Defying Gravity: WEEP promotes negative gravitropism in Prunus persica (peach) shoots and roots by establishing asymmetric auxin gradients.
Defying Gravity: WEEP promotes negative gravitropism in Prunus persica (peach) shoots and roots by establishing asymmetric auxin gradients.
复制标题
对抗重力：WEEP 通过建立不对称的生长素梯度来促进桃（桃）芽和根的负向地性。
DOI：
10.1101/2023.05.26.542472
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Hollender,CourtneyA
中科院分区：
文献类型：
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作者：
Kohler,AndreaR;Scheil,Andrew;HillJr,JosephL;Allen,JeffreyR;Al-Haddad,JameelM;Goeckeritz,CharityZ;Strader,LuciaC;Telewski,FrankW;Hollender,CourtneyA
带有垂枝结构的树木因其美丽而受到重视，是了解植物如何调节姿势控制的巨大资源。桃的哭泣表型具有向下的椭圆形拱形分支，是由weep基因的纯合子突变引起的。到目前为止，人们对WEEP蛋白的功能知之甚少，尽管它在整个植物中高度保守。在这里，我们介绍了解剖学、生化、生物力学、生理学和分子实验的结果，这些实验为我们提供了对泪水功能的洞察。我们的数据表明，垂桃在枝条结构上没有缺陷。相反，标准枝和垂枝顶端近轴(上部)和背面(下部)的转录本揭示了与早期生长素反应、组织图案化、细胞伸长和张力木发育相关的基因的翻转表达模式。这表明，在新梢向重力反应过程中，WEEP促进了生长素向下侧的极性运输，导致细胞伸长和木材拉伸发育。此外，落叶桃树表现出更陡峭的根系和更快的向根重力反应，就像大麦和小麦的落叶同源基因EGT2发生突变一样。这表明，在向重力性作用过程中，WEEP在调节外侧器官角度和取向方面的作用可能是保守的。此外，尺寸排除层析表明，WEEP蛋白像其他SAM结构域蛋白一样可以自我寡聚。这种寡聚作用可能是WEEP在生长素运输过程中形成蛋白质复合体所必需的。总而言之，我们对垂桃的研究结果为我们提供了与向重力性以及侧枝和根方向相关的生长素极地运输机制的新见解。
Trees with weeping shoot architectures are valued for their beauty and serve as tremendous resources for understanding how plants regulate posture control. The Prunus persica (peach) weeping phenotype, which has elliptical downward arching branches, is caused by a homozygous mutation in the WEEP gene. Until now, little was known about the function of WEEP protein despite its high conservation throughout Plantae. Here, we present the results of anatomical, biochemical, biomechanical, physiological, and molecular experiments that provide insight into WEEP function. Our data suggest that weeping peach does not have defects in branch structure. Rather, transcriptomes from the adaxial (upper) and abaxial (lower) sides of standard and weeping branch shoot tips revealed flipped expression patterns for genes associated with early auxin response, tissue patterning, cell elongation, and tension wood development. This suggests that WEEP promotes polar auxin transport toward the lower side during shoot gravitropic response, leading to cell elongation and tension wood development. In addition, weeping peach trees exhibited steeper root systems and faster root gravitropic response, just as barley and wheat with mutations in their WEEP homolog EGT2. This suggests that the role of WEEP in regulating lateral organ angles and orientations during gravitropism may be conserved. Additionally, size-exclusion chromatography indicated that WEEP proteins self-oligomerize, like other SAM-domain proteins. This oligomerization may be required for WEEP to function in formation of protein complexes during auxin transport. Collectively, our results from weeping peach provide new insight into polar auxin transport mechanisms associated with gravitropism and lateral shoot and root orientation.