Yu Kunjiang, Wang Xiaodong, Chen Feng, Peng Qi, Chen Song, Li Hongge, Zhang Wei, Fu Sanxiong, Hu Maolong, Long Weihua, Chu Pu, Guan Rongzhan, Zhang Jiefu
Key Laboratory of Cotton and Rapeseed, Ministry of Agriculture, Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences, Nanjing, China.
State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, China.
Front Plant Sci. 2018 Feb 1;9:89. doi: 10.3389/fpls.2018.00089. eCollection 2018.
The apetalous trait of rapeseed (, AACC, 2 = 38) is important for breeding an ideal high-yield rapeseed with superior klendusity to . Currently, the molecular mechanism underlying the apetalous trait of rapeseed is unclear. In this study, 14 petal regulators genes were chosen as target genes (TGs), and the expression patterns of the 14 TGs in the AH population, containing 189 recombinant inbred lines derived from a cross between apetalous "APL01" and normal "Holly," were analyzed in two environments using qRT-PCR. Phenotypic data of petalous degree (PDgr) in the AH population were obtained from the two environments. Both quantitative trait transcript (QTT)-association mapping and expression QTL (eQTL) analyses of TGs expression levels were performed to reveal regulatory relationships among TGs and PDgr. QTT mapping for PDgr determined that () was the major negative QTT associated with PDgr in both environments, suggesting that negatively regulates the petal development of line "APL01." The QTT mapping of expression levels showed that () was positively associated with expression, indicating that acts as a positive regulator of expression. Similarly, QTT mapping for the remaining TGs identified 38 QTTs, associated with 13 TGs, and 31 QTTs, associated with 10 TGs, respectively, in the first and second environments. Additionally, eQTL analyses of TG expression levels showed that 12 and 11 unconditional eQTLs were detected in the first and second environment, respectively. Based on the QTTs and unconditional eQTLs detected, we presented a hypothetical molecular regulatory network in which 14 petal regulators potentially regulated the apetalous trait in "APL01" through the pathway. acts directly as the terminal signal integrator negatively regulating petal development in the pathway. These findings will aid in the understanding the molecular mechanism underlying the apetalous trait of rapeseed.
油菜（，AACC，2n = 38）的无花瓣性状对于培育具有比[对照品种]更优紧凑度的理想高产油菜十分重要。目前，油菜无花瓣性状的分子机制尚不清楚。在本研究中，选择了14个花瓣调控基因作为目标基因（TGs），利用qRT-PCR在两种环境下分析了这14个TGs在AH群体中的表达模式，该群体包含189个重组自交系，由无花瓣的“APL01”与正常的“Holly”杂交获得。从这两种环境中获取了AH群体花瓣度（PDgr）的表型数据。对TGs表达水平进行了数量性状转录本（QTT）关联作图和表达QTL（eQTL）分析，以揭示TGs与PDgr之间的调控关系。PDgr的QTT作图确定[基因名称1]在两种环境下均为与PDgr相关的主要负向QTT，表明[基因名称1]对“APL01”品系的花瓣发育起负调控作用。[基因名称1]表达水平的QTT作图显示[基因名称2]与[基因名称1]的表达呈正相关，表明[基因名称2]作为[基因名称1]表达的正向调控因子。同样，对其余TGs的QTT作图在第一和第二种环境中分别鉴定出与13个TGs相关的38个QTT和与10个TGs相关的3l个QTT。此外，TGs表达水平的eQTL分析表明，在第一和第二种环境中分别检测到12个和11个无条件eQTL。基于检测到的QTT和无条件eQTL，我们提出了一个假设的分子调控网络，其中14个花瓣调控因子可能通过[信号通路名称]途径调控“APL01”中的无花瓣性状。[基因名称1]直接作为终端信号整合子，在[信号通路名称]途径中对花瓣发育起负调控作用。这些发现将有助于理解油菜无花瓣性状的分子机制。
