Abstract
Null mutations in the transient receptor potential (trp) gene eliminate the major, Ca2+-selective component of the light-sensitive conductance in Drosophila photoreceptors. Although it is the prototypical member of the TRP ion channel superfamily, conclusive evidence that TRP is a pore-forming channel subunit in vivo is lacking. We show here that mutating a specific acidic residue (Asp621) in the putative pore virtually eliminated Ca2+ permeation in vivo and altered other biophysical properties of the native TRP conductance. The results identify Asp621 as a critical residue of the TRP Ca2+ selectivity filter, provide the first rigorous demonstration that a TRP protein is a pore-forming subunit in any native system, and point to the likely location of the pore in mammalian canonical TRP channels. The specific elimination of Ca2+ permeation in TRP also provided a unique opportunity to address the roles of Ca2+ influx in vivo. We found that Asp621 mutations profoundly affected several key aspects of the light response and caused light-dependent retinal degeneration.
| Original language | English |
|---|---|
| Pages (from-to) | 604-615 |
| Number of pages | 12 |
| Journal | Journal of Neuroscience |
| Volume | 27 |
| Issue number | 3 |
| DOIs | |
| State | Published - Jan 17 2007 |
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Keywords
- Calcium channel
- Permeability
- Photoreceptor
- Pore
- Retinal degeneration
- TRP channels
- TRPC
ASJC Scopus subject areas
- Neuroscience(all)
Cite this
In vivo identification and manipulation of the Ca2+ selectivity filter in the Drosophila transient receptor potential channel. / Liu, Che H.; Wang, Tao; Postma, Marten; Obukhov, Alexander; Montell, Craig; Hardie, Roger C.
In: Journal of Neuroscience, Vol. 27, No. 3, 17.01.2007, p. 604-615.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - In vivo identification and manipulation of the Ca2+ selectivity filter in the Drosophila transient receptor potential channel
AU - Liu, Che H.
AU - Wang, Tao
AU - Postma, Marten
AU - Obukhov, Alexander
AU - Montell, Craig
AU - Hardie, Roger C.
PY - 2007/1/17
Y1 - 2007/1/17
N2 - Null mutations in the transient receptor potential (trp) gene eliminate the major, Ca2+-selective component of the light-sensitive conductance in Drosophila photoreceptors. Although it is the prototypical member of the TRP ion channel superfamily, conclusive evidence that TRP is a pore-forming channel subunit in vivo is lacking. We show here that mutating a specific acidic residue (Asp621) in the putative pore virtually eliminated Ca2+ permeation in vivo and altered other biophysical properties of the native TRP conductance. The results identify Asp621 as a critical residue of the TRP Ca2+ selectivity filter, provide the first rigorous demonstration that a TRP protein is a pore-forming subunit in any native system, and point to the likely location of the pore in mammalian canonical TRP channels. The specific elimination of Ca2+ permeation in TRP also provided a unique opportunity to address the roles of Ca2+ influx in vivo. We found that Asp621 mutations profoundly affected several key aspects of the light response and caused light-dependent retinal degeneration.
AB - Null mutations in the transient receptor potential (trp) gene eliminate the major, Ca2+-selective component of the light-sensitive conductance in Drosophila photoreceptors. Although it is the prototypical member of the TRP ion channel superfamily, conclusive evidence that TRP is a pore-forming channel subunit in vivo is lacking. We show here that mutating a specific acidic residue (Asp621) in the putative pore virtually eliminated Ca2+ permeation in vivo and altered other biophysical properties of the native TRP conductance. The results identify Asp621 as a critical residue of the TRP Ca2+ selectivity filter, provide the first rigorous demonstration that a TRP protein is a pore-forming subunit in any native system, and point to the likely location of the pore in mammalian canonical TRP channels. The specific elimination of Ca2+ permeation in TRP also provided a unique opportunity to address the roles of Ca2+ influx in vivo. We found that Asp621 mutations profoundly affected several key aspects of the light response and caused light-dependent retinal degeneration.
KW - Calcium channel
KW - Permeability
KW - Photoreceptor
KW - Pore
KW - Retinal degeneration
KW - TRP channels
KW - TRPC
UR - http://www.scopus.com/inward/record.url?scp=33846451767&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33846451767&partnerID=8YFLogxK
U2 - 10.1523/JNEUROSCI.4099-06.2007
DO - 10.1523/JNEUROSCI.4099-06.2007
M3 - Article
C2 - 17234592
AN - SCOPUS:33846451767
VL - 27
SP - 604
EP - 615
JO - Journal of Neuroscience
JF - Journal of Neuroscience
SN - 0270-6474
IS - 3
ER -