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. 2013 Apr 23;4(5):364–372. doi: 10.1007/s13238-013-3015-z

C13C4.5/Spinster, an evolutionarily conserved protein that regulates fertility in C. elegans through a lysosome-mediated lipid metabolism process

Mei Han 13015,23015, Hao Chang 13015,33015, Peng Zhang 13015,23015, Tao Chen 43015, Yanhua Zhao 13015, Yongdeng Zhang 13015, Pingsheng Liu 13015, Tao Xu 13015,✉, Pingyong Xu 53015,✉
PMCID: PMC4875547  PMID: 23609012

Abstract

Lipid droplets, which are conserved across almost all species, are cytoplasmic organelles used to store neutral lipids. Identification of lipid droplet regulators will be conducive to resolving obesity and other fat-associated diseases. In this paper, we selected 11 candidates that might be associated with lipid metabolism in Caenorhabditis elegans. Using a BODIPY 493/503-based flow cytometry screen, 6 negative and 3 positive regulators of fat content were identified. We selected one negative regulator of lipid content, C13C4.5, for future study. C13C4.5 was mainly expressed in the worm intestine. We found that this gene was important for maintaining the metabolism of lipid droplets. Biochemical results revealed that 50% of triacylglycerol (TAG) was lost in C13C4.5 knockout worms. Stimulated Raman scattering (SRS) signals in C13C4.5 mutants showed only 49.6% of the fat content in the proximal intestinal region and 86.3% in the distal intestinal region compared with wild type animals. The mean values of lipid droplet size and intensity in C13C4.5 knockout animals were found to be significantly decreased compared with those in wild type worms. The LMP-1-labeled membrane structures in worm intestines were also enlarged in C13C4.5 mutant animals. Finally, fertility defects were found in C13C4.5(ok2087) mutants. Taken together, these results indicate that C13C4.5 may regulate the fertility of C. elegans by changing the size and fat content of lipid droplets by interfering with lysosomal morphology and function.

Electronic Supplementary Material

Supplementary material is available for this article at 10.1007/s13238-013-3015-z and is accessible for authorized users.

Keywords: C13C4.5, Spinster, lipid droplet, SRS microscopy, lysosomal enlargement, fertility

Electronic supplementary material

13238_2013_3015_MOESM1_ESM.pdf (333.7KB, pdf)

Supplementary material, approximately 333 KB.

Footnotes

Electronic Supplementary Material

Supplementary material is available for this article at 10.1007/s13238-013-3015-z and is accessible for authorized users.

Contributor Information

Tao Xu, Email: xutao@ibp.ac.cn.

Pingyong Xu, Email: pyxu@ibp.ac.cn.

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13238_2013_3015_MOESM1_ESM.pdf (333.7KB, pdf)

Supplementary material, approximately 333 KB.

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