Dataset Information

Elovl4a participates in LC-PUFA biosynthesis and is regulated by PPAR?? in golden pompano Trachinotus ovatus (Linnaeus 1758).

ABSTRACT: The elongases of very long-chain fatty acids (Elovls) are responsible for the rate-limiting elongation process in long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis. The transcription factor, PPAR?, regulates lipid metabolism in mammals; however, the detailed mechanism whereby PPAR?b regulates Elovls remains largely unknown in fish. In the present study, we report the full length cDNA sequence of Trachinotus ovatus Elovl4a (ToElovl4a), which encodes a 320 amino acid polypeptide that possesses five putative membrane-spanning domains, a conserved HXXHH histidine motif and an ER retrieval signal. Phylogenetic analysis revealed that the deduced protein of ToElovl4a is highly conserved with the Oreochromis niloticus corresponding homologue. Moreover, functional characterization by heterologous expression in yeast indicated that ToElovl4a can elongate C18 up to C20 polyunsaturated fatty acids. A nutritional study showed that the protein expressions of ToElovl4a in the brain and liver were not significantly affected among the different treatments. The region from PGL3-basic-Elovl4a-5 (-148 bp to +258?bp) is defined as the core promoter via a progressive deletion mutation of ToElovl4a. The results from promoter activity assays suggest that ToElovl4a transcription is positively regulated by PPAR?b. Mutation analyses indicated that the M2 binding site of PPAR?b is functionally important for protein binding, and transcriptional activity of the ToElovl4a promoter significantly decreased after targeted mutation. Furthermore, PPAR?b RNA interference reduced ToPPAR?b and ToElovl4a expression at the protein levels in a time-dependent manner. In summary, PPAR?b may promote the biosynthesis of LC-PUFA by regulating ToElovl4a expression in fish.

SUBMITTER: Zhu KC

PROVIDER: S-EPMC6423087 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Elovl4a participates in LC-PUFA biosynthesis and is regulated by PPARαβ in golden pompano Trachinotus ovatus (Linnaeus 1758).

Zhu Ke-Cheng KC Song Ling L Guo Hua-Yang HY Guo Liang L Zhang Nan N Liu Bao-Suo BS Jiang Shi-Gui SG Zhang Dian-Chang DC

Scientific reports 20190318 1

The elongases of very long-chain fatty acids (Elovls) are responsible for the rate-limiting elongation process in long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis. The transcription factor, PPARα, regulates lipid metabolism in mammals; however, the detailed mechanism whereby PPARαb regulates Elovls remains largely unknown in fish. In the present study, we report the full length cDNA sequence of Trachinotus ovatus Elovl4a (ToElovl4a), which encodes a 320 amino acid polypeptide that po ...[more]

PMID: 30886313

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Dataset Information

Elovl4a participates in LC-PUFA biosynthesis and is regulated by PPAR?? in golden pompano Trachinotus ovatus (Linnaeus 1758).

Publications

Elovl4a participates in LC-PUFA biosynthesis and is regulated by PPARαβ in golden pompano Trachinotus ovatus (Linnaeus 1758).

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