Rho B-crystallin, an aldose reductase-like lens protein in the gecko Lepidodactylus lugubris.
The ocular lenses of the diurno-nocturnal gecko Lepidodactylus lugubris contain a monomeric 38-kDa protein at a level of 20 to 22% of the total water-soluble protein. Amino acid sequences of peptides from this protein are most similar--up to 72% identity--to mammalian aldose reductase, an NADPH-dependent reductase which normally occurs at house-keeping levels in the eye lens, and which is involved in the development of diabetic cataract. The sequences show 56% identity with rho-crystallin from lenses of the frog genus Rana. It is concluded that different genes from the same superfamily of NADPH-dependent reductases have been recruited to become highly expressed as lens proteins in at least two different evolutionary lineages. To reflect the relationship with frog rho-crystallin, the gecko lens protein is designated as rho B-crystallin. As for frog rho-crystallin, no enzymatic activity could be established for rho B-crystallin in the gecko lens. Up to now, rho B-crystallin has not been detected in lenses of other reptiles or amphibians.
Röll
B
B
Lehrstuhl für Tierphysiologie, Fakultät für Biologie, Ruhr-Universität Bochum, Germany.
van Boekel
M A
MA
Amons
R
R
de Jong
W W
WW
D000449:Aldehyde Reductase / Q000737:chemistry*; D000595:Amino Acid Sequence; D000818:Animals; D003459:Crystallins / Q000737:chemistry / Q000145:classification*; D007908:Lens, Crystalline / Q000201:enzymology*; D008116:Lizards / Q000502:physiology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000737:chemistry; D011898:Ranidae / Q000502:physiology; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity
D003459:Crystallins; D010446:Peptide Fragments; D000449:Aldehyde Reductase