Expression of a chondroitin sulfate proteoglycan, versican (PG-M), during development of rat cornea.
OBJECTIVE
To understand the role of chondroitin sulfate proteoglycans during the development of rat cornea, expression of chondroitin sulfate and versican (PG-M) was studied.


METHODS
Chondroitin sulfate and keratan sulfate in rat cornea were analyzed by immunohistochemical techniques. Reverse transcription polymerase chain reaction (RT-PCR) for chondroitin sulfate proteoglycans was performed. Versican expression was studied by RT-PCR, immunohistochemical, and dot blot analyses. Expression of hyaluronan was evaluated histochemically using biotinylated hyaluronan binding protein.


RESULTS
Chondroitin sulfate was abundant in rat cornea at postnatal day 1 (P1) and became undetectable at P14. RT-PCR analysis showed that versican mRNA was highly expressed at P1 but was little expressed at P42. mRNAs for other chondroitin sulfate proteoglycans including biglycan, aggrecan, and decorin did not change much between P1 and P42. Expression for all versican splicing isoforms (V0-V3) was detectable from P1 through P14 but was undetectable after P21. mRNA for V0, the largest form with many chondroitin sulfate binding sites, decreased markedly in early stages from P1 to P14, whereas mRNA for V3, the shortest form with no chondroitin sulfate binding site, increased. mRNAs for middle-sized forms, V1 and V2, remained little changed during these periods. Immunohistochemical and dot blot analyses showed that versican is highly expressed at early stages of development and little expressed at adulthood. Similarly, hyaluronan, a versican-bound glycosaminoglycan, was highly expressed at early stages and little expressed at adulthood.


CONCLUSIONS
Versican and hyaluronan, which can form a large molecular complex, may play an important role in the early phase of corneal development.
Koga
Takahisa
T
Departments of Ophthalmology and Visual Science and Molecular Genetics, Kumamoto University Graduate School of Medical Sciences, Honjo 2-2-1, Kumamoto 860-0811, Japan. takakoga@fc.kuh.kumamoto-u.ac.jp
Inatani
Masaru
M
Hirata
Akira
A
Inomata
Yasuya
Y
Zako
Masahiro
M
Kimata
Koji
K
Oohira
Atsuhiko
A
Gotoh
Tomomi
T
Mori
Masataka
M
Tanihara
Hidenobu
H
D000375:Aging / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development* / Q000378:metabolism*; D011508:Chondroitin Sulfate Proteoglycans / Q000235:genetics / Q000378:metabolism*; D003315:Cornea / Q000254:growth & development* / Q000378:metabolism*; D006820:Hyaluronic Acid / Q000378:metabolism; D007150:Immunohistochemistry; D037181:Lectins, C-Type; D011509:Proteoglycans / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D053675:Versicans
D011508:Chondroitin Sulfate Proteoglycans; D037181:Lectins, C-Type; D011509:Proteoglycans; D012333:RNA, Messenger; C508324:Vcan protein, rat; D053675:Versicans; D006820:Hyaluronic Acid