Gene duplication at the Fascicled ear1 locus controls the fate of inflorescence meristem cells in maize.
Gene duplication at the Fascicled ear1 locus controls the fate of inflorescence meristem cells in maize.
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DOI：
10.1073/pnas.2019218118
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发表时间：
2021-02-16
影响因子：
11.1
通讯作者：
Zhang Z
中科院分区：
文献类型：
--
作者：
Du Y;Lunde C;Li Y;Jackson D;Hake S;Zhang Z
玉米穗不分枝，在单点终止。簇生穗突变体的穗和穗状花序不能作为单点生长，而是分枝。这种表型是由重复转录因子ZMM8和DRL2的错误表达引起的。我们假设这些基因重排产生了调控序列，导致早期花序分生组织的错误表达，从而激活层流程序，消融分生组织，产生分枝。这项工作表明，zmm8和drl2必须被限制在花序分生组织中以维持其末端，相反，分支可能被施加的机制。操纵这些基因可以用来改变植物的结构，潜在地改善农艺性状。植物分生组织是具有自我更新能力的多能干细胞群，以典型的模式产生侧面器官。令人感兴趣的是径向对称的分生组织是如何产生层侧器官的。显性分束穗（Fas1）突变体的雌雄花序分生组织都不能单点生长，而是呈现深分枝。两个独立的Fas1等位基因的定位克隆鉴定出一个约160 kb的区域，该区域包含两个花基因，MADS-box基因zmm8和YABBY基因下垂叶2 （drl2）。这两个基因在Fas1位点内重复，在突变的花序分生组织中时空表达错误。单独增加zmm8表达不影响花序发育；然而，zmm8、drl2及其同源物zmm14和drl1的联合错表达会扰乱分生组织的组织。我们推测，花基因在花序中的错误表达及其潜在的相互作用会导致层流程序的异位激活，从而破坏维持径向对称花序分生组织所必需的信号。与这一假设一致，RNA测序和原位分析揭示了定义分生组织和发育叶片不同区域的基因表达模式的改变。我们的研究结果强调了zmm8和drl2严格的时空表达模式的重要性，并提供了串联基因重复引起的表型的一个例子。
The maize ear is unbranched and terminates in a single point. The ear and tassel inflorescences of Fascicled ear mutants fail to grow as a single point and instead are branched. This phenotype results from the misexpression of duplicated transcription factors, ZMM8 and DRL2. We hypothesize that these gene rearrangements create regulatory sequences that cause misexpression in early inflorescence meristems, thus activating a laminar program, ablating the meristem, and producing branches. This work demonstrates that zmm8 and drl2 must be restricted from the inflorescence meristem to maintain its terminal point, and conversely, a mechanism by which branching may be imposed. Manipulation of these genes can be used to alter plant architecture, potentially to improve agronomic traits. Plant meristems are self-renewing groups of pluripotent stem cells that produce lateral organs in a stereotypical pattern. Of interest is how the radially symmetrical meristem produces laminar lateral organs. Both the male and female inflorescence meristems of the dominant Fascicled ear (Fas1) mutant fail to grow as a single point and instead show deep branching. Positional cloning of two independent Fas1 alleles identified an ∼160 kb region containing two floral genes, the MADS-box gene, zmm8, and the YABBY gene, drooping leaf2 (drl2). Both genes are duplicated within the Fas1 locus and spatiotemporally misexpressed in the mutant inflorescence meristems. Increased zmm8 expression alone does not affect inflorescence development; however, combined misexpression of zmm8, drl2, and their syntenic paralogs zmm14 and drl1, perturbs meristem organization. We hypothesize that misexpression of the floral genes in the inflorescence and their potential interaction cause ectopic activation of a laminar program, thereby disrupting signaling necessary for maintenance of radially symmetrical inflorescence meristems. Consistent with this hypothesis, RNA sequencing and in situ analysis reveal altered expression patterns of genes that define distinct zones of the meristem and developing leaf. Our findings highlight the importance of strict spatiotemporal patterns of expression for both zmm8 and drl2 and provide an example of phenotypes arising from tandem gene duplications.
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影响因子：
7.7
作者：
Caggiano MP;Yu X;Bhatia N;Larsson A;Ram H;Ohno CK;Sappl P;Meyerowitz EM;Jönsson H;Heisler MG
通讯作者：
Heisler MG
影响因子：
11.6
作者：
Han, Jong-Jin;Jackson, David;Martienssen, Robert
通讯作者：
Martienssen, Robert
影响因子：
11.6
作者：
Jeon, JS;Jang, S;An, G
通讯作者：
An, G
影响因子：
30.8
作者：
Il Je, Byoung;Gruel, Jeremy;Jackson, David
通讯作者：
Jackson, David
DOI：
10.1073/pnas.1406446111
发表时间：
2014-10-07
影响因子：
11.1
作者：
Daum, Gabor;Medzihradszky, Anna;Lohmann, Jan U.
通讯作者：
Lohmann, Jan U.