Björn J. Öbrink (1943-2015).

Family members, friends and colleagues of Prof. Dr. Dr. h.c. Björn Öbrink were deeply saddened to learn of his sudden death on August 21, 2015. Björn was one of the pioneers in cell adhesion research. Reading an article written by Björn, one quickly recognizes his outstanding qualities as a scientist: knowledgeable, innovative, precise and detailed in order to enable reproduction of his reported results. When meeting Björn, you were captured by his personality: warm-hearted, modest, and, above all, devoted to truth.

Fifty years later: the disk goes to the prom.

Although age-related macular degeneration is the most prevalent macular disease in the world, numerous discoveries regarding the molecular bases of vision have been made through genetic association studies of rare inherited maculopathies. In this issue of the JCI, Yang et al. present a functional genetics study that identifies a role for prominin 1 (PROM1), best known as a stem cell and/or progenitor cell marker, in the biogenesis of retinal photoreceptor disk arrays (see the related article beginning on page 2908). This study supports an established model in which disk morphogenesis occurs through membrane evagination and extends other recent studies assigning PROM1 important functions outside of the stem cell niche.