花器官发育需要经过三个连续步骤：花分生组织的诱导、花器官轮生模式的形成以及各轮花器官组织细胞的分化和生长。目前关于花器官发育第三阶段功能基因的报道还很少。我们利用图位克隆法分离了一个在水稻花器官发育第三阶段发挥作用的基因BLS1，该基因功能缺失将影响内外稃细胞大小，导致内外稃表型异常。关于BLS1基因如何控制内外稃细胞的发育和生长，影响花器官形态建成的分子机制现在还并不了解。本项目拟在现有基础上，通过酵母双杂交、BiFC等技术鉴定与BLS1互作的BIP蛋白（BLS1-Interacting Protein），过表达和干扰BIP基因分析其对花器官发育的影响，RNA-seq分析BLS1可能作用的下游基因。这些研究旨在解析BLS1信号转导途径及其调控网络，阐明BLS1调控花器官发育的分子机制。研究结果对于理解花器官发育第三阶段基因在花器官形态建成中的作用具有重要意义。

Flower development includes three sequential steps, floral-meristem induction, floral-organ pattering and floral tissue and cell differentiation. However, it is rarely reported about the genes served in the third stage of flower formation. By map-based cloning, we isolated BLS1 (BEAK LIKE SPIKELET1) gene, which belongs to the type of the gene in the third stage development. When BLS1 function defects, cell size decreased and generated altered shapes of lemma and palea. However, the molecular mechanism of BLS1 controlling lemma and palea cells development and specification of floral morphology remains unclear. On basis of present studies, we intend to identify BLS1 interacting proteins (BIP) through yeast two-hybrid assays and bimolecular fluorescence complementation technique, analyze the function of BIP by over-expressing and RNA interference, and explore the downstream genes of BLS1 by RNA-seq approach. These studies may help us to uncover the signal transduction pathway and regulatory network of BLS1 gene, and then reveal the molecular mechanism of floral development controlling by BLS1. It is also of great importance for us to understand the role and function of the genes served in the third stage of the floral organ morphogenesis.