TWIN SISTER OF FT (TSF) acts as a floral pathway integrator redundantly with FT
TWIN SISTER OF FT (TSF) acts as a floral pathway integrator redundantly with FT
复制标题
DOI：
10.1093/pcp/pci151
复制
发表时间：
2005-08-01
影响因子：
4.9
通讯作者：
Araki, T
中科院分区：
文献类型：
--
作者：
Yamaguchi, A;Kobayashi, Y;Araki, T
在拟南芥中，控制花转变（开花）的几个遗传途径被整合到 FT、LFY 和 SOC1 的转录调控中。 TSF 是拟南芥中 FT 最接近的同源物。 CONSTANS (CO) 激活后，TSF 表达迅速诱导。 TSF 和 FT 的 mRNA 水平显示出相似的昼夜振荡模式和对光周期的响应：晚间峰值，长日照 (LD) 条件下的水平高于短日照 (SD) 条件，并且在日长延长时立即上调。这些观察结果表明，TSF 是 CO 的直接调控目标。tsf 突变在 SD 条件下延迟开花，并在 LD 和 SD 条件下增强 ft 表型。 TSF 和 FT 也具有相似的 FLC 调节模式，FLC 是自主和春化途径的整合者，以及 EBS 和 PHYB 等其他因素。一致地，TSF 过度表达导致早熟开花表型，与光周期、CO 或 FLC 无关。这些观察结果表明，TSF 是花途径整合子的新成员，促进开花很大程度上与 FT 多余，但在 SD 条件下做出了明显的贡献。 TSF 和 FT 似乎彼此独立且独立于 LFY，并且部分位于 SOC1 上游。有趣的是，尽管 TSF 和 FT 在韧皮部组织中表达，但幼苗中 TSF 和 FT 的表达模式并不重叠。我们的工作揭示了通路整合水平上监管网络的额外复杂性和空间方面。我们认为韧皮部是 FT 和 TSF 转录调控中多种调控途径整合的部位。
In Arabidopsis, several genetic pathways controlling the floral transition (flowering) are integrated at the transcriptional regulation of FT, LFY and SOC1. TSF is the closest homolog of FT in Arabidopsis. TSF expression was induced rapidly upon activation of CONSTANS (CO). The mRNA levels of TSF and FT showed similar patterns of diurnal oscillation and response to photoperiods: an evening peak, higher levels in long day (LD) than in short day (SD) conditions, and immediate up-regulation upon day-length extension. These observations suggest that TSF is a direct regulatory target of CO. tsf mutation delayed flowering in SD conditions and enhanced the phenotype of ft in both LD and SD conditions. TSF and FT also shared similar modes of regulation by FLC, an integrator of autonomous and vernalization pathways, and other factors such as EBS and PHYB. Consistently, TSF overexpression caused a precocious flowering phenotype independent of photoperiods or CO, or FLC. These observations suggest that TSF is a new member of the floral pathway integrators and promotes flowering largely redundantly with FT but makes a distinct contribution in SD conditions. TSF and FT seem to act independently of each other and of LFY, and partially upstream of SOC1. Interestingly, the expression patterns of TSF and FT in seedlings did not overlap, although both were expressed in the phloem tissues. Our work revealed additional complexity and spatial aspects of the regulatory network at the pathway integration level. We propose that the phloem is the site where multiple regulatory pathways are integrated at the transcriptional regulation of FT and TSF.