Overexpression of DrosophilaNUAK or Constitutively‐Active Formin‐Like Promotes the Formation of Aberrant Myofibrils

Cytoskeleton, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 29, 2025

ABSTRACT Muscle development and maintenance is central to the normal functioning of animals. tissues exhibit high levels activity require dynamic turnover proteins. An actomyosin scaffold functions with additional proteins comprising basic contractile subunit striated muscle, known as sarcomere. Drosophila muscles are similar vertebrate in composition they share a mechanism development. NUAK (NUAK) homolog NUAK1 NUAK2 vertebrates. belongs family AMP‐activated protein kinases (AMPKs), group broad overlapping cellular targets. Here we confirm that dynamically modulates larval muscle sarcomere size upregulation produces longer sarcomeres, including increased thin filament lengths. Furthermore, overexpression results aberrant myofibers above nuclei plane, Formin‐like (Frl), an increase newly synthesized at sites consistent actin assembly. Expression constitutively‐active Frl also overexpression. These taken together strongly suggest functional link between myofibril formation vivo setting.

Language: Английский

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Titin-dependent biomechanical feedback tailors sarcomeres to specialized muscle functions in insects

Science Advances, Journal Year: 2025, Volume and Issue: 11(19)

Published: May 9, 2025

Sarcomeres are the universal contractile units of muscles that enable animals to move. Insect display a remarkable functional diversity: they operate at extremely different contraction frequencies (ranging from ~1 1000 hertz) and amplitudes during flying, walking, crawling. This is puzzling because sarcomeres built essentially same actin-myosin components. Here, we address how functionally made. We show giant protein titin regulation developmental contractility key for sarcomere specializations. I-band spans determines length sarcomeric in muscle type–specific manner. Unexpectedly, also rules force-generating myosin filament using feedback mechanism modulated by contractility. propose model specializations insects tuned, provide evidence this model, discuss its validity beyond insects.

Language: Английский

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DrosophilaTropomodulin is required for multiple actin-dependent processes within developing myofibers

Development, Journal Year: 2023, Volume and Issue: 150(6)

Published: Feb. 20, 2023

ABSTRACT Proper muscle contraction requires the assembly and maintenance of sarcomeres myofibrils. Although protein components myofibrils are generally known, less is known about mechanisms by which they individually function together synergize for myofibril maintenance. For example, it unclear how disruption actin filament (F-actin) regulatory proteins leads to weakness observed in myopathies. Here, we show that knockdown Drosophila Tropomodulin (Tmod), results several myopathy-related phenotypes, including reduction cell (myofiber) size, increased sarcomere length, disorganization misorientation myofibrils, ectopic F-actin accumulation, loss tension-mediating at myotendinous junction, misshaped internalized nuclei. Our findings support extend tension-driven self-organizing myofibrillogenesis model. We that, like its mammalian counterpart, Tmod caps pointed-ends, propose this activity crucial cellular processes different locations within myofiber directly indirectly contribute function. provide significant insights role development, disease.

Language: Английский

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Identification of CryAB as a target of NUAK kinase activity in Drosophila muscle tissue

Genetics, Journal Year: 2023, Volume and Issue: 225(3)

Published: Sept. 15, 2023

Phosphorylation reactions performed by protein kinases are one of the most studied post-translational modifications within cells. Much is understood about conserved residues kinase domains that perform catalysis phosphotransfer reaction, yet identity target substrates and downstream biological effects vary widely among cells, tissues, organisms. Here, we characterize key essential for NUAK activity in Drosophila melanogaster myogenesis homeostasis. Creation a kinase-dead mutation using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 results lethality at embryo to larval transition, while loss catalytic function later development produces aggregation chaperone αB-crystallin/CryAB muscle tissue. Yeast 2-hybrid assays demonstrate physical interaction between CryAB. We further show phospho-mimetic version promotes phosphorylation CryAB this modification occurs 2 previously unidentified phosphosites primary sequence human Mutation these serine D. abolishes phosphorylation, thus, proving their necessity biochemical level. These studies together highlight importance regulation provide platform explore tissue proteostasis.

Language: Английский

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UNC‐82/NUAK kinase is required by myosin A, but not myosin B, to assemble and function in the thick filament arms of C. elegans striated muscle

Cytoskeleton, Journal Year: 2023, Volume and Issue: 81(12), P. 753 - 774

Published: Nov. 20, 2023

Abstract The mechanisms that ensure proper assembly, activity, and turnover of myosin II filaments are fundamental to a diverse range cellular processes. In Caenorhabditis elegans striated muscle, thick contain two myosins functionally distinct spatially segregated. Using transgenic double mutants, we demonstrate the ability increased A expression restore muscle structure movement in B mutants requires UNC‐82/NUAK kinase activity. Myosin function appears unaffected kinase‐impaired unc‐82(e1220) mutant: recessive antimorphic effects on early assembly paramyosin this mutant counteracted by exacerbated loss B. chimeric motility assays, mapped region UNC‐82 activity 531‐amino‐acid coiled‐coil rod. This includes 264‐amino‐acid Region 1, which is sufficient rescue essential filament‐initiation A, as well sites interact with head domains Interacting Heads Motif. specific physical interaction between UNC‐82::GFP supported GFP labeling ectopic but not thin filaments. We hypothesize regulates competence during parallel filament arms.

Language: Английский

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Titin-dependent biomechanical feedback tailors sarcomeres to specialised muscle functions in insects

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 1, 2024

Abstract Sarcomeres are the contractile units of muscles that enable animals to move. Insect remarkable examples because they use extremely different contraction frequencies (ranging from ∼1 1000 Hz) and amplitudes for flying, walking crawling. This is puzzling sarcomeres built essentially same actin-myosin components. We show here giant protein titin key this functional specialisation. I-band spans determines length sarcomeric I-band, occurs in muscle-type-specific isoforms. Surprisingly, it also rules force-generating myosin filament a force feedback mechanism, even though not present there. provide evidence model its validity beyond insects. Summary Here we identified mechanical mechanism instructs fulfill specific needs muscle types.

Language: Английский

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Model Construction and Muscle Transcriptome Study of Zebrafish with Laminin-Alpha 2 Muscular Dystrophy

Indian Journal of Pharmaceutical Sciences, Journal Year: 2023, Volume and Issue: 85(S6)

Published: Jan. 1, 2023

The purpose of this study was to simulate muscular dystrophy disease by constructing a laminin-alpha 2 zebrafish model, and the changes muscle transcriptome using transcriptomic methods. Using clustered regularly interspaced short palindromic repeats associated protein 9 gene editing technology; knocked out or mutated. First, appropriate guide RNA sequence designed, then proteins were synthesized injected into embryos. lamininalpha model fish is screened identified detecting mutation DNA messenger in progeny genome. phenotype identification results 4 showed that phenotypes normal unable swimming individuals knockout group abnormal, while control not. characteristics confirmed. Functional enrichment pathway analysis differentially expressed genes performed further reveal biological processes regulatory pathways with fish. Transcriptome sequencing revealed difference expression between tissue wild-type zebrafish. These are involved such as development, metabolism signal transduction, providing important clues for understanding pathogenesis dystrophy. Through functional analysis, key signaling molecular mechanisms identified. findings provide theoretical basis discovery new therapeutic targets formulation corresponding strategies, ideas methods treatment diseases.

Language: Английский

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Gene expression profiling of NUAK kinase overexpression in Drosophila larval muscle development

Data in Brief, Journal Year: 2022, Volume and Issue: 43, P. 108482 - 108482

Published: July 22, 2022

Signal transduction pathways mediated by kinases control diverse biological outputs at the level of cells and tissues to regulate a array developmental events. To gain insight into how muscle expression evolutionarily conserved NUAK kinase regulates transcriptional landscape during Drosophila melanogaster development, we performed high-throughput sequencing RNA from either whole larvae or dissected fillets end larval development. Raw data was generated using Illumina HiSeq 4000 platform. After trimming mapping reference genome, differential gene GO enrichment analysis were completed. are deposited in NCBI Gene Expression Ominbus (GEO) repository under GEO accession GSE204894.

Language: Английский

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Drosophila Tropomodulin is required for multiple actin-dependent processes in myofiber assembly and maintenance

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2022, Volume and Issue: unknown

Published: Aug. 6, 2022

ABSTRACT Proper muscle contraction requires the assembly and maintenance of sarcomeres myofibrils. While protein components myofibrils are generally known, less is known about mechanisms by which they individually function together synergize for myofibril maintenance. For example, it unclear how disruption actin filament (F-actin) regulatory proteins leads to weakness observed in myopathies. Here, we show that knockdown Drosophila Tropomodulin (Tmod) results several myopathy-related phenotypes, including reduction cell (myofiber) size, increased sarcomere length, disorganization misorientation myofibrils, ectopic F-actin accumulation, loss tension-mediating at myotendinous junction, misshaped internalized nuclei. Our findings support extend tension-driven self-organization myofibrillogenesis model. We that, like its mammalian counterpart, Tmod caps pointed-ends, this activity critical cellular processes different locations within myofiber directly indirectly contribute function. provide significant insights role development, maintenance, disease. SUMMARY STATEMENT larval myofibers phenotypes. acts actin-related subcellular locales, all integrity

Language: Английский

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