Location: Natural Products Utilization ResearchTitle: Rice momilactone gene cluster: Transcriptional response to Barnyard grass (Echinochloa crus-galli)
Submitted to: Molecular Biology Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/21/2019
Publication Date: 1/4/2020
Citation: Bajsa Hirschel, J.N., Pan, Z., Duke, S.O. 2020. Rice momilactone gene cluster: Transcriptional response to Barnyard grass (Echinochloa crus-galli). Molecular Biology Reports. 47:1507-1512. https://doi.org/10.1007/s11033-019-05205-8.
Interpretive Summary: Expression of genes involved in diterpene biosynthesis, especially momilactone (MA) and gibberellins (GAs), in rice plants (Oryza sativa L.) in response to barnyard grass (Echinochloa crus-galli) stress was examined. The three analyzed class II diterpene synthases had the highest fold change expression. Transcription patterns of two homologs of momilactone synthases, OsMAS and OsMAS2, suggests their distinct roles in response to presence of barnyard grass.
Technical Abstract: We observed a significantly higher transcription of the analyzed genes in roots than leaves in rice plants growing with co-culture with barnyard grass. However, the highest fold in gene expression change, triggered by the presence of barnyard grass, was mostly in leaf tissue. Two of three analyzed class II diterpene synthases (OsCPS1 and 4) were upregulated in leaves. They are involved in momilactone and gibberellin production, respectively. OsCPS2, the first gene of ent-CDP cyclization leading to phytocassanes and oryzalexin D, E biosynthesis, decreased level in leaves of plants grown with barnyardgrass. These results prompt some questions for future experiments. Does the increase of syn-copalyl diphosphate (product of OsCPS4 enzyme) concentration play a regulatory role and/or does the leaf pool of this compound support root momilactone biosynthesis? It would be worth to analyze if the resistance to pathogens is compromised in rice plants growing next to barnyard grass.