Structural domains required for channel function of the mouse transient receptor potential protein homologue TRP1beta.
Transient receptor potential proteins (TRP) are supposed to participate in the formation of store-operated Ca(2+) influx channels by co-assembly. However, little is known which domains facilitate the interaction of subunits. Contribution of the N-terminal coiled-coil domain and ankyrin-like repeats and the putative pore region of the mouse TRP1beta (mTRP1beta) variant to the formation of functional cation channels were analyzed following overexpression in HEK293 (human embryonic kidney) cells. MTRP1beta expressing cells exhibited enhanced Ca(2+) influx and enhanced whole-cell membrane currents compared to mTRP1beta deletion mutants. Using a yeast two-hybrid assay only the coiled-coil domain facilitated homodimerization of the N-terminus. These results suggest that the N-terminus of mTRP1beta is required for structural organization thus forming functional channels.
Universität Bielefeld, Fakultät für Chemie, Biochemie II, Universitätsstrasse 25, D-33615, Bielefeld, Germany.
Michael
M
Engelke
Olaf
O
Friedrich
Petra
P
Budde
Christina
C
Schäfer
Ursula
U
Niemann
Christof
C
Zitt
Eberhard
E
Jüngling
Oliver
O
Rocks
Andreas
A
Lückhoff
Jürgen
J
Frey
D000818:Animals; D015220:Calcium Channels / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D019281:Dimerization; D017353:Gene Deletion; D006801:Humans; D008564:Membrane Potentials / Q000502:physiology; D051379:Mice; D009154:Mutation; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D020449:Repetitive Sequences, Amino Acid; D050052:TRPC Cation Channels; D014162:Transfection; D020798:Two-Hybrid System Techniques
D015220:Calcium Channels; D050052:TRPC Cation Channels; C096351:transient receptor potential cation channel, subfamily C, member 1