Novel role for alphavbeta5-integrin in retinal adhesion and its diurnal peak |
| |
Authors: | Nandrot Emeline F Anand Monika Sircar Mousumi Finnemann Silvia C |
| |
Institution: | Margaret M. Dyson Vision Research Institute, Department of Ophthalmology, Weill Medical College of Cornell University, 1300 York Ave., New York, NY 10021, USA. |
| |
Abstract: | v5-Integrin is the sole integrin receptor at the retinal pigment epithelium (RPE)-photoreceptor interface and promotes RPE phagocytic signaling to the tyrosine kinase Mer tyrosine kinase (MerTK) once a day in response to circadian photoreceptor shedding. Herein we identify a novel role for v5-integrin in permanent RPE-photoreceptor adhesion that is independent of v5's function in retinal phagocytosis. To compare retinal adhesion of wild-type and 5-integrin/ mice, we mechanically separated RPE and neural retina and quantified RPE protein and pigment retention with the neural retina. Lack of v5-integrin with normal expression of other RPE integrins greatly weakened retinal adhesion in young mice and accelerated its age-dependent decline. Unexpectedly, the strength of wild-type retinal adhesion varied with a diurnal rhythm that peaked 3.5 h after light onset, after the completion of phagocytosis, when integrin signaling to MerTK is minimal. Permanent v5 receptor deficiency attenuated the diurnal peak of retinal adhesion in 5-integrin/ mice. These results identify v5-integrin as the first RPE receptor that contributes to retinal adhesion, a vital mechanism for long-term photoreceptor function and viability. Furthermore, they indicate that v5 receptors at the same apical plasma membrane domain of RPE cells fulfill two separate functions that are synchronized by different diurnal rhythms. circadian rhythm; knockout; photoreceptors; retinal pigment epithelium |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
| 点击此处可从《American journal of physiology》浏览原始摘要信息 |
| 点击此处可从《American journal of physiology》下载免费的PDF全文 |
|