Transcriptomic Profiling of Lathyrus sativus L. Metabolism of β-ODAP, a Neuroexcitatory Amino Acid Associated with Neurodegenerative Lower Limb Paralysis

Abstract

Grass pea (Lathyrus sativus L.) is a unique potential crop for marginal arid regions with untapped, exceptional biotic/abiotic stress tolerance, and high protein content seeds. High dietary intake of grass pea is associated with neurodegenerative lower limb paralysis, thought due to the compound β-N-oxalyl-L-α, β-diaminopropionic acid (β-ODAP). β-ODAP increases after seed germination and then decreases subsequently. To monitor changes in gene expression during seed germination, RNA sequencing was performed on seedlings at 2, 6, and 25 days after sowing. A total of 213,258 unigenes were detected, corresponding to 39,548 coding sequences. Extensive Gene Ontology and coexpression network analysis suggested that primary metabolism, particularly carbohydrates and sulfur, were correlated with β-ODAP content. Our results identified transcriptional profiles related to grass pea seedling development, and provide invaluable insight into mechanisms of β-ODAP accumulation and degradation. Defining the gene space is essential for intelligent genetic, biotechnological, and breeding efforts to reduce β-ODAP for human benefit.