Someday they’ll find it–the Rainbow Connection!
This is Sandra Tsing Loh with the Loh Down on Science.
Animals are kinda color-blind. Only some can tell between MEDIUM green wavelengths and LONG red wavelengths. And the different cells that sense color are tough to distinguish!
Sarah Hadyniak and Johns Hopkins University wanted to know more. They grew organoids, groups of cells that mimic an organ. In this case: the eye! Then, they added retinoic acid–made naturally from Vitamin A–at different stages of development. Without it, an organoid will make both medium and long wavelength-sensing cells.
Results?
Adding retinoic acid early made medium wavelength, or green-sensing cells. Adding it later made long wavelength, or red-sensing cells! This could help us understand what makes primates unique from other mammals!
And the lovers, the dreamers, and me.
Reference: Hadyniak, S. E., Joanna, Eldred, K. C., Brenerman, B., Hussey, K. A., McCoy, R. C., Michael, Kuchenbecker, J. A., Reh, T., Glass, I., Neitz, M., Neitz, J., Taylor, J., & Johnston, R. J. (2024). Retinoic acid signaling regulates spatiotemporal specification of human green and red cones. PLOS Biology, 22(1), e3002464–e3002464. https://doi.org/10.1371/journal.pbio.3002464