Cao Huifen, Zhang Xiao, Li Feng, Han Zhiping, Ding Baopeng
Key Laboratory of Organic Dry Farming for Special Crops in Datong City, College of Agriculture and Life Science, Shanxi Datong University, Datong, 037009 Shanxi Province China.
Engineering Research Center of Coal-based Ecological Carbon Sequestration Technology of the Ministry of Education, Key Laboratory of National Forest and Grass Administration for the Application of Graphene in Forestry, Shanxi Datong University, Datong, 037009 Shanxi Province China.
Physiol Mol Biol Plants. 2024 Aug;30(8):1253-1263. doi: 10.1007/s12298-024-01493-y. Epub 2024 Jul 24.
Callus formation induced by auxin accumulation is considered the first step of in vitro plant regeneration. In , degradation of the Aux/IAA protein, IAA14, in response to auxin signaling, which activates the AUXIN RESPONSE FACTOR 7 (ARF7) and ARF19 along with a series of downstream transcription factors, also plays a critical role in this process. However, the specific mechanism by which auxin regulates callus formation remains unclear. By screening mutant library in the ( background we obtained the () mutant. The mutant exhibited a stronger capacity for callus formation, as well as lateral root and adventitious root regeneration from leaf explants than wild type (WT) seedlings, but did not recover gravitropism capability. The auxin signal in was significantly enhanced, and the expression of some downstream transcription factors was increased. Map-based cloning, whole genome resequencing, and phenotypic complementation experiments showed that the phenotypes observed in the mutant were caused by a point mutation in the promoter region. This mutation, which is predicted to disrupt the binding of LBD16, LBD19, and LBD30 to the promoter, changed the expression pattern of IAA14 in . Taken together, our results identified a new mutation in the promoter region, which affects the expression pattern of and in turn its ability to control plant regeneration.
The online version contains supplementary material available at 10.1007/s12298-024-01493-y.
生长素积累诱导的愈伤组织形成被认为是体外植物再生的第一步。在[具体植物名称未给出]中，Aux/IAA蛋白IAA14响应生长素信号而降解，这激活了生长素响应因子7（ARF7）和ARF19以及一系列下游转录因子，在这个过程中也起着关键作用。然而，生长素调节愈伤组织形成的具体机制仍不清楚。通过在[具体植物名称未给出]（[具体植物名称未给出]背景）中筛选突变体文库，我们获得了[具体植物名称未给出]（[具体植物名称未给出]）突变体。与野生型（WT）幼苗相比，[具体植物名称未给出]突变体表现出更强的愈伤组织形成能力，以及从叶片外植体再生侧根和不定根的能力，但没有恢复向重力性能力。[具体植物名称未给出]中的生长素信号显著增强，一些下游转录因子的表达增加。基于图位克隆、全基因组重测序和表型互补实验表明，在[具体植物名称未给出]突变体中观察到的表型是由[具体植物名称未给出]启动子区域的一个点突变引起的。这个突变预计会破坏LBD16、LBD19和LBD30与[具体植物名称未给出]启动子的结合，改变[具体植物名称未给出]中IAA14的表达模式。综上所述，我们的结果在[具体植物名称未给出]启动子区域鉴定出一个新突变，它影响[具体植物名称未给出]的表达模式，进而影响其控制植物再生的能力。
在线版本包含可在10.1007/s12298-024-01493-y获取的补充材料。
