Encephalic photoreception and phototactic response in the troglobiont Somalian blind cavefish Phreatichthys andruzzii.

ABSTRACT: Many physiological and behavioural responses to changes in environmental lighting conditions are mediated by extraocular photoreceptors. Here we investigate encephalic photoreception in Phreatichthys andruzzii, a typical cave-dwelling fish showing an extreme phenotype with complete anophthalmy and a reduction in size of associated brain structures. We firstly identified two P. andruzzii photopigments, orthologues of rod opsin and exo-rod opsin. In vitro, both opsins serve as light-absorbing photopigments with λ(max) around 500 nm when reconstituted with an A(1) chromophore. When corrected for the summed absorption from the skin and skull, the spectral sensitivity profiles shifted to longer wavelengths (rod opsin: 521 nm; exo-rod opsin: 520 nm). We next explored the involvement of both opsi

SUBMITTER: Tarttelin EE 

PROVIDER: S-EPMC3404804 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature