Expression profiles of P2-receptor isoforms P2Y1 and P2Y2 in the rat lens.
OBJECTIVE
To verify at the molecular level that P2 receptors are expressed in the lens and to determine their expression profiles.


METHODS
The reverse transcription-polymerase chain reaction (RT-PCR) was used to screen rat lens epithelial and fiber cells for the expression of the ionotropic P2X2 receptor and the G-protein-linked receptor isoforms P2Y1 and P2Y2. Northern blot analysis was used to confirm the level of expression of P2Y1 and P2Y2. The profile of P2-receptor isoform expression in the lens was identified using an indirect RT-PCR in situ hybridization procedure on paraffin sections of whole rat eyes.


RESULTS
P2X2-receptor transcripts could not be detected in lens epithelial or fiber cells. P2Y1- and P2Y2-receptor transcripts were detected in lens fiber cells but not in the epithelial cells. Their expression profiles were maximal in the lens cortex and mostly overlapped each other, except that transcripts for the P2Y2-receptor isoform appeared earlier in the not yet fully elongated fiber cells in the lens bow region.


CONCLUSIONS
The molecular data support physiological evidence previously reported by others that P2Y receptors are expressed in the lens and identifies cortical fiber cells as the principal site of expression.
Merriman-Smith
R
R
School of Biological Sciences, University of Auckland, New Zealand.
Tunstall
M
M
Kistler
J
J
Donaldson
P
P
Housley
G
G
Eckert
R
R
D000818:Animals; D015152:Blotting, Northern; D004247:DNA / Q000032:analysis; D017931:DNA Primers / Q000737:chemistry; D015342:DNA Probes / Q000737:chemistry; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D017403:In Situ Hybridization; D007908:Lens, Crystalline / Q000378:metabolism*; D012313:RNA / Q000302:isolation & purification; D051381:Rats; D017208:Rats, Wistar; D018048:Receptors, Purinergic P2 / Q000235:genetics / Q000378:metabolism*; D058472:Receptors, Purinergic P2Y1; D058473:Receptors, Purinergic P2Y2; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; D015342:DNA Probes; C546384:P2ry1 protein, rat; C546387:P2ry2 protein, rat; D018048:Receptors, Purinergic P2; D058472:Receptors, Purinergic P2Y1; D058473:Receptors, Purinergic P2Y2; D012313:RNA; D004247:DNA