overexpression SLC7A11 used them confirm predominant antiporter CysSSCys CysSSH. poor efflux excess enhanced cellular stresses induced by polysulfidation proteins, mitochondrial damage, cytotoxicity. These results suggest presence response involves cystine-dependent maintain homeostasis.

Language: Английский

---

Global Proteomic Analysis Reveals Alterations in Differentially Expressed Proteins between Cardiopathic Lamin A/C Mutations

Journal of Proteome Research, Journal Year: 2024, Volume and Issue: 23(6), P. 1970 - 1982

Published: May 8, 2024

Lamin A/C (LMNA) is an important component of nuclear lamina. Mutations cause arrhythmia, heart failure, and sudden cardiac death. While LMNA-associated cardiomyopathy typically has aggressive course that responds poorly to conventional failure therapies, there variability in severity age penetrance between even within specific mutations, which understood at the cellular level. Further, this heterogeneity not previously been captured mimic heterozygous state, nor have hundreds clinical LMNA mutations represented. Herein, we overexpressed cardiopathic variants HEK cells utilized state-of-the-art quantitative proteomics compare global proteomic profiles (1) aggregating Q353 K alone, (2) coexpressed with WT, (3) N195 (4) nonaggregating E317 WT help capture some mutations. We analyzed each data set obtain differentially expressed proteins (DEPs) applied gene ontology (GO) KEGG pathway analyses. found a range 162 324 DEPs from over 6000 total protein IDs differences GO terms, pathways, function, further highlighting complexity laminopathies. Pathways disrupted by were validated redox, autophagy, apoptosis functional assays both 293 induced pluripotent stem cell derived cardiomyocytes (iPSC-CMs) for K. These expand our repertoire mutation-specific downstream effects may become useful as druggable targets personalized medicine approach

Language: Английский

---