Molecular cloning of a putative voltage- and cyclic nucleotide-gated ion channel present in the antennae and eyes of Drosophila melanogaster.
The amino acid sequence BCNG-1 (brain cyclic nucleotide gated 1, of the mouse), the first member of mamalian I(h) channels, was used to construct a set of polymerase chain reaction (PCR) primers from possibly conserved regions. Reverse transcription-PCR with Drosophila melanogaster mRNA yielded in a PCR product, which exhibited a high homology to BCNG-1. Using these PCR products to screen a D. melanogaster head cDNA library we isolated a cDNA encoding a member of a new class of putative voltage- and cyclic nucleotide-gated potassium channels from D. melanogaster. The most important features of the amino acid sequence predicted from the cDNA were a C-terminal cyclic nucleotide-binding region, an S4-voltage sensor and a putative potassium-selective pore-forming motif. The high homology of 51% to the sea urchin I(h) channel, which belongs to the same class of ion channels as BCNG-1, leads us to suggest that the Drosophila cDNA is the first insect member of a new class of hyperpolarization-activated and cyclic nucleotide-gated channels. As shown by in situ hybridization, a pronounced mRNA expression was detected in neuronal tissue, including sensory tissue like the compound eyes, and the olfactory and the auditory organs.
Marx
T
T
Ruhr-Universität-Bochum, Fakultät für Biologie, Lehrstuhl für Zellphysiologie, ND4, Universitätsstr150, D-44780 Bochum, Germany.
Gisselmann
G
G
Störtkuhl
K F
KF
Hovemann
B T
BT
Hatt
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015220:Calcium Channels / Q000235:genetics*; D003001:Cloning, Molecular; D054815:Cyclic Nucleotide-Gated Cation Channels; D018076:DNA, Complementary; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000166:cytology / Q000235:genetics*; D005123:Eye / Q000166:cytology / Q000378:metabolism; D015870:Gene Expression; D017344:Genes, Insect; D017403:In Situ Hybridization; D007473:Ion Channels; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins; D009475:Neurons, Afferent / Q000166:cytology / Q000378:metabolism*; D015221:Potassium Channels / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012689:Sequence Homology, Nucleic Acid
D015220:Calcium Channels; C090451:CngA protein, Drosophila; D054815:Cyclic Nucleotide-Gated Cation Channels; D018076:DNA, Complementary; D029721:Drosophila Proteins; D007473:Ion Channels; D009419:Nerve Tissue Proteins; D015221:Potassium Channels; D012333:RNA, Messenger