An-2 Encodes a Cytokinin Synthesis Enzyme that Regulates Awn Length and Grain Production in Rice
2015; Elsevier BV; Volume: 8; Issue: 11 Linguagem: Inglês
10.1016/j.molp.2015.08.001
ISSN1674-2052
AutoresBenguo Gu, Taoying Zhou, Jianghong Luo, Hui Liu, Yongchun Wang, Yingying Shangguan, Jingjie Zhu, Yan Li, Tao Sang, Zixuan Wang, Bin Han,
Tópico(s)Rice Cultivation and Yield Improvement
ResumoA wide range of morphological and physiological traits have changed between cultivated rice Oryza sativa and wild rice Oryza rufipogon under domestication. Here, we report cloning of the An-2 gene, encoding the Lonely Guy Like protein 6 (OsLOGL6), which catalyzes the final step of cytokinin synthesis in O. rufipogon. The near-isogenic line harboring a wild allele of An-2 in the genetic background of the awnless indica Guangluai 4 shows that An-2 promotes awn elongation by enhancing cell division, but decreases grain production by reducing grains per panicle and tillers per plant. We reveal that a genetic variation in the An-2 locus has a large impact on reducing awn length and increasing tiller and grain numbers in domesticated rice. Analysis of gene expression patterns suggests that An-1 regulates the formation of awn primordial, and An-2 promotes awn elongation. Nucleotide diversity of the An-2 locus in cultivated rice was found to be significantly reduced compared with that of wild rice, suggesting that the An-2 locus was subjected to artificial selection. We therefore propose that the selection of genetic variation in An-2 was due to reduced awn length and increased grain yield in cultivated rice.
Referência(s)