On June 20, 2012, The Journal of Neuroscience published online a research article entitled "Tlx1/3 and Ptf1a control the expression of distinct sets of transmitter and peptide receptor genes in the developing dorsal spinal cord" and highlighted this article at "This Week in The Journal". This work was mainly carried out by graduate students Zhen Guo, Congling Zhao, and Menggui Huang, under the supervision of Dr. Leping Cheng.

　　Establishing the pattern of expression of transmitters and peptides as well as their receptors in different neuronal types is crucial for understanding circuitry in the nervous system. The dorsal horn of the spinal cord is an integrative center that transmits and processes diverse somatosensory information. The neurons in the dorsal spinal cord can be grouped into excitatory and inhibitory neurons that respectively use glutamate and GABA/glycine as their fast transmitters. Previous studies have shown that some peptide genes are expressed in glutamatergic or GABAergic neurons and that transcription factors coordinate the transmitter phenotype and peptidergic fate in the dorsal horn. However, relatively little is known about whether transmitter and peptide receptors are expressed in a cell type specific manner in the dorsal horn and how they are controlled.

　　We screened the gene expression of 78 receptors in the spinal dorsal horn by in situ hybridization. We found that a distinct set of receptor genes were preferentially expressed in glutamatergic neurons and that deletion of Tlx1 and Tlx3 resulted in the loss of expression of these receptor genes. Furthermore, we obtained genetic evidence that Lbx1 and Ptf1a played roles in controlling the expression of some of the receptor genes. We also found that another distinct set of receptor genes were mainly expressed in GABAergic neurons in the spinal dorsal horn, and that their expression required the presence of Ptf1a and Pax2. Additionally, Tlx1/3 were required for the proper expression of some receptors in GABAergic neurons. These findings indicate that distinct sets of transmitter and peptide receptor genes are enriched in glutamatergic or GABAergic neurons and that Tlx1/3 and Ptf1a, the key transcription factors for fate determination of glutamatergic and GABAergic neurons in the dorsal spinal cord, also coordinate the expression of these receptor genes.

　　This work was supported by the 973 Program of The Ministry of Science and Technology of China and the “Strategic Priority Research Program” of the Chinese Academy of Sciences.

　　A model for the roles of transcription factors in controlling the expression of transmitter and peptide receptor genes in the dorsal spinal cord.