Nervonic acid is a rare fatty acid essential for brain health and for the treatment of neurodegenerative diseases. However, traditional sources derived from animals are limited. While plant seed oils serve as the primary natural source, most nervonic acid-rich plants remain wild and undomesticated. There is an urgent need to understand the underlying mechanisms that could enable large-scale production through artificial cultivation.
In a study published in Horticulture Research, researchers from Xishuangbanna Tropical Botanical Garden (XTBG)of the Chinese Academy of Sciences and their collaborators have assembled the first chromosome-level genomes of two sympatric Macaranga species: Macaranga indica and Macaranga denticulata. Using multi-omics analysis, population genetics, phylogenomics, and molecular validation, the researchers revealed the molecular mechanisms underlying nervonic acid accumulation in Macaranga indica.
Employing advanced single-molecule real-time sequencing and Hi-C scaffolding, the researchers successfully assembled high-quality genomes for both species. Although both genomes are rich in repetitive sequences, Macaranga indica has streamlined its genetic toolkit for fatty acid biosynthesis and accumulation.
The high-nervonic-acid species uses fewer but more highly expressed genes involved in two critical processes for nervonic acid production: fatty acid elongation and triacylglycerol (TAG) synthesis. Additionally, it possesses a single, tightly regulated gene expression module linked to nervonic acid accumulation.
In contrast, the low-nervonic-acid species retains more redundant and diverse gene copies, distributing its metabolic efforts across multiple pathways. This results in a broader but less focused lipid profile.
Cold temperatures, abscisic acid (ABA), and phosphate starvation were identified as major inducers of nervonic acid biosynthesis in Macaranga indica, pointing to specific environmental cues and stress responses that could be leveraged to boost production.
Phylogenetic analysis revealed that nervonic acid biosynthesis evolved convergently in Macaranga indica and other nervonic acid-producing plants. Notably, Macaranga indica has undergone fewer gene duplications and retained a more direct route for nervonic acid production, while Macaranga denticulata has expanded its genetic repertoire to adapt to a wider geographic range.
“Our findings reveal how genomic simplification and targeted environmental responses enable high NA accumulation in Macaranga indica,” said TIAN Bo of XTBG. “This provides a roadmap for domestication and genetic improvement of Macaranga species for industrial-scale nervonic acid production.”
Macaranga indica (Image by TIAN Bo)
Published: 02 April 2026
