Abstract
Purpose :
The mouse genome contains four centrin genes (Cetn1-4), which encode four conserved basal body (bb)/cilium-associated calcium-binding protein centrins. We have previously generated Cetn1 and Cetn2 knockout (KO) with no detectable retina phenotype (Avasthi et al., 2013) (Ying et al., 2014). This study continues to examine the role of Cetn 2 and Cetn3 in mouse photoreceptor development and maintenance.
Methods :
We generated a Cetn3 knockout (KO) mouse using Eucomm ES cell lines and subsequently Cetn2 and 3 double kockout (dKO) mice by crossing Cetn3 KO with Cetn2 KO. Electroretinography (ERG) was used to assess the function of mutant retina, and immunostaining was used to check the ciliary trafficking of rhodopsin and other major outer segment (OS) phototransduction proteins.
Results :
Cetn3 KO mouse has normal ERG and retinal morphology up to 10 month old, and rhodopsin and other major outer segment (OS) phototransduction proteins traffic correctly. However, Cetn2/Cetn3 dKO mouse has severely reduced ERG, shortened photoreceptor OS, and thinned outer nuclear layer (ONL). Rhodopsin and other OS proteins traffic normally to the outer segments at 3 month of age.
Conclusions :
Cetn2 deletion is associated with dysosmia and trafficking in mouse olfactory neurons. Cetn2 and Cetn3 single knockouts have no recognizable retina phenotype suggesting that Cetn2 and Cetn3 are redundant in retina. However, both Cetn2 and Cetn3 are required for photoreceptor survival.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.