Visual pigments of marine carnivores: pinnipeds, polar bear, and sea otter.
Rod and cone visual pigments of 11 marine carnivores were evaluated. Rod, middle/long-wavelength sensitive (M/L) cone, and short-wavelength sensitive (S) cone opsin (if present) sequences were obtained from retinal mRNA. Spectral sensitivity was inferred through evaluation of known spectral tuning residues. The rod pigments of all but one of the pinnipeds were similar to those of the sea otter, polar bear, and most other terrestrial carnivores with spectral peak sensitivities (lambda(max)) of 499 or 501 nm. Similarly, the M/L cone pigments of the pinnipeds, polar bear, and otter had inferred lambda(max) of 545 to 560 nm. Only the rod opsin sequence of the elephant seal had sensitivity characteristic of adaptation for vision in the marine environment, with an inferred lambda(max) of 487 nm. No evidence of S cones was found for any of the pinnipeds. The polar bear and otter had S cones with inferred lambda(max) of approximately 440 nm. Flicker-photometric ERG was additionally used to examine the in situ sensitivities of three species of pinniped. Despite the use of conditions previously shown to evoke cone responses in other mammals, no cone responses could be elicited from any of these pinnipeds. Rod photoreceptor responses for all three species were as predicted by the genetic data.
Scripps Institution of Oceanography, UCSD, La Jolla, CA, USA. dlevenson@ucsd.edu
David H
DH
Levenson
Paul J
PJ
Ponganis
Michael A
MA
Crognale
Jess F
JF
Deegan
Andy
A
Dizon
Gerald H
GH
Jacobs
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D010872:Caniformia; D002335:Carnivora / Q000502:physiology*; D004596:Electroretinography; D010041:Otters; D010802:Phylogeny; D017949:Retinal Cone Photoreceptor Cells / Q000737:chemistry / Q000502:physiology; D012168:Retinal Pigments / Q000235:genetics / Q000502:physiology*; D017948:Retinal Rod Photoreceptor Cells / Q000737:chemistry / Q000502:physiology; D013045:Species Specificity; D013057:Spectrum Analysis; D001503:Ursidae
D012168:Retinal Pigments