Structure, chromosomal location, and tissue-specific expression of the mouse opticin gene.
OBJECTIVE
To determine the structure, location, and tissue-specific expression of the mouse opticin gene (Optc) and to compare expression in the eye with that of Prelp, collagen II, and collagen IX.


METHODS
Expressed sequence tags (ESTs) to mouse opticin were identified and the full-length sequence obtained after PCR reactions using a 15-day-postconception (dpc) whole-mouse embryo cDNA library. The mouse chromosomal localization of Optc was determined by radiation hybrid mapping and its genomic structure determined using an Optc-containing BAC clone. Tissue-specific expression of opticin, PRELP, collagen II, and collagen IX mRNAs was investigated by in situ hybridization and by dot blot hybridization for opticin.


RESULTS
The Optc gene was localized to mouse chromosome 1 at 74.3 cM and consisted of seven exons spanning 10 kb. The Optc gene was less than 4 kb from the Prelp gene. In situ hybridization localized opticin mRNA exclusively to the presumptive ciliary body during development and to the nonpigmented ciliary epithelium of the adult mouse eye. Expression of Prelp was also detected in the nonpigmented ciliary epithelium of the adult eye. However, expression of collagen types II and IX was detected largely in the developing mouse eye, with type IX expression confined primarily to the presumptive ciliary body.


CONCLUSIONS
The Optc, Prelp, and fibromodulin (Fmod) genes form a cluster on mouse chromosome 1. Opticin may represent a marker for ciliary body differentiation. Continued expression of opticin in the adult mouse eye suggests functions other than that of putative regulator of vitreous collagen fibrillogenesis.
Takanosu
M
M
Department of Cell Biology, University of Alabama at Birmingham, 35294-0019, USA.
Boyd
T C
TC
Le Goff
M
M
Henry
S P
SP
Zhang
Y
Y
Bishop
P N
PN
Mayne
R
R
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D002875:Chromosomes / Q000235:genetics*; D002924:Ciliary Body / Q000196:embryology / Q000378:metabolism*; D003094:Collagen / Q000235:genetics / Q000378:metabolism; D020224:Expressed Sequence Tags; D016326:Extracellular Matrix Proteins / Q000235:genetics* / Q000378:metabolism; D005136:Eye Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D017403:In Situ Hybridization; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011509:Proteoglycans / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
D016326:Extracellular Matrix Proteins; D005136:Eye Proteins; D006023:Glycoproteins; C404108:OPTC protein, human; C498607:Optc protein, mouse; C096382:PRELP protein, human; C490748:Prelp protein, mouse; D011509:Proteoglycans; D012333:RNA, Messenger; D003094:Collagen