a-colorimetric-assay-citrate-synthase-activity-drosophila

A Colorimetric Assay of Citrate Synthase Activity in <em>Drosophila Melanogaster</em>

Mitochondria play the most prominent roles in cellular metabolism by producing ATP through oxidative phosphorylation and regulating a variety of ...

crispr-based-modular-assembly-for-high-throughput-construction-uas

CRISPR-Based Modular Assembly for High-Throughput Construction of a UAS-cDNA/ORF Plasmid Library

Functional genomics screening offers a powerful approach to probe gene function and relies on the construction of genome-wide plasmid libraries. ...

embryo-microinjection-for-transgenesis-in-drosophila

Embryo Microinjection for Transgenesis in <em>Drosophila</em>

Transgenesis in Drosophila is an essential approach to studying gene function at the organism level. Embryo microinjection is a crucial step for the ...

crispr-based-shuttle-cloning-a-high-throughput-cloning-method

CRISPR-based Shuttle Cloning: A High-throughput Cloning Method

The development of genome-wide plasmid libraries using existing genomic repositories serves as a pivotal prerequisite for systematic functional ...

Shanghai Jiao Tong University School of Medicine

University of South China

The transcriptional co-activator PGC-1α is a key regulator of mitochondrial function and muscle fiber specification in the skeletal muscle. The E3 ubiquitin ligase RNF34 ubiquitinates PGC-1α and negatively regulates mammalian brown fat cell metabolism. However, the functional importance of RNF34 in the skeletal muscle and its impact on energy metabolism remain unknown. The Drosophila PGC-1 homolog dPGC-1 and its mammalian counterparts have conserved functions in mitochondria and insulin signaling. Here, we showed that the Drosophila RNF34 (dRNF34) ubiquitinates the Drosophila PGC-1α (dPGC-1) and promotes its degradation in HEK293T cells by immunoprecipitation and western blot analysis. This allows us to use Drosophila as a powerful model system to study the physiological role of RNF34 in mitochondrial function and metabolism. In the in vivo studies, by separately expressing two independent UAS-dRNF34 RNAi transgenes driven by the muscle-specific 24B-Gal4 driver, we found that knockdown of dRNF34 specifically in muscle promotes mitochondrial biogenesis, improves negative geotaxis, extends climbing time to exhaustion in moderate aged flies and counteracts high-fat-diet-induced high triglyceride content. Furthermore, we showed that knockdown of dPGC-1 reversed the effects of the dRNF34 knockdown phenotypes described above. Our results reveal that dRNF34 plays an important role in regulating mitochondrial biogenesis in muscle and lipid metabolism through dPGC-1. Thus, inhibition of RNF34 activity provides a potential novel therapeutic strategy for the treatment of age-related muscle dysfunction.

RNF34 modulates the mitochondrial biogenesis and exercise capacity in muscle and lipid metabolism through ubiquitination of PGC-1 in Drosophila.

Pathological TDP-43 aggregation is characteristic of several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD-TDP); however, how TDP-43 aggregation and function are regulated remain poorly understood. Here, we show that O-GlcNAc transferase OGT-mediated O-GlcNAcylation of TDP-43 suppresses ALS-associated proteinopathies and promotes TDP-43's splicing function. Biochemical and cell-based assays indicate that OGT's catalytic activity suppresses TDP-43 aggregation and hyperphosphorylation, whereas abolishment of TDP-43 O-GlcNAcylation impairs its RNA splicing activity. We further show that TDP-43 mutations in the O-GlcNAcylation sites improve locomotion defects of larvae and adult flies and extend adult life spans, following TDP-43 overexpression in Drosophila motor neurons. We finally demonstrate that O-GlcNAcylation of TDP-43 promotes proper splicing of many mRNAs, including STMN2, which is required for normal axonal outgrowth and regeneration. Our findings suggest that O-GlcNAcylation might be a target for the treatment of TDP-43-linked pathogenesis.

O-GlcNAcylation of TDP-43 suppresses proteinopathies and promotes TDP-43's mRNA splicing activity.

Stricture in patients with Crohn's disease (CD) carries a high risk of CD-related surgery in the course of the disease. The aim of this study was to assess the rate of occurrence of CD-related surgery and to determine baseline risk factors predicting subsequent surgery in this patient group.

Analysis of the risk of future gastrointestinal surgery in Crohn's disease with stricture.

The formation of the BCR-ABL fusion gene drives human chronic myeloid leukemia (CML). The last 2 decades have witnessed that specific tyrosine kinase inhibitors (TKIs, e.g., imatinib mesylate, IM) against ABL1 improve disease treatment, although some patients still suffer from relapse and TKI resistance. Therefore, a better understanding of the molecular pathology of CML is still urgently needed. miR-181a-5p (miR-181a) acts as a tumor suppressor in CML; however, the molecular mechanism of miR-181a in CML stem/progenitor cells remains elusive. Herein, we showed that miR-181a inhibited the growth of CML CD34 cells, including the quiescent subset, and sensitized them to IM treatment, while miR-181a inhibition by a sponge sequence collaborated with BCR-ABL to enhance the growth of normal CD34 cells. Transcriptome data and biochemical analysis revealed that SERPINE1 was a bona fide and critical target of miR-181a, which deepened the understanding of the regulatory mechanism of SERPINE1. Genetic and pharmacological inhibition of SERPINE1 led to apoptosis mainly mediated by caspase-9 activation. The dual inhibition of SERPINE1 and BCR-ABL exhibited a significantly stronger inhibitory effect than a single agent. Taken together, this study demonstrates that a novel miR-181a/SERPINE1 axis modulates CML stem/progenitor cells, which likely provides an important approach to override TKI resistance.

ArticleTotal : 4	Year
Publication title Cited by 1	2020
Publication title Cited by 1	2024
Publication title	2024
Publication title	2025

Article	Year
RNF34 modulates the mitochondrial biogenesis and exercise capacity in muscle and lipid metabolism through ubiquitination of PGC-1 in Drosophila. Acta biochimica et biophysica Sinica\| PubMed ID: 30247505	2018
O-GlcNAcylation of TDP-43 suppresses proteinopathies and promotes TDP-43's mRNA splicing activity. EMBO reports\| PubMed ID: 33855783	2021
Analysis of the risk of future gastrointestinal surgery in Crohn's disease with stricture. Saudi journal of gastroenterology : official journal of the Saudi Gastroenterology Association\| PubMed ID: 38011407	2024
miR-181a plays the tumor-suppressor role in chronic myeloid leukemia CD34 cells partially via SERPINE1. Cellular and molecular life sciences : CMLS\| PubMed ID: 38103082	2023
CRISPR-based shuttle cloning of 1,397 human genes into UAS vectors. Acta biochimica et biophysica Sinica\| PubMed ID: 40285452	2025

Wen Xue

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