Young Hyun Yoo, M.D., Ph.D.
Affiliation: Department of Anatomy and Cell Biology, Mitochondria Hub Regulation Center, Dong-A University College of Medicine, Busan, Korea
Title: Non-lens function of alpha-B-crystallin in retinal pigment epithelial cells pertaining to pathogenesis of aged macular degeneration
In addition to its well-characterized role in the lens, αB-crystallin performs other functions. αB-crystallin on RPE cells may function as an antiapoptotic protein. The prevention of apoptosis in RPE cells by αB-crystallin has significance in two ocular pathologic conditions. Since RPE cells may be lost by apoptosis in age-related macular degeneration (AMD), αB-crystallin may play a role in preventing the onset of AMD. Conversely, αB-crystallin could inhibit the efficacy of therapeutics in inducing apoptosis in epiretinal membranes in proliferative vitreoretinopathy (PVR) patients. In my previous report, I have demonstrated that silencing of αB-crystallin sensitizes ARPE19 cells to SAHA-induced stage I apoptosis, and abolishing the association of αB-crystallin with HDAC1 on SC35 speckles corresponds to the induction of apoptosis. These data provide some information on the nuclear role of αB-crystallin in RPE cells. In my recent study, I have examined the mechanisms underlying the anti-apoptotic activity of αB-crystallin in the human retinal pigment epithelial cell line ARPE-19 following methylglyoxal MGO treatment since MGO can alter the function of the basement membrane of retinal pigment epithelial (RPE) cells. I observed that αB-crystallin protects ARPE-19 cells from MGO-induced apoptosis. Further, I observed that αB-crystallin interacts with the caspase subtypes, caspase-2L, -2S, -3, -4, -7, -8, -9 and -12 in untreated control ARPE-19 cells and that MGO treatment caused the dissociation of these caspase subtypes from αB-crystallin. Combining our findings that αB-crystallin expressed in glioma cells incapacitates the anti-apoptotic activity exerted by XIAP, αB-crystallin seems to overrides a major antiapoptotic factor XIAP. To this end, I am going to present the data supporting that αB-crystallin protects polyploid retinal pigment cells against autophagy inhibition induced death.
1983: M.D. Pusan National University
1989: Ph.D. Pusan National University(Anatomy)
2009~: Director, Mitochondria Hub Regulation Center
2003~2009: Director, Dong-A University Medical Science Research Center
2001~: Professor, Dong-A University
2010: Regular Member, National Academy of Medicine of Korea
2007: Busan Science and Technology award