RSC Publishing


Publishing

 

Cover image for Photochemical & Photobiological Sciences, select for current issue

Photochemical & Photobiological Sciences

A society-owned journal publishing high quality research on all aspects of photochemistry and photobiology.



Subscribers

Non-subscribers

Free access



Paper

Photochem. Photobiol. Sci., 2008, 7, 1041 - 1045, DOI: 10.1039/b717280j


A rhodopsin immunoanalog in the related photosensitive protozoans Blepharisma japonicum and Stentor coeruleus

Hanna Fabczak, Katarzyna Sobierajska and Stanisaw Fabczak


Immunoblotting of isolated cell membrane fractions from ciliates Blepharisma japonicum and Stentor coeruleus with a polyclonal antibody raised against rhodopsin revealed one strong protein band of about 36 kDa, thought to correspond to protozoan rhodopsin. Inspection of both ciliates labeled with the same antibody using a confocal microscope confirmed the immunoblotting result and demonstrated the presence of these rhodopsin-like molecules localized within the cell membrane area. Immunoblot analysis of the ciliate membrane fractions resolved by two-dimensional gel electrophoresis identified two distinct 36 kDa spots at pIs of 4.5 and 7.0 for Blepharisma, and three spots at pIs of 4.4, 5.0 and 6.0 for Stentor, indicating a possible mixture of phosphorylated rhodopsin species in these cells. The obtained results suggest that both Blepharisma and the related ciliate Stentor contain within the cell membrane the rhodopsin-like proteins, which may be involved as receptor molecules in the sensory transduction pathway mediating motile photoresponses in these protists as in other species of lower eukaryota.

Graphical abstract image for this article  (ID: b717280j)