| Abstract Detail
Phytochemistry: From atoms to organisms Busta, Lucas [1], Schmitz, Elizabeth [2], Kosma, Dylan [3], Schnable, James [4], Cahoon, Edgar [2]. A co-opted steroid synthesis gene, maintained in sorghum but not maize, is associated with a divergence in leaf wax chemistry. Virtually all land plants are coated in a cuticle, a waxy polyester that prevents non-stomatal water loss and is important for heat and drought tolerance. Here, we describe a likely genetic basis for a divergence in cuticular wax chemistry between Sorghum bicolor, a drought tolerant crop widely cultivated in hot climates, and its close relative Zea mays (maize). Combining chemical analyses, heterologous expression, and comparative genomics, we reveal that: (i) sorghum and maize leaf waxes are similar at the juvenile stage but, after the juvenile-to-adult transition, sorghum leaf waxes are rich in triterpenoids that are absent from maize, (ii) biosynthesis of the majority of sorghum leaf triterpenoids is mediated by a gene that maize and sorghum both inherited from a common ancestor but that is only functionally maintained in sorghum, and (iii) sorghum leaf triterpenoids accumulate in a spatial pattern that was previously shown to strengthen the cuticle and decrease water loss at high temperatures. These findings uncover the possibility for resurrection of a cuticular triterpenoid-synthesizing gene in maize, which could create a more heat-tolerant water barrier on the plant’s leaf surfaces. They also provide a fundamental understanding of sorghum leaf waxes that will inform efforts to divert surface carbon to intracellular storage for bioenergy and bioproduct innovations. Log in to add this item to your schedule
1 - University of Minnesota Duluth, Chemistry and Biochemistry, 1038 University Dr, Duluth, Minnesota, 55812, United States 2 - University of Nebraska 3 - University of Nevada Reno 4 - University Of Nebraska, The Beadle Center E207, 1701 Vine St, The Beadle Center E207, 1701 Vine St, Lincoln, NE, 68516, United States
Keywords: cuticular wax Drought Tolerance triterpenoids juvenile-to-adult transition.
Presentation Type: Colloquium Presentations Session: C05, Phytochemistry: From Atoms to Organisms Location: / Date: Wednesday, July 21st, 2021 Time: 10:30 AM(EDT) Number: C05002 Abstract ID:90 Candidate for Awards:None |