Progresses in biosynthesis pathway, regulation mechanism and potential application of 2-acetyl-1-pyrroline in fragrant rice

• Published in: Plant physiology and biochemistry Vol. 215; p. 109047
• Main Authors: Huang, Yajing, Huang, Lei, Cheng, Maozhi, Li, Chuanhao, Zhou, Xiaofeng, Ullah, Aman, Sarfraz, Samina, Khatab, Ahmed, Xie, Guosheng
• Format: Journal Article
• Language: English
• Published: France Elsevier Masson SAS 01.10.2024
• Subjects: 2-Acetyl-1-pyrroline; Aroma; Biosynthetic Pathways - genetics; Fragrant rice; Gene Expression Regulation, Plant; Non-enzymatic and enzymatic biosynthesis pathway; Odorants; Oryza - genetics; Oryza - metabolism; Plant Proteins - genetics; Plant Proteins - metabolism; Pyrroles - metabolism; Regulatory mechanism; 2-Acetyl-1-pyrroline; Aroma; Non-enzymatic and enzymatic biosynthesis pathway; Fragrant rice; Regulatory mechanism
• ISSN: 0981-9428; 1873-2690; 1873-2690
• DOI: 10.1016/j.plaphy.2024.109047

The formation of rice aroma is a complex process that is influenced by genetic and environmental factors. More than 500 fragrance compounds have been documented in fragrant rice, among which 2-AP dominates the aroma of rice. This paper introduced the identification of OsBadh2 in the biosynthesis of 2-AP in rice. Then, non-enzymatic and enzymatic pathways of the 2-AP biosynthesis have been comprehensively investigated. In detail, 2-AP biosynthesis-associated enzyme, such as OsBADH2, OsP5CS, OsGAD, OsGAPDH, OsProDH, OsOAT, OsODC and OsDAO, have been summarized, while MG and fatty acids are also implicated in modulating the biosynthesis of 2-AP by providing the acetyl groups. Moreover, extensive collections of traditional fragrant rice varieties have been collated, together with the OsBadh2 haplotypes of 312 fragrant rice germplasm in China. And finally, genetic engineering of OsBadh2 and other genes in the 2-AP biosynthesis to develop fragrant rice are discussed. •OsBADH2 is a key gene for the 2-AP biosynthesis with non-enzymatic and enzymatic pathways in rice.•Glutamate, proline and ornithine provide the pyrrole ring for 2-AP biosynthesis.•The methylglyoxal (MG) and fatty acids provide the acetyl group for 2-AP biosynthesis.•Genetic engineering of OsBADH2 and other associated regulatory genes promote production of the fragrant rice and beyond.