Understanding the birth of photoreceptors In 2001, Swaroop's team first showed that the gene NRL, discovered several years earlier in his U-M lab, is essential for the development of rods. In its absence, all rods were converted to cones.
Earlier this year, Drs. Masayuki Akimoto and Hong Cheng in the Swaroop lab published an important study describing the "birth" of rod cells.* They were able to make this process visible by building on previous research, using an NRL gene regulatory element to tag the rods with a green fluorescent protein. This enabled Kellogg scientists to illuminate the rods, which begin as unspecified cells and gradually differentiate into cells dedicated to light reception. "One of our critical discoveries," says Swaroop, "is that there is a window of opportunity during which a cell has committed itself to becoming a rod but has not yet started to function as such."
The collaboration with Ali's group, funded by the UK's Medical Research Council in London, was critical in testing the next phase of the research. The goal was to learn whether transplanting cells isolated at a specific time period would significantly increase the chances that "precursor" cells would develop into functioning rods and integrate in the retinal milieu.
The new paper shows that successful transplantation requires that cells reach a certain level of maturity before being transplanted into the eye. When the cells were transplanted at a very early stage, bef
Source:University of Michigan Health System