Neuron identity switches in response to the gradient gene expression pathway

Frontiers in Cellular Neuroscience, Journal Year: 2025, Volume and Issue: 19

Published: Feb. 19, 2025

Nonstatic Neuron identity emerges from the complementary synaptic transcriptional architecture shaped by neuron signaling and surrounding non-neuronal cells. When signals a series of neurons are combined, they form circuits through which information flows, brain functioning occurs as superposition these neural circuits. To ensure proper communication function, develop phenotypes axonal projections electrophysiological behaviors, creating gradients that define regions allocate neurochemical functions (Vogel et al., 2024).In mature nervous system, extend over long distances communicate with different well-established (Pal 2024) in both peripheral systems (PNS) central (CNS). Information flows inside each axon despite great distance, resulting immediate responses.The mechanism involved response has been described. The soma-centric notion is main idea for this mechanism, where neuronal soma provides total molecular (Dalla Costa 2021). However, Nijssen (2018) showed evidence differences between transcriptome Spinal Motor Neurons (MNs).Several authors suggest that, given differences, alone may not provide all transcriptomic information. Instead, glial cells accompanying along its pathway supply some These play an essential role function. 2021;Giuditta 2008).The described glia-to-axon relationship becomes particularly significant CNS, have distinct molecular, cellular, functional characteristics 2024;Siletti 2023). As axons various areas, their profiles differ soma's (Nijssen 2018). This variation suggests adapt to match local cellular environment traverse regions. specific resources area. We term space-dependent, dynamic adaptation "neuronal continuum."Modern neuroscience produced high-resolution cell classifications based on expression single-cell sequencing techniques such Single-Nucleus RNA (snRNA-seq) (Siletti technique focuses nuclei (Hodge 2019). atlases us CNS cartography most species 2023;Yao 2023;Chen 2023), typically report two groups neurons-glutamatergic GABAergic-together third lineage known glia, plays critical regulatory roles throughout (Liu 2023).Different cognitive region-associated require configurations axondendrite junctions 2021), determine how flows. physical pathways, dendrite morphology can change, crucial communication.Recent research shown changes often accompany regulation gene (Gao (2018), developed method single axon, similar snRNA-seq, called Axon-seq. They sequenced MNs, finding profile differs neuron. More interestingly, unique transcription factor signature was found distal any reported, leading questions: Who responsible switch, why does happen?Glial constitute half population mammalian system. glia-toneuron ratio varies across structures classified into types: astrocytes, microglia, synantocytes (Tizabi 2024), oligodendrocytes Schwann cells, last being myelin Similar scenarios exist PNS maintain close relationship. Glial residing at or within segments providing fundamental support survival 2023).Recent findings highlighted contribution show shifting sheaths (Xin Chan, 2020). also very diverse, varying subtypes proportions neighborhoods regions; neighborhood own types glia Giuditta (2008) mechanisms direct squid giant showing beyond simple soma/axon, content axon. Studies reported interact deliver genetic material machinery (Das Court demonstrated flow ribosomes Furthermore, recently other explained axons, describing exosome (cargo information) exchange oligodendrocyte-to-axonBesides neurons, reach up meter humans (Twiss Fainzilber, 2009), travel layers brain. frontotemporal arcuate fasciculus (AF) well-studied connects white matter bundle language processing 4-5 cm (Basile 2024).Despite delivery primary proposed mRNA transport Twiss (2009) anterograde rate only 16 mm/hour, suggesting relying solely nuclear synthesis insufficient due retrograde needed travel. observations highlight limitations nucleus axons.Gene were initially rostral-caudal direction (Fornito Lau (2021) shows gradual decay according distance mouse cortex. Vogel (2024), three principal axes aligned brain's anatomical architecture.In addition, snRNA-seq studies continuity major populations adult human brains 2023;Hodge 2019), type region.Current explores multiple scales (micro-meso-macro scales), defined informational unit. For example, mesoscale, unit would be set neighboring locally expression. From shared expression, emerge, i.e. morphology, interconnectivity (Poulin 2016). Each fuzzily self-defined space brain, will those boundaries shift dynamically microgradients. Individual whose cross sources thrive.Since scales, it plausible phenomenon individual neurons. region molecularly, cellularly, functionally patterns necessary cerebral function.While distances, visit change segment acquires soma, combining one supplied (Farias Such continuum means do but continuous collectively established dependent (Fig. 1).We propose oligodendrocytes, secondarily serve glia-to-axon, compartments PNS. Recent demonstrate regulating synapse development, transmission, plasticity 2023;Xin 2020).The impacts myelin-associated diseases disorders. compared healthy amyotrophic lateral sclerosis demonstrating differential 121 mRNAs property Also, oligodendrocyte heterogeneity implicated conditions Multiple Sclerosis.In typical demyelination disease, control patients could contribute inflammation (Jäkel possibly disruption certain derived missing subtypes. myelin-related impact commonly associated disorders (Murdock Tsai, By acknowledging spatially resources, we better understand complex interplay health disease.The traditional view possessing fixed intrinsic properties challenged emerging continuum. Figure 1. compartment switches function location moves, resembling neighborhood. A) distinct. B) Axonal pathways longer. connecting C) At beginning path, body begins pathway. On way, accompanied (and cells), maintained. D) Due relationship, occurs, where, transfer (Krämer-Albers Werner, segment, depends located. Giving rise proteins combined coming produces switch E) end pathway, compartments, non-static space-dependent "Neuronal Continuum."

Language: Английский

Asymmetries in the human brain

Handbook of clinical neurology, Journal Year: 2025, Volume and Issue: unknown, P. 15 - 36

Published: Jan. 1, 2025

Language: Английский