A mutation in the Pax-6 gene in rat small eye is associated with impaired migration of midbrain crest cells.
The rat small eye strain (rSey) lacks eyes and nose in the homozygote, and is similar to the mouse Sey strain with mutations in the Pax-6 gene. We isolated Pax-6 cDNA clones from an rSey homozygote library, and found an internal deletion of about 600 basepairs in the serine/threonine-rich domain. At the genomic level, a single base (G) insertion in an exon generates an abnormal 5' donor splice site, thereby producing the truncated mRNA. Anterior midbrain crest cells in the homozygous rSey embryos reached the eye rudiments but did not migrate any further to the nasal rudiments, suggesting that the Pax-6 gene is involved in conducting migration of neural crest cells from the anterior midbrain.
Matsuo
T
T
Department of Ophthalmology, Okayama University Medical School, Japan.
Osumi-Yamashita
N
N
Noji
S
S
Ohuchi
H
H
Koyama
E
E
Myokai
F
F
Matsuo
N
N
Taniguchi
S
S
Doi
H
H
Iseki
S
S
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics*; D004622:Embryo, Mammalian / Q000648:ultrastructure; D005091:Exons; D005124:Eye Abnormalities / Q000196:embryology; D005136:Eye Proteins; D018398:Homeodomain Proteins; D006720:Homozygote; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D009666:Nose / Q000002:abnormalities; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; D016133:Polymerase Chain Reaction; D051381:Rats; D011922:Rats, Mutant Strains; D017207:Rats, Sprague-Dawley; D012097:Repressor Proteins; D015183:Restriction Mapping; D017384:Sequence Deletion; D014157:Transcription Factors / Q000235:genetics
D017931:DNA Primers; D004268:DNA-Binding Proteins; D005136:Eye Proteins; D018398:Homeodomain Proteins; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; C000605732:Pax6 protein, mouse; C000605733:Pax6 protein, rat; D012097:Repressor Proteins; D014157:Transcription Factors