bioRxiv Science⌕ Search

Biology subjects

Silagi, E. S.

Publications and source records attributed to Silagi, E. S..

2 recordsLinked to original sources

Profiling local translatomes and RNA binding proteins of somatosensory neuronsreveals specializations of individual axons

Neurons extend long axons that traverse distinct microenvironments, yet how these compartments acquire and maintain specialized molecular identities remains unclear. Here, we use spatial translatomics to define the local axonal translatomes of dorsal root ganglion (DRG) neurons that mediate somatosensation. Translating Ribosome Affinity Purification and RNA sequencing revealed thousands of mRNAs that are preferentially translated within the central axons, peripheral axons, or DRG soma, establishing compartment-specific translational programs. Many of these transcripts encode ion channels, neurotransmitter receptors, and structural proteins that confer distinct electrophysiological, synaptic, and regenerative properties to each axon. Cross-dataset integration with single-cell RNA-seq demonstrated that neuropathic injury elicits highly compartment-specific remodeling of these localized translational programs. We identify polarized RNA regulons coordinated by the RNA-binding proteins (RBPs) SFPQ and SRSF10, which preferentially bind and traffic mRNAs to the peripheral or central axon, respectively. These findings reveal a mechanistic framework in which RBP-guided RNA sorting and local translation establish and dynamically tune subcellular specialization in sensory neurons. HIGHLIGHTSO_LIDistinct mRNAs are translated in peripheral or central axons (painseq.shinyapps.io/CompartmentTRAP/). C_LIO_LIAxonal translatomes enable localized regulation of electrophysiology, neuronal plasticity, and regeneration. C_LIO_LIThe RBPs, SFPQ and SRSF10, enable mRNA sorting to peripheral and central axons respectively. C_LI

neuroscience↗

GLUT1 is redundant in hypoxic and glycolytic nucleus pulposus cells of the intervertebral disc

Glycolysis is central to homeostasis of nucleus pulposus (NP) cells in the avascular intervertebral disc. Since the glucose importer, GLUT1, is a highly enriched phenotypic marker of NP cells, we hypothesized that it is vital for the development and post-natal maintenance of the disc. Surprisingly, primary NP cells treated with two well-characterized GLUT1 inhibitors maintained normal rates of glycolysis and ATP production, indicating intrinsic compensatory mechanisms. We show in vitro that NP cells mitigate GLUT1 loss by rewiring glucose import through GLUT3. Noteworthy, we demonstrate that substrates, such as glutamine and palmitate, do not compensate for glucose restriction resulting from dual inhibition of GLUT1/3 and inhibition compromises long-term cell viability. To investigate the redundancy of GLUT1 function in NP, we generated two NP-specific knockout mice: Krt19CreERT; Glut1f/f and Foxa2Cre; Glut1f/f. Noteworthy, there were no apparent defects in post-natal disc health or development and maturation in mutant mice. Microarray analysis confirmed that GLUT1 loss did not cause transcriptomic alterations in the NP, supporting that cells are refractory to GLUT1 loss. These observations provide the first evidence of functional redundancy in GLUT transporters in the physiologically hypoxic intervertebral disc and underscore the importance of glucose as the indispensable substrate for NP cells.

cell biology↗