Zebrafish TRPA1 channels are required for chemosensation but not for thermosensation or mechanosensory hair cell function.
Transient receptor potential (TRP) ion channels have been implicated in detecting chemical, thermal, and mechanical stimuli in organisms ranging from mammals to Caenorhabditis elegans. It is well established that TRPA1 detects and mediates behavioral responses to chemical irritants. However, the role of TRPA1 in detecting thermal and mechanical stimuli is controversial. To further clarify the functions of TRPA1 channels in vertebrates, we analyzed their roles in zebrafish. The two zebrafish TRPA1 paralogs are expressed in sensory neurons and are activated by several chemical irritants in vitro. High-throughput behavioral analyses of trpa1a and trpa1b mutant larvae indicate that TRPA1b is necessary for behavioral responses to these chemical irritants. However, TRPA1 paralogs are not required for behavioral responses to temperature changes or for mechanosensory hair cell function in the inner ear or lateral line. These results support a role for zebrafish TRPA1 in chemical but not thermal or mechanical sensing, and establish a high-throughput system to identify genes and small molecules that modulate chemosensation, thermosensation, and mechanosensation.
Prober
David A
DA
Department of Molecular and Cellular Biology, Center for Brain Science, Harvard Stem Cell Institute, Harvard University, Cambridge, Massachusetts 02138, USA. prober@fas.harvard.edu
Zimmerman
Steven
S
Myers
Benjamin R
BR
McDermott
Brian M
BM
Kim
Seok-Hyung
SH
Caron
Sophie
S
Rihel
Jason
J
Solnica-Krezel
Lilianna
L
Julius
David
D
Hudspeth
A J
AJ
Schier
Alexander F
AF
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D002460:Cell Line; D002478:Cells, Cultured; D002628:Chemoreceptor Cells / Q000502:physiology*; D005260:Female; D006580:Genetic Carrier Screening; D006198:Hair Cells, Auditory / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D007473:Ion Channels / Q000235:genetics / Q000502:physiology*; D007814:Larva / Q000235:genetics / Q000502:physiology; D008465:Mechanoreceptors / Q000502:physiology*; D008969:Molecular Sequence Data; D009149:Mustard Plant / Q000633:toxicity; D009154:Mutation; D010938:Plant Oils / Q000633:toxicity; D000074025:TRPA1 Cation Channel; D013823:Thermoreceptors / Q000502:physiology*; D050051:Transient Receptor Potential Channels; D014982:Xenopus laevis; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000235:genetics / Q000502:physiology*
D007473:Ion Channels; D010938:Plant Oils; D000074025:TRPA1 Cation Channel; D050051:Transient Receptor Potential Channels; D029961:Zebrafish Proteins; C494579:trpa1a protein, zebrafish; C027793:mustard oil