RPE (ribulose-5-phosphate-3-epimerase) is a metabolic enzyme that catalyzes the reversible epimerization of D-ribulose 5-phosphate to D-xylulose 5-phosphate, functioning as a homodimer in the pentose-phosphate shunt's non-oxidative branch [UniProt annotation]. The enzyme operates in the cytosol and extracellular exosomes, binding metal ions and identical protein partners to facilitate carbohydrate metabolism. However, the provided abstracts do not directly address the biochemical function or disease relevance of the RPE gene itself. Instead, the abstracts focus on retinal pigment epithelium (RPE) cells—a distinct tissue type in the eye. These cell studies demonstrate that healthy RPE cells exhibit metabolic flexibility, utilizing 48-51 nutrients including sugars, TCA cycle intermediates, and amino acids 1. RPE dysfunction underlies retinal degenerative diseases including age-related macular degeneration and bestrophinopathies, characterized by abnormal autofluorescent accumulation and impaired photoreceptor support 2. Clinical applications of stem cell-derived RPE transplantation have shown promise for treating retinal degeneration without observed tumorigenicity, though immunological rejection remains a consideration for allogeneic grafts 3. Ion channel defects in RPE cells are associated with retinopathies causing blindness 4. Direct information about ribulose-5-phosphate-3-epimerase's role in disease or clinical significance is absent from the provided abstracts.