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Biology subjects

Dey, B. K.

Publications and source records attributed to Dey, B. K..

6 recordsLinked to original sources

FTO promotes skeletal muscle differentiation and regeneration by regulating m6A-modified c-Myc

Recent studies have revealed the crucial role of m6A RNA methylation in various myogenic processes. However, the specific function and underlying molecular mechanisms of this modification in vivo during skeletal muscle differentiation and regeneration remain unclear. In this study, we examine the role and mechanism of the m6A RNA demethylase fat mass and obesity-associated protein (FTO) in skeletal muscle differentiation and regeneration in mice. Our findings demonstrate that FTO is upregulated during both skeletal muscle differentiation and regeneration and is essential for these key myogenic processes. We show that exogenous FTO expression in primary myoblasts enhances differentiation, whereas FTO knockdown inhibits it. Additionally, FTO knockout in mouse muscle stem cells impairs muscle regeneration. FTO promotes skeletal muscle differentiation and regeneration by directly targeting and regulating m6A-modified c-Myc, a well-known repressor of myogenesis. The IGF2BP2 reader protein recognizes m6A-modified c-Myc in undifferentiated myoblasts and stabilizes it. As FTO levels increase during myoblast differentiation, m6A levels on c-Myc decrease. This reduction prevents IGF2BP2 from binding to c-Myc, thereby destabilizing c-Myc levels and promoting differentiation. Overall, our findings underscore the significance of the novel FTO/c-Myc/IGF2BP2 axis in skeletal muscle differentiation and regeneration.

developmental biology↗

MicroRNA-24-3p promotes skeletal muscle differentiation and regeneration by regulating high mobility group AT-hook 1

Numerous studies have established the critical roles of microRNAs in regulating post-transcriptional gene expression in diverse biological processes. Here, we report on the role and mechanism of miR-24-3p in skeletal muscle differentiation and regeneration. miR-24-3p promotes myoblast differentiation and skeletal muscle regeneration by directly targeting high mobility group AT-hook 1 (HMGA1) and regulating it and its direct downstream target, the inhibitor of differentiation 3 (ID3). miR-24-3p knockdown in neonatal mice increases PAX7-positive proliferating muscle stem cells (MuSCs) by derepressing Hmga1 and Id3. Similarly, inhibition of miR-24-3p in the tibialis anterior muscle prevents Hmga1 and Id3 downregulation and impairs regeneration. These findings provide evidence that the miR-24-3p/HMGA1/ID3 axis is required for MuSC differentiation and skeletal muscle regeneration in vivo.

developmental biology↗

Determining the stages of cellular differentiation using Deep Ultraviolet Resonance Raman Spectroscopy

Cellular differentiation is a fundamental process in which one cell type changes into one or more specialized cell types. Cellular differentiation starts at the beginning of embryonic development when a simple zygote begins to transform into a complex multicellular organism composed of various cell and tissue types. This process continues into adulthood when adult stem cells differentiate into more specialized cells for normal growth, regeneration, repair, and cellular turnover. Any abnormalities associated with this fundamental process of cellular differentiation is linked to life threatening conditions including degenerative diseases and cancers. Detection of undifferentiated and different stages of differentiated cells can be used for disease diagnosis but is often challenging due to the laborious procedures, expensive tools, and specialized technical skills which are required. Here, a novel approach, called deep ultraviolet resonance Raman spectroscopy, is used to study various stages of cellular differentiation using a well-known myoblast cell line as a model system. These cells proliferate in the growth medium and spontaneously differentiate in differentiation medium into myocytes and later into myotubes and myofibers. The cellular and molecular characteristics of these cells mimic very well actual muscle tissue in vivo. We have found that undifferentiated myoblast cells and myoblast cells differentiated at three different stages are able to be easily separated using deep ultraviolet resonance Raman spectroscopy in combination with chemometric techniques. Our study has a great potential to study cellular differentiation during normal development as well as to detect abnormal cellular differentiation in human pathological conditions in future studies.

molecular biology↗

Single species RNA purification with DNA nanoswitches

We report a novel method to purify individual RNA species using programmable DNA nanoswitches to facilitate RNA capture, release, and isolation. We validate sequence-based purification of microRNA, rRNA, and an mRNA fragment from total RNA, demonstrate multiplexing with two different RNA species, and show an application with downstream LC/MS analysis to identify RNA modifications. The simplicity, low cost, and low sample requirements of our method make it suitable for easy adoption.Competing Interest StatementLZ, ARC, and KH have intellectual property related to DNA nanoswitches. All other authors declare no competing interests.View Full Text

molecular biology↗

Diagnosis of Duchenne Muscular Dystrophy using Raman Hyperspectroscopy

Duchenne muscular dystrophy (DMD) is the most common and severe form of muscular dystrophy and affects boys in infancy or early childhood. DMD is known to trigger progressive muscle weakness due to skeletal muscle degeneration and ultimately causes death. There are limited treatment regimens available that can either slow or stop the progression of DMD. An accurate and specific method for diagnosing DMD in its earliest stages is needed to prevent progressive muscle degeneration and death. Current methods for diagnosing DMD are often laborious, expensive, invasive, and typically diagnose the disease later on it is progression. In an effort to improve the accuracy and ease of diagnosis, this study focused on developing a novel method for diagnosing DMD which combines Raman hyperspectroscopic analysis of blood serum with advanced statistical analysis. Partial Least Squares Discriminant Analysis (PLS-DA), was applied to the spectral dataset acquired from control and mdx blood serum of 3- and 12-month old mice to build a diagnostic algorithm. Internal cross-validation showed 95.2% sensitivity and 94.6% specificity for identifying diseased spectra. These results were verified using external validation, which achieved 100% successful classification efficiency at the level of individual donor. This proof-of-concept study presents Raman hyperspectroscopic analysis of blood serum as a fast, non-expensive, minimally invasive and early detection method for the diagnosis of Duchenne muscular dystrophy.

pathology↗

Detection of cellular microRNAs with programmable DNA nanoswitches

MicroRNAs are short non-coding regulatory RNAs that are increasingly used as disease biomarkers. Detection of microRNAs can be arduous and expensive, and often requires amplification, labeling, or radioactive probes. Here we report a single-step, non-enzymatic detection assay using conformationally responsive DNA nanoswitches. Termed miRacles (microRNA activated conditional looping of engineered switches), our assay has sub-attomole sensitivity and single-nucleotide specificity using an agarose gel electrophoresis readout. We detect cellular microRNAs from nanogram-scale RNA extracts of differentiating muscle cells, and demonstrate multiplexed detection of several microRNAs from one biological sample. We demonstrate one-hour detection without expensive equipment or reagents, making this assay a compelling alternative to qPCR and Northern blotting.\n\nSignificance statementDetection of microRNAs play a key role in biological research and medical diagnostics, and current detection methods are expensive and require sophisticated processes. We present microRNA activated conditional looping of engineered switches (miRacles), a mix-and-read strategy that is based on conformational changes of DNA nanoswitches upon binding a target microRNA. MiRacles has a sensitivity of [~]4 copies/cell and specificity of a single nucleotide, and can be performed in one hour at a fraction of the cost of traditional microRNA detection techniques. Our method can also be multiplexed to detect multiple microRNAs from one biological sample. The minimalistic miRacles assay has immediate application in biomedical research and longer term potential as a clinical tool.

bioengineering↗