Project description:The Chinese forest musk deer (FMD; Moschus berezovskii) is an endangered artiodactyl mammal. Musk secreted by the musk gland of male FMD has extremely high economic and medicinal value. At present, little is known about the development of musk glands and the molecular mechanism of musk secretion. In the present research, using snRNA-seq and snATAC-seq association analysis performed on musk glands of forest musk deer, coupled with several bioinformatics analyses, the dynamic transcriptional cell atlas of musk gland development was revealed and the genes and transcription factors affecting musk secretion were determined. Based on uniform manifold approximation and projection (UMAP) analysis, we identified 12 cell types from musk glands, including two different acinar cells (clusters 0 and 10). In addition, the expression of core target genes and core transcription factors was verified by fluorescence in situ hybridization and immunohistochemistry. Combined with weighted gene co-expression network analysis (WGCNA), we obtained a deeper biological understanding of the relationship between core transcription factors, differentially expressed genes and musk secretion related pathways. This study lays a foundation for improving musk yield and meeting market demand. In the meantime, it also contributes to reducing the hunting and poaching of wild forest musk deer, protecting forest musk deer resources and maintaining ecological balance.

2023-08-31 | GSE182087 | GEO

Expression data from untreated vs. BMP4-treated cultured wild-type and MuSK null muscle cells (myoblasts and myotubes)

Project description:Bone morphogenic proteins (BMPs) function in virtually all tissues with cell-type specific outcomes. Since there are a relatively small number of BMP receptors this exquisite signaling specificity requires additional molecules to regulate the output of this pathway. We demonstrated that the receptor tyrosine kinase MuSK that is selectively expressed in muscle and plays a critical role in synapse formation and maintenance binds to BMP4 and related BMPs. Since BMPs regulate the transcription of a set of genes, we performed microarrays for wild-type and MuSK null muscle cells to test if MuSK regulates BMP responses in muscle cells. We shought to determine if MuSK regulates BMP responses in muscle cells and if the cell context made any difference in MuSK regulation of BMP pathway. To test this, expression profiles of untreated vs. BMP4-treated undifferentiated myoblast and differentiated myotube cultures were generated for both wild-type and MuSK-null genotypes. All conditions were done in triplicates. In total 24 arrays were analyzed.

2015-08-03 | E-GEOD-59567 | biostudies-arrayexpress

Reemergence of pathogenic, autoantibody-producing B-cell clones in myasthenia gravis following B-cell depletion therapy.

Project description:Myasthenia gravis (MG) is an autoantibody-mediated autoimmune disorder of the neuromuscular junction. Some patients with MG have pathogenic mAbs that recognize muscle-specific tyrosine kinase (MuSK). Patients respond well to CD20-mediated B-cell depletion therapy (BCDT); most achieve complete stable remission. However, relapse often occurs. To further understand the immunomechanisms underlying relapse we sought to study autoantibody-producing B-cells over the course of BCDT. We developed a monomeric fluorescently labelled antigen to enrich for MuSK-specific B-cells, which was validated with a novel Nalm6 cell line engineered to express a human MuSK autoantibody as B-cell receptor. We found that MuSK-specific B-cells are rare within the circulation (<3 per 10 million cells). From two MuSK-specific B-cells isolated from two distinct patients, we generated human recombinant MuSK mAbs. The autoantibodies originated from plasmablasts, used the IgG4 subclass, recognized the Ig1-like domain of MuSK and showed pathogenic capacity using an in vitro AChR clustering assay. Persistent clones of the mAbs were identified through B-cell repertoire tracing. Clonal variants of 2E6 were detected at several timepoints spanning more than five years months and reemerged after BCDT-mediated remission, appearing several months prior to relapse. These results indicate that a reservoir of rare pathogenic MuSK autoantibody-expressing B cell clones survive BCDT, then reemerge prior to manifestation of clinical relapse. This study provides both a mechanistic understanding of MuSK MG relapse and a valuable candidate biomarker for relapse prediction.

2022-11-07 | GSE215237 | GEO

Transcriptome profiling of lung immune responses potentially related to acute respiratory distress syndrome in forest musk deer

Project description:ARDS-mediated lung transcriptome alterations were identified in forest musk deer. Moreover, multiple transcripts/genes involved in lung development and lung defense responses to bacteria/viruses/fungi in ARDS were filtered out in forest musk deer.

2022-10-19 | GSE191259 | GEO

The MuSK-BMP pathway maintains myofiber size in slow muscle through regulation of Akt-mTOR signaling

Project description:Myofiber size regulation is critical in health, disease, and aging. MuSK (muscle-specific kinase) is a BMP (bone morphogenetic protein) co-receptor that promotes and shapes BMP signaling that is expressed at all neuromuscular junctions and is also present extrasynaptically in the slow soleus muscle. To investigate the role of the MuSK-BMP pathway in vivo we generated mice lacking the BMP-binding MuSK Ig3 domain. These ∆Ig3-MuSK mice are viable and fertile with innervation levels comparable to wild type. In 3-month-old mice myofibers are smaller in the slow soleus, but not in the fast TA. Here we use bulk RNA-seq to perform transcriptomic analysis of slow and fast mouse muscle. RNAseq analysis revealed soleus-selective decreases in RNA metabolism and protein synthesis pathways as well as dysregulation of IGF1 pathway components. Moreover, Akt-mTOR signaling is reduced in soleus but not TA. We propose that the MuSK-BMP pathway acts extrasynaptically to maintain myofiber size in slow muscle by promoting protein synthetic pathways including the IGF1-Akt-mTOR signaling. These results reveal a novel mechanism for regulating myofiber size in slow muscle and introduce the MuSK-BMP pathway as a target for promoting muscle growth and combatting atrophy.

2024-01-10 | GSE212352 | GEO

Expression data from untreated vs. BMP4-treated cultured wild-type and MuSK null muscle cells (myoblasts and myotubes)

2015-08-03 | GSE59567 | GEO