Convergent evolution of tertiary structure in rhodopsin visual proteins from vertebrates and box jellyfish.

ABSTRACT: Box jellyfish and vertebrates are separated by >500 million years of evolution yet have structurally analogous lens eyes that employ rhodopsin photopigments for vision. All opsins possess a negatively charged residue-the counterion-to maintain visible-light sensitivity and facilitate photoisomerization of their retinaldehyde chromophore. In vertebrate rhodopsins, the molecular evolution of the counterion position-from a highly conserved distal location in the second extracellular loop (E181) to a proximal location in the third transmembrane helix (E113)-is established as a key driver of higher fidelity photoreception. Here, we use computational biology and heterologous action spectroscopy to determine whether the appearance of the advanced visual apparatus in box jellyfish was also accompa

SUBMITTER: Gerrard E 

PROVIDER: S-EPMC6004467 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature