Diacylglycerol kinase epsilon presence in bovine rod outer segments

ZULIAN SE; ILINCHETA DE BOSCHERO MG; GIUSTO NM

Huerta Grande, Córdoba, Argentina

Congreso; I Joint Meeting of the Argentine Society for Neurosciences (SAN), Huerta Grande, Córdoba, 4-6/09/2009. P162 sección III. pág. 234.; 2009

Sociedad Argentina de Neurociencias

Vertebrate retinal photoreceptor cells have an active phosphoinositide metabolism and several steps in the PI cycle are stimulated by light. We have been reported in bovine ROS, a peripherally associated DAGK that change their association to membrane in response to light. A DAGK activity, up-regulated by transducin subunits dissociation was also proposed on the basis of GTPgS and fluoride action. In ROS obtained from bleached bovine retina (B-ROS) a DAGK g isozyme, was reported to be photoassociated and activated by light. At present, DAGKe and DAGKg presence in ROS obtained from dark bovine retina (D-ROS), B-ROS and D-ROS exposed to brief light (ROS-L) were evaluated by immunofluorescense microscopy (IM) and western blot. Rabbit polyclonal DAGK antibodies (anti-DAGKe or anti-DAGKg) and goat anti-rabbit secondary antibody coupled to FITC was employed to isoforms detection by IM. Interestingly, positive DAGKe labeling was founded into ROS with a particulate distribution and membrane localization is suggested. Positive ROS-DAGKg labeling homogenously distributed was founded and soluble localization is confirmed. DAGKe predominantly phosphorylates DAG with an arachidonate in sn2 position, thus giving support to the notion that in ROS DAGKe could plays a role than in enriching inositol phospholipids synthesis.