*3.5. Other Metabolism*

In our previous study [5], GC-MS lipid profiling was performed on non-polar extracts of rice leaves from WT and M. Three classes of lipid were analyzed, i.e., plant glycolipids, the common membrane phospholipid classes, and the minor membrane lipid metabolites. Compared with WT, there were no significant alteration in total monogalactosyldiacylglycerol (MGDG) or total digalactosyldiacylglycerol (DGDG), but significant increase of MGDG 34:6, and significant decreases of DGDG 34:1, DGDG 36:2, total phosphatidylglycerol (PG), PG 36:2, total lysoPG and lysoPG 16:1 in M. While, in the present study, untargeted NMR metabolic profiling was performed on the polar extraction of the whole 2-week-old seedling shoots without roots. The accumulation of total lipids, with a wider species coverage than our previous study [5], was observed in both M and ECE. Though the difference in plant material, extraction method, and lipid coverage may lead to different results, both studies suggested that *OsCYP96B4* might be involved in rice plant lipid metabolism. The accumulation of lipids observed here may indicate the reduced conversion of lipids to other metabolites or the increased synthesis of lipids from other metabolites. The significant elevation of N-methylnicotinate level in both M and ECE may indicate the potential effect of this mutation on vitamin B3 metabolism. In addition, the significant increase of formate concentration suggests altered formate metabolism in ECE.

### **4. Materials and Methods**
