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Lysophosphatidylcholine acyltransferase 1 controls the mitochondrial reactive oxygen species generation and survival of the retinal photoreceptor cells [P8 photoreceptor]

ABSTRACT: Due to the high energy demands and characteristic morphology, retinal photoreceptor cells require a specialized lipid metabolism for survival and function. This study focused on the roles of saturated fatty acids and their metabolism. A frameshift mutation of lysophosphatidylcholine acyltransferase 1 (Lpcat1), introducing saturated fatty acids into lysophosphatidylcholine to produce disaturated phosphatidylcholine (PC), has been reported to cause spontaneous retinal degeneration in mice (rd11 mice).　In this study, we performed a detailed characterization of Lpcat1 in the retina and found that Lpcat1 deficiency induces light-independent and photoreceptor-specific apoptosis in mice. Lipidomic analyses of the retina and isolated photoreceptor outer segment (OS) suggested that loss of Lpcat1 affects disaturated PC production and the proper cellular fatty acid flux, presumably by altering saturated fatty acyl-CoA availabilities. Furthermore, we demonstrated that Lpcat1 deletion increased mitochondrial reactive oxygen species (ROS) levels in photoreceptor cells, but not in other retinal cells without affecting the OS structure and trafficking of OS-localized proteins. These results suggest that the LPCAT1-dependent production of disaturated PC is critical for metabolic adaptation during photoreceptor maturation. Our findings highlight the therapeutic potential of saturated fatty acid metabolism in photoreceptor cell degeneration-related retinal diseases.

ORGANISM(S): Mus musculus

PROVIDER: GSE184817 | GEO | 2022/01/01

REPOSITORIES: GEO

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Lysophosphatidylcholine acyltransferase 1 controls the mitochondrial reactive oxygen species generation and survival of the retinal photoreceptor cells [2w Retina]

Project description:Due to the high energy demands and characteristic morphology, retinal photoreceptor cells require the specialized lipid metabolism for survival and functions. In this study, we focus on the roles of saturated fatty acids and their metabolism in these processes. Frame-shift mutation of lysophosphatidylcholine acyltransferase 1 (Lpcat1), which introduces saturated fatty acid into lysophosphatidylcholine to produce disaturated phosphatidylcholine (PC), has been reported as a causative for spontaneous retinal degeneration in mice (rd11 mice). However, the molecular basis of retinal degeneration caused by Lpcat1 mutation remains unclear. Here, we report that Lpcat1 deficiency induces light-independent and photoreceptor-specific apoptosis in mice. Lipidomic analyses of retina and isolated photoreceptor outer segment (OS) suggested that loss of Lpcat1 affects not only disaturated PC production, but also the proper cellular fatty acid flux presumably through altering saturated fatty acyl-CoA availabilities. Furthermore, we demonstrated that Lpcat1 deletion increased mitochondrial reactive oxygen species (ROS) levels in photoreceptor cells, but not in other retinal cells, without affecting the OS structure and trafficking of OS localized proteins. These results suggested that LPCAT1-dependent production of disaturated PC is critical for metabolic adaptation during photoreceptor maturation. Our findings highlight the therapeutic potential of saturated fatty acid metabolism in photoreceptor cell degeneration-related retinal diseases.

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