Characteristic expression patterns of PROX1, GLAST, GFAP, and PLP1 in the cochlea of the common marmoset

Supporting cells within the cochlea are integral to auditory function, and their gene expression patterns have been extensively characterized in rodent models. However, the characteristics of cochlear supporting cells in primates remain less comprehensively understood. The marker genes Prox1, Slc1a3 (GLAST), Gfap, and Plp1 are commonly employed to identify supporting cell subtypes, and their specific promoter activity is used to manipulate gene expression patterns in murine supporting cells. In this study, we employed the common marmoset as a primate model to investigate the developmental expression of PROX1, SLC1A3 (GLAST), GFAP, and PLP1 in the primate cochlea. The expression patterns of PROX1 and GLAST are largely conserved between rodents and primates, localizing to specific supporting cells during development. In contrast, GFAP and PLP1 exhibited distinct expression patterns in primate-supporting cells compared to those observed in rodents; specifically, GFAP expression was more limited, and PLP1 expression was absent in common marmosets. These findings reveal interspecies differences in the gene expression of cochlear supporting cells, suggesting that gene manipulation techniques developed in rodent models may not be directly applicable to primates. Our results highlight the need for primate-specific genetic tools to enhance understanding of cochlear biology and facilitate the development of targeted therapies for human hearing loss.