Light-emitting properties of recombinant semi-synthetic aequorins and recombinant fluorescein-conjugated aequorin for measuring cellular calcium.
15 kinds of recombinant semi-synthetic aequorins and a recombinant fluorescein-conjugated aequorin were prepared and their properties in Ca(2+)-triggered luminescence were studied. The semi-synthetic aequorins showed a wide range of Ca(2+)-sensitivity. The luminescence intensity of a high-sensitivity type (hcp-aequorin) was greater than 10(4)-times that of a low-sensitivity type (n-aequorin) at pCa 6.0-6.5. The fluorescein-conjugated aequorin exhibited fluorescence in addition to the Ca(2+)-triggered luminescence, thus it can be used to visualize the diffusion and distribution of aequorin in cells. The data obtained, particularly the Ca(2+)-sensitivity curves, are useful in selecting a suitable semi-synthetic aequorin for an experiment.
Shimomura
O
O
Marine Biological Laboratory, Woods Hole, Massachusetts.
Musicki
B
B
Kishi
Y
Y
Inouye
S
S
D000331:Aequorin / Q000031:analogs & derivatives / Q000737:chemistry* / Q000187:drug effects / Q000235:genetics; D002118:Calcium / Q000032:analysis* / Q000494:pharmacology; D019793:Fluorescein; D005452:Fluoresceins; D005453:Fluorescence; D005470:Fluorometry; D008163:Luminescent Measurements; D010783:Photometry / Q000379:methods*; D011994:Recombinant Proteins / Q000737:chemistry* / Q000187:drug effects
D005452:Fluoresceins; D011994:Recombinant Proteins; D000331:Aequorin; D002118:Calcium; D019793:Fluorescein