RT Journal Article SR Electronic T1 c-Maf Is Required for the Development of Dorsal Horn Laminae III/IV Neurons and Mechanoreceptive DRG Axon Projections JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 5362 OP 5373 DO 10.1523/JNEUROSCI.6239-11.2012 VO 32 IS 16 A1 Jia Hu A1 Tianwen Huang A1 Tingting Li A1 Zhen Guo A1 Leping Cheng YR 2012 UL http://www.jneurosci.org/content/32/16/5362.abstract AB Establishment of proper connectivity between peripheral sensory neurons and their central targets is required for an animal to sense and respond to various external stimuli. Dorsal root ganglion (DRG) neurons convey sensory signals of different modalities via their axon projections to distinct laminae in the dorsal horn of the spinal cord. In this study, we found that c-Maf was expressed predominantly in the interneurons of laminae III/IV, which primarily receive inputs from mechanoreceptive DRG neurons. In the DRG, c-Maf+ neurons also coexpressed neurofilament-200, a marker for the medium- and large-diameter myelinated afferents that transmit non-noxious information. Furthermore, mouse embryos deficient in c-Maf displayed abnormal development of dorsal horn laminae III/IV neurons, as revealed by the marked reduction in the expression of several marker genes for these neurons, including those for transcription factors MafA and Rora, GABAA receptor subunit α5, and neuropeptide cholecystokinin. In addition, among the four major subpopulations of DRG neurons marked by expression of TrkA, TrkB, TrkC, and MafA/GFRα2/Ret, c-Maf was required selectively for the proper differentiation of MafA+/Ret+/GFRα2+ low-threshold mechanoreceptors (LTMs). Last, we found that the central and peripheral projections of mechanoreceptive DRG neurons were compromised in c-Maf deletion mice. Together, our results indicate that c-Maf is required for the proper development of MafA+/Ret+/GFRα2+ LTMs in the DRG, their afferent projections in the dorsal horn and Pacinian corpuscles, as well as neurons in laminae III/IV of the spinal cord.