Calbindin D-28K immunoreactivity of human cone cells varies with retinal position.
Calbindin D-28K is a calcium-binding protein found in the cone but not rod photoreceptor cells in the retinas of a variety of species. Recent studies of the monkey retina indicated that calbindin D-28K may be expressed preferentially in non-foveal regions of the retina. In the current studies of human retinas, immunohistochemical experiments demonstrated that calbindin D-28K is reduced or absent in the fovea and parafovea, but prevalent in the perifovea and periphery. These findings were supported by the quantification of calbindin D-28K in 1-mm trephine punches obtained from different regions of the human retina. The specificity of the anti-calbindin D-28K antibodies used in these studies was confirmed by Western blot analysis using purified calbindin D-28K. The protein was purified from retinal tissue and its identity confirmed by partial amino-acid sequence analysis. The expression of calbindin D-28K did not correlate with the spectral properties of the cones, rather to their position in the retina. The study of spatially expressed genes, like the one encoding calbindin D-28K, may help explain the patterns of retinal degeneration seen in some human cone-rod dystrophies.
Haley
T L
TL
R.S. Dow Neurological Sciences Institute, Good Samaritan Hospital and Medical Center, Portland.
Pochet
R
R
Baizer
L
L
Burton
M D
MD
Crabb
J W
JW
Parmentier
M
M
Polans
A S
AS
D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D000918:Antibody Specificity; D015153:Blotting, Western; D064026:Calbindins; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry; D012160:Retina / Q000737:chemistry / Q000378:metabolism*; D017949:Retinal Cone Photoreceptor Cells / Q000378:metabolism*; D012168:Retinal Pigments / Q000378:metabolism; D064030:S100 Calcium Binding Protein G / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*
D064026:Calbindins; D009419:Nerve Tissue Proteins; D010446:Peptide Fragments; D012168:Retinal Pigments; D064030:S100 Calcium Binding Protein G