ANALYSIS OF DIFFERENTIALLY EXPRESSED GENES IN RETINITIS-PIGMENTOSA RETINAS - ALTERED EXPRESSION OF CLUSTERING MESSENGER-RNA

The molecular and cellular processes underlying photoreceptor degeneration in retinitis pigmentosa (RP) are unknown. We have investigated gene expression in diseased retinas using differential hybridization screening of a retinal cDNA library with probes derived from normal and RP retinal RNA. Most differential clones detected corresponded to transcripts absent from the dystrophic state, including e.g. opsin. However, one clone was noticeably increased in RP in comparison with the control: partial sequencing showed it encoded clusterin. Increased expression of clusterin has been identified in several cases of tissues undergoing apoptosis (programmed cell death), and our finding suggests that the degenerative changes in advanced RP may represent another example of apoptosis, possibly with common causative mechanisms.