Deep-sea fish reveal an alternative developmental trajectory for vertebrate vision.

ABSTRACT: Vertebrate vision relies on two photoreceptor types: cones for bright light and rods for dim light. The current dogma is that vertebrates develop cone-dominated retinas first, adding rods later. Here we show that larval deep-sea fishes have "hybrid" photoreceptors, expressing cone-specific genes in rod-like cells. Through development, they either retain these rod-like cones (in Maurolicus mucronatus) or transition to true rods expressing rod-specific genes and transcription factors (in Vinciguerria mabahiss and Benthosema pterotum). Unlike most marine fish larvae, which inhabit brightly lit waters, deep-sea fish larvae experience deeper and dimmer environments. By combining rod-like morphology with cone-like molecular machinery, hybrid photoreceptors likely maximize vi

SUBMITTER: Fogg LG 

PROVIDER: S-EPMC12893277 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature