RT Journal Article
SR Electronic
T1 The role of <em>AUX1</em> during lateral root development in the domestication of the model C4 grass <em>Setaria italica</em>
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.05.20.444970
DO 10.1101/2021.05.20.444970
A1 Sha Tang
A1 Mojgan Shahriari
A1 Jishan Xiang
A1 Taras Pasternak
A1 Anna Igolkina
A1 Somayeh Aminizade
A1 Hui Zhi
A1 Yuanzhu Gao
A1 Farshad Roodbarkelari
A1 Yi Sui
A1 Guanqing Jia
A1 Chuanyin Wu
A1 Xugang Li
A1 Georgy Meshcheryakov
A1 Maria Samsonova
A1 Xianmin Diao
A1 Klaus Palme
A1 William Teale
YR 2021
UL http://biorxiv.org/content/early/2021/05/21/2021.05.20.444970.abstract
AB C4 photosynthesis increases the efficiency of carbon fixation by spatially separating high concentrations of molecular oxygen from rubisco. The specialized leaf anatomy required for this separation evolved independently many times. C4 root systems are highly branched, an adaptation thought to support high rates of photosynthesis; however, little is known about the molecular mechanisms that have driven the evolution of C4 root system architecture (RSA). Using a mutant screen in the C4 model plant Setaria italica, we identify siaux1-1 and siaux1-2 as RSA mutants, and use CRISPR/cas9-mediated genome editing and overexpression to confirm the importance of the locus. As AUX1 is not necessary for lateral root emergence in S. viridis, the species from which S. italica was domesticated, we conducted an analysis of auxin responsive elements in the promoters of auxin-responsive gene families in S. italica, and explore the molecular basis of SiAUX1’s role in seedling development using an RNAseq analysis of wild type and siaux1-1 plants. Finally, we use a root coordinate system to compare cell-by-cell meristem structures in siaux1-1 and wild type Setaria plants, observing changes in the distribution of cell volumes in all cell layers and a dependence in the frequency of protophloem and protoxylem strands on siAUX1.Competing Interest StatementThe authors have declared no competing interest.