LOCAL SYNTHESIS OF APOLIPOPROTEIN-J IN THE EYE

Apolipoprotein J (apoJ), a secretory glycoprotein known to transport l ipids and to regulate terminal complement function, is present in the human eye in both aqueous and vitreous, as well as in the retina. Ocul ar apoJ is the product of local synthesis, rather than plasma contamin ation, as demonstrated by its distinct structural properties and the p resence of abundant apoJ mRNA in retina and retina pigment epithelium. ApoJ mRNA is also present in mouse eye, with a developmentally regula ted pattern of expression. In fetal mouse, apoJ mRNA is present in ret ina, lens and cornea. In contrast, adult eye apoJ mRNA is present in r etina and ciliary body. We propose that apoJ is important in tissue re modeling and in stabilizing hydrophobic molecules which are required f or vision and/or which would otherwise be deleterious and membrane-act ive.