ABSTRACT
Glial cells in the central nervous system (CNS) are composed of oligodendrocytes, astrocytes and microglia. They contribute more than half of the total cells of the CNS, and are essential for neural development and functioning. Studies on the fate specification, differentiation, and functional diversification of glial cells mainly rely on the proper use of cell- or stage-specific molecular markers. However, as cellular markers often exhibit different specificity and sensitivity, careful consideration must be given prior to their application to avoid possible confusion. Here, we provide an updated overview of a list of well-established immunological markers for the labeling of central glia, and discuss the cell-type specificity and stage dependency of their expression.
Subject(s)
Neuroglia/metabolism , Central Nervous System , Oligodendroglia/metabolism , Astrocytes/metabolism , MicrogliaABSTRACT
Noxious mechanical information is transmitted through molecularly distinct nociceptors, with pinprick-evoked sharp sensitivity via A-fiber nociceptors marked by developmental expression of the neuropeptide Y receptor 2 (Npy2r) and von Frey filament-evoked punctate pressure information via unmyelinated C fiber nociceptors marked by MrgprD. However, the molecular programs controlling their development are only beginning to be understood. Here we demonstrate that Npy2r-expressing sensory neurons are in fact divided into two groups, based on transient or persistent Npy2r expression. Npy2r-transient neurons are myelinated, likely including A-fiber nociceptors, whereas Npy2r-persistent ones belong to unmyelinated pruriceptors that co-express Nppb. We then showed that the transcription factors NFIA and Runx1 are necessary for the development of Npy2r-transient A-fiber nociceptors and MrgprD C-fiber nociceptors, respectively. Behaviorally, mice with conditional knockout of Nfia, but not Runx1 showed a marked attenuation of pinprick-evoked nocifensive responses. Our studies therefore identify a transcription factor controlling the development of myelinated nociceptors.
ABSTRACT
Oligodendrocytes (OLs) are myelinating glial cells that form myelin sheaths around axons to ensure rapid and focal conduction of action potentials. Here, we found that an axonal outgrowth regulatory molecule, AATYK (apoptosis-associated tyrosine kinase), was up-regulated with OL differentiation and remyelination. We therefore studied its role in OL differentiation. The results showed that AATYK knockdown inhibited OL differentiation and the expression of myelin genes in vitro. Moreover, AATYK-deficiency maintained the proliferation status of OLs but did not affect their survival. Thus, AATYK is essential for the differentiation of OLs.
Subject(s)
Animals , Mice , Rats , Animals, Newborn , Apoptosis Regulatory Proteins , Genetics , Metabolism , Cell Differentiation , Physiology , Cell Proliferation , Genetics , Cells, Cultured , Cuprizone , Toxicity , Demyelinating Diseases , Metabolism , Pathology , Embryo, Mammalian , Gene Expression Regulation, Developmental , Genetics , Ki-67 Antigen , Metabolism , Mice, Inbred C57BL , Myelin Basic Protein , Metabolism , Myelin Proteolipid Protein , Metabolism , Myelin Sheath , Metabolism , Oligodendroglia , Metabolism , Protein-Tyrosine Kinases , Genetics , Metabolism , RNA, Small Interfering , Genetics , Metabolism , Rats, Sprague-DawleyABSTRACT
Bone morphogenetic protein 7 [BMP7]has been suggested to play a protecOriginal Article tive role against kidney injury in chronic kidney disease. To identify the critical molecular regulators in the early stage of diabetic ne-phropathy, we studied the expression of BMP? and 2 important kidney-specific markers, podocin and Tamm-Horsfall protein [THP]. A diabetic nephropathy model was established by intraperitone-ally injecting streptozotocin [STZ] in male Kunming mice. Kidney weight index was used as an indicator of early renal injury. Kidney tissue from the diabetic model mice was obtained at 4, 8, and 12 weeks, and total protein was extracted to assess the expression of BMP?, podocin, and THP by western blot analysis. Diabetic model mice were successfully established, and the kidney weight index of the model animals increased significantly. The expression of BMP? was significantly downregulated, while the expression of THP was increased in the early stage of diabetic nephropathy. However, the expression of podocin did not change. Our observations suggested that down-regulation of BMP? expression and up-regulation of THP expression were early events that occur prior to podocyte injury with the structure protein, podocin spoiled, which further confirmed that BMP? is a key molecular regulator in the early stage of diabetic nephropathy