热胁迫下miR172对大岩桐花发育调控机理的研究

Gloxinia (Sinningia speciosa) is a popular commercial plant for its attractive and colorful flowers. However, high temperature is a limiting factor for gloxinia floral development and the genetic mechanism of floral development under heat stress in gloxinia and other flowers is largely unknown. MiR172, a floral-related factor, plays pivotal roles in ambient-temperature and aging pathways. Considering different reports about roles of miR172 and AP2 in the promotion of floral transition, it seems to be necessary to investigate whether miR172-mediated AP2 at post-transcriptional level results in changed transcript levels of MADS-box genes under heat stress during floral development of gloxinia. To construct the model of floral development by miR172 under heat stress, we have to elucidate the relationship between miR172, AP2 and MADS-box in flower induction responded to high temperature in gloxinia. Our aim is to establish an applicable floral regulation system that will allow floral development to be tolerant under heat stress depending on the demand for ornamental plants.

大岩桐是以观花为主要目的的重要园艺植物，而高温是影响大岩桐花发育的一个主要限制性因子，因此以大岩桐为材料研究高温胁迫对植物花发育影响的分子机制对花卉育种具有重要意义。MiR172作为成花相关因子在年龄以及温度途径中起重要作用。本研究以miR172介导AP2基因的表达调控为切入点, 探明高温条件下大岩桐成花过程中miR172能否在转录后水平迅速地调节AP2靶基因的表达，进而调控下游MADS-box同源基因的表达水平，最终抵抗高温胁迫对大岩桐成花的影响；揭示高温条件下miR172、AP2、MADS-box同源基因表达水平与大岩桐花发育的相关性，建立高温胁迫下miR172介导的AP2转录因子表达调控大岩桐花发育的模型，为花卉育种应对温度胁迫提供新策略。