Sengupta Aniket, Hileman Lena C
The Hileman Lab, Department of Ecology and Evolutionary Biology, The University of Kansas, Lawrence, KS, United States.
Front Plant Sci. 2018 Oct 26;9:1561. doi: 10.3389/fpls.2018.01561. eCollection 2018.
A common feature in developmental networks is the autoregulation of transcription factors which, in turn, positively or negatively regulate additional genes critical for developmental patterning. When a transcription factor regulates its own expression by binding to -regulatory sites in its gene, the regulation is direct transcriptional autoregulation (DTA). Indirect transcriptional autoregulation (ITA) involves regulation by proteins expressed downstream of the target transcription factor. We review evidence for a hypothesized role of DTA in the evolution and development of novel flowering plant phenotypes. We additionally provide new bioinformatic and experimental analyses that support a role for transcriptional autoregulation in the evolution of flower symmetry. We find that 5' upstream non-coding regions are significantly enriched for predicted autoregulatory sites in Lamiales genes-an upstream regulator of flower monosymmetry. This suggests a possible correlation between autoregulation of and the origin of monosymmetric flowers near the base of Lamiales, a pattern that may be correlated with independently derived monosymmetry across eudicot lineages. We find additional evidence for transcriptional autoregulation in the flower symmetry program, and report that may undergo ITA. In light of existing data and new data presented here, we hypothesize how -acting autoregulatory sites originate, and find evidence that such sites (and DTA) can arise subsequent to the evolution of a novel phenotype.
发育网络中的一个共同特征是转录因子的自我调节，而转录因子又会对发育模式至关重要的其他基因进行正向或负向调节。当转录因子通过与其基因中的调控位点结合来调节自身表达时，这种调节就是直接转录自我调节（DTA）。间接转录自我调节（ITA）涉及由目标转录因子下游表达的蛋白质进行的调节。我们综述了关于DTA在新型开花植物表型的进化和发育中所起假设作用的证据。我们还提供了新的生物信息学和实验分析，支持转录自我调节在花对称性进化中的作用。我们发现唇形目基因（花单对称性的上游调节因子）的5'上游非编码区在预测的自我调节位点上显著富集。这表明 的自我调节与唇形目基部附近单对称花的起源之间可能存在关联，这种模式可能与真双子叶植物谱系中独立衍生的单对称性相关。我们在花对称性程序中发现了转录自我调节的更多证据，并报告 可能经历ITA。鉴于现有数据和本文提出的新数据，我们推测顺式作用自我调节位点是如何起源的，并发现证据表明这些位点（和DTA）可能在新表型进化之后出现。
