Expression pattern of connexins in the corneal and limbal epithelium of a primate.
OBJECTIVE
To detect the expression pattern of connexins in epithelial cells of the central cornea and limbus of the macaque.


METHODS
Total RNA was extracted from the central corneal and limbal epithelia of Macaca fascicularis and processed by reverse transcriptase-polymerase chain reaction with isoform primers to detect the expression of 16 connexin (Cx). Immunofluorescent staining of frozen sections of corneal tissue confirmed and localized connexin proteins expression.


RESULTS
Transcripts encoding 10 Cx isoforms (Cx26, Cx30, Cx30.3, Cx31, Cx31.1, Cx32, Cx43, Cx45, Cx50, and Cx58) were detected by reverse transcriptase-polymerase chain reaction in both central and peripheral corneal epithelium. Six (Cx26, Cx31, Cx32, Cx43, Cx45, and Cx58) were confirmed by laser scanning confocal microscopy. Cx26 was detected throughout the central corneal epithelium and in the mid and superficial layers of the limbal epithelium. Cx43 and Cx45 were localized to the basal and suprabasal epithelial cells. Cx58 was expressed in the superficial epithelium throughout the cornea, whereas Cx31 and Cx32 were mainly expressed in the central corneal epithelium and weakly in the limbal area.


CONCLUSIONS
The complex distribution pattern of the connexins suggests that selected isoforms play important roles in maintaining corneal homeostasis.
Yuan
Xiaoyong
X
Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA.
Chen
Zhuo
Z
Yang
Zhuo
Z
Gao
Junfang
J
Zhang
Aijun
A
Wu
Samuel M
SM
Jacoby
Roy
R
D000818:Animals; D017630:Connexins / Q000235:genetics / Q000378:metabolism*; D003315:Cornea / Q000378:metabolism*; D019573:Epithelium, Corneal / Q000378:metabolism*; D005260:Female; D005455:Fluorescent Antibody Technique / Q000379:methods; D016850:Limbus Corneae / Q000378:metabolism*; D008252:Macaca fascicularis; D008297:Male; D018613:Microscopy, Confocal; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013194:Staining and Labeling; D014018:Tissue Distribution
D017630:Connexins; D012333:RNA, Messenger