Isolation and investigation of canine phosducin as a candidate for canine generalized progressive retinal atrophies.
A subtractive cDNA cloning strategy was used to isolate canine retina-specific genes. Canine phosducin cDNA was cloned from a canine subtracted retinal cDNA library and was analysed as a candidate for canine generalized progressive retinal atrophies (gPRA). Canine phosducin cDNA is 1230 bp in length encoding 245 amino acids. The nucleotide and amino acid sequences of canine phosducin are highly conserved when compared with those of five other mammalian species, namely human, cat, cow, rat, and mouse. Northern blot analysis demonstrated that the mRNA transcript for phosducin was approximately 1.3 kb in size and was present in canine retina, but showed no visible signals in 13 other canine tissues. The phosducin gene was examined for polymorphisms in a total of 101 pedigree dogs of eight breeds, including normal, obligate gPRA carriers, and gPRA-affected dogs, by single-stranded conformation polymorphisms (SSCP) analysis. Polymorphisms in the phosducin gene were detected only in the 3' untranslated region of the gene in two breeds of dogs: allelic heterozygous polymorphisms in miniature poodles suffering from one form of gPRA (progressive rod-cone degeneration, prcd), and a different polymorphism in a single normal Irish wolfhound. The polymorphisms of phosducin in prcd-affected miniature poodles did not segregate with the autosomal recessive form of gPRA. Heterozygous inheritance of the polymorphisms suggests that phosducin is very unlikely to carry the mutation causing prcd, so phosducin was probably excluded as a candidate for prcd-affected miniature poodles in this study.
Lin
C T
CT
Department of Clinical Veterinary Medicine, Centre for Veterinary Science, University of Cambridge, U.K.
Petersen-Jones
S M
SM
Sargan
D R
DR
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002415:Cats; D018076:DNA, Complementary / Q000235:genetics; D004285:Dogs; D005136:Eye Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D020555:GTP-Binding Protein Regulators; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D012162:Retinal Degeneration / Q000235:genetics* / Q000503:physiopathology / Q000662:veterinary*; D013045:Species Specificity
D018076:DNA, Complementary; D005136:Eye Proteins; D020555:GTP-Binding Protein Regulators; D010750:Phosphoproteins; D012333:RNA, Messenger; C065631:phosducin