By Wang Guifeng
Researchers of Group of Seed Biology from Henan Agricultural University reported a novel maize (Zea mays L.) opaque mutant o18, which displays an increase in lysine accumulation but impaired endosperm filling and embryo development. O18 encodes a rate-limiting bifunctional enzyme ZmRIBA1, targeted to plastid where to initiate riboflavin biosynthesis. Loss of function of O18 specifically disrupts respiratory complexes I and II, but also decreases SDH1 flavinylation, and in turn shifts the tricarboxylic acid cycle to glycolysis. The deprivation of cellular energy leads to G1/S arrest of endosperm cells, in both mitotic and endoreduplicaing cycles. The unexpected upregulation of cell cycle genes in o18 correlates with the increase of H3K4me3 levels, revealing a possible H3K4me-mediated epigenetic backup mechanism for cell cycle progression under unfavorable circumstances. Overexpression of O18 increases riboflavin production and confers osmotic tolerance. Altogether, the results substantiate a key role of riboflavin in coordinating cellular energy and cell cycle to modulate maize endosperm development.
The article has recently been published in a peer-reviewed journal, 《Plant Biotechnology Journal》(IF=9.803, 2021), entitled “Riboflavin integrates cellular energetics and cell cycle to regulate maize seed development”.
The PhD candidate Ms. Qiuzhen Tian is the first author, and Prof. Guifeng Wang is the corresponding author, as well as the collaboration with Prof. Jihua Tang, Prof. Qinghua Yang and Prof. Zhiyuan Fu. This research was jointly supported by grants from the National Natural Sciences Foundation of China and the National Key R&D Program.
Edited by Chen Xi
Authorized by Wang Hongyan, Zhou Hongfei
