Abstract: Perilla ［Perilla frutescens (L.) Britt.］ is a new type of edible-medicinal oil crop. The transcription factor WRI1 (WRINKLED1) is master regulator in transcriptional control of plant oil biosynthesis and accumulation. To explore the molecular mechanism of PfWRI1 transcription factor in regulating oil synthesis accumulation and stress response in perilla, PfWRI1 transcription factor was cloned from perilla by molecular cloning technique. The sequence characteristics and expression levels were analyzed using bioinformatics analysis tools and semi-quantitative reverse transcription polymerase chain reaction (sqRT-PCR) and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) techniques. The results showed that PfWRI1 transcription factor is a member of the AP2 (APETALA2) transcription factor family, which contains two AP2 conserved domains and is localized at the nucleus. Random coil and α-helix were the main structural elements in the secondary structure of PfWRI1 protein. Phylogenetic analysis showed that the closest relatives to PfWRI1 are Sesamum indicum and Persea americana WRI1. The prediction of interacting proteins indicated that PfWRI1 protein might interact with LEC1 (LEAFYCOTYLEDON1), FATA (fatty acyl-acyl carrier protien thioesterase), FATB and PDAT (phospholipids: diacylglycerol acyltransferase). PfWRI1 expressed in all perilla organs/tissues tested, whereas their expression levels were different in these tissues. The expression level of PfWRI1 increased in the early developmental stage and then decreased, and which reached the peak l in seed at 30 days after flowering (DAF) with the seed maturity. It was suggested that PfWRI1 may play an important regulatory role in perilla seed oil synthesis. The expression of PfWRI1 transcription factor peaked after 12 hours under low temperature stress of perilla seedlings, indicating that PfWRI1 may be involved in the response to cold stress. This study lays a foundation for further research on the molecular mechanism and function of PfWRI1 in oil synthesis and accumulation and stress response of perilla, and provides a theoretical basis for genetic improvement and new variety breeding of perilla and other oil crops.
Key words: perilla ［Perilla frutescens (L.) Britt］; WRI1 transcription factor; sequence characterization analysis; expression analysis; low temperature stress response
（Acta Laser Biology Sinica, 2022, 31(5): 450-460）