Role of the bZIP transcription factor PERIANTHIA in the regulatory network underlying meristem function and floral patterning

该建议旨在阐明PERIANTHIA（PAN），bZIP转录因子，在调控网络中的作用，分生组织功能和花图案的机制水平。PAN在茎顶端分生组织和幼花原基中都有活性，在那里它是正确确定花被器官数目所必需的。我们发现，除了这一作用，PAN通过激活AGAMOUS（AG）在花发育中具有重要功能，AGAMOUS是图案形成以及干细胞控制所必需的核心调节因子。此外，泛突变影响茎尖分生组织中干细胞系统的中心参与者的表达。我们现在建议研究PAN是如何能够控制这两个非常不同的功能，即细胞增殖在芽分生组织和细胞分化在新兴的花朵。具体目标是：（1）通过表达谱分析和全基因组结合研究鉴定PAN靶点。(2)PAN辅因子的鉴定和分析。(3)在PAN网络中发现新基因。(4)PAN整合到已知的分生组织控制和花模式的调控网络中。(5)对PAN规则的机械理解。该项目将大大推进我们对分生组织功能和花图案的调控网络的理解，并阐明PAN如何作为分生组织细胞增殖和分化之间的分子开关。在基础设施层面，社区不仅将受益于产生的大规模数据集，更重要的是我们将在项目期间实现的染色质免疫沉淀与微阵列检测技术的进步。这些技术将立即提供给其他AFGN/NSF 2010团体，甚至在出版之前。

This proposal is aimed at elucidating the role of PERIANTHIA (PAN), a bZIP transcription factor, in the regulatory network that underlies meristem function and floral patterning on a mechanistic level. PAN is active both in the shoot apical meristem as well as in young floral primordia, where it is necessary for the correct specification of perianth organ number. We have found that in addition to this role, PAN has important functions in floral development by activating AGAMOUS (AG), a core regulator necessary for patterning as well as stem cell control. Furthermore, pan mutations affect the expression of central players of the stem cell system in the shoot apical meristem. We are now proposing to study how PAN is able to control these two very diverse functions, namely cell proliferation in the shoot meristem and cell differentiation in emerging flowers. The specific aims are: (1) Identification of PAN targets by expression profiling and genome-wide binding studies. (2) Identification and analysis of PAN co-factors. (3) Discovery of novel genes in the PAN network. (4) Integration of PAN into known regulatory networks of meristem control and floral patterning. (5) Mechanistic understanding of PAN regulation. The proposed project will substantially advance our understanding of the regulatory network underlying meristem function and floral patterning and elucidate how can PAN act as a molecular switch between proliferation and differentiation of meristematic cells. On the infrastructure level, the community will not only benefit from the large-scale datasets produced, but more importantly from the advancements in chromatin-immunoprecipitation with microarray detection technologies we will achieve during the project. These technologies will be made available to other AFGN/NSF2010 groups immediately, even prior to publication.