The molecular signature and cis-regulatory architecture of a C. elegans gustatory neuron.
Taste receptor cells constitute a highly specialized cell type that perceives and conveys specific sensory information to the brain. The detailed molecular composition of these cells and the mechanisms that program their fate are, in general, poorly understood. We have generated serial analysis of gene expression (SAGE) libraries from two distinct populations of single, isolated sensory neuron classes, the gustatory neuron class ASE and the thermosensory neuron class AFD, from the nematode Caenorhabditis elegans. By comparing these two libraries, we have identified >1000 genes that define the ASE gustatory neuron class on a molecular level. This set of genes contains determinants of the differentiated state of the ASE neuron, such as a surprisingly complex repertoire of transcription factors (TFs), ion channels, neurotransmitters, and receptors, as well as seven-transmembrane receptor (7TMR)-type putative gustatory receptor genes. Through the in vivo dissection of the cis-regulatory regions of several ASE-expressed genes, we identified a small cis-regulatory motif, the "ASE motif," that is required for the expression of many ASE-expressed genes. We demonstrate that the ASE motif is a binding site for the C2H2 zinc finger TF CHE-1, which is essential for the correct differentiation of the ASE gustatory neuron. Taken together, our results provide a unique view of the molecular landscape of a single neuron type and reveal an important aspect of the regulatory logic for gustatory neuron specification in C. elegans.
Etchberger
John F
JF
Howard Hughes Medical Institute, Department of Biochemistry and Molecular Biophysics, Columbia University Medical Center, New York, NY 10032, USA.
Lorch
Adam
A
Sleumer
Monica C
MC
Zapf
Richard
R
Jones
Steven J
SJ
Marra
Marco A
MA
Holt
Robert A
RA
Moerman
Donald G
DG
Hobert
Oliver
O
D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D001665:Binding Sites; D017173:Caenorhabditis elegans / Q000196:embryology / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism; D016384:Consensus Sequence; D004625:Embryo, Nonmammalian; D004627:Embryonic Induction / Q000235:genetics*; D020869:Gene Expression Profiling / Q000379:methods; D018507:Gene Expression Regulation, Developmental; D015723:Gene Library; D008954:Models, Biological; D008969:Molecular Sequence Data; D009475:Neurons, Afferent / Q000166:cytology* / Q000378:metabolism; D011485:Protein Binding; D012333:RNA, Messenger / Q000378:metabolism; D050436:Regulatory Elements, Transcriptional; D013650:Taste Buds / Q000166:cytology* / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D016335:Zinc Fingers / Q000502:physiology
C473313:CHE-1 protein, C elegans; D029742:Caenorhabditis elegans Proteins; D012333:RNA, Messenger; D014157:Transcription Factors