PRX9 and PRX40 Are Extensin Peroxidases Essential for Maintaining Tapetum and Microspore Cell Wall Integrity during Arabidopsis Anther Development
PRX9 and PRX40 Are Extensin Peroxidases Essential for Maintaining Tapetum and Microspore Cell Wall Integrity during Arabidopsis Anther Development
复制标题
DOI：
10.1105/tpc.18.00907
复制
发表时间：
2019-04-01
期刊：
影响因子：
11.6
通讯作者：
Weng, Jing-Ke
中科院分区：
文献类型：
--
作者：
Jacobowitz, Joseph R.;Doyle, William C.;Weng, Jing-Ke
花粉和小孢子发育是产生雄性配子的所有陆地植物生命周期中的重要步骤。在开花植物中，花粉发育发生在花药内部。在这里，我们报告了两个 III 类过氧化物酶编码基因 PEROXIDASE9 (PRX9) 和 PRX40 的鉴定，它们在遗传上是冗余的，对于拟南芥 (Arabidopsis thaliana) 的花药和花粉正常发育至关重要。缺乏功能性PRX9和PRX40的拟南芥双突变体是雄性不育的。突变的花药表现出肿胀、肥大的绒毡层细胞和花粉粒，表明细胞壁完整性被破坏。这些表型导致花药成熟时几乎 100% 的渗透性花粉变性。使用免疫化学和生化方法，我们表明 PRX9 和 PRX40 可能会交联延伸蛋白，从而有助于花药发育过程中绒毡层细胞壁的完整性。这项工作表明 PRX9 和 PRX40 编码拟南芥延伸蛋白过氧化物酶，并强调了延伸蛋白交联在花粉发育过程中的重要性。
Pollen and microspore development are essential steps in the life cycle of all land plants that generate male gametes. Within flowering plants, pollen development occurs inside of the anther. Here, we report the identification of two class III peroxidase-encoding genes, PEROXIDASE9 (PRX9) and PRX40, that are genetically redundant and essential for proper anther and pollen development in Arabidopsis (Arabidopsis thaliana). Arabidopsis double mutants devoid of functional PRX9 and PRX40 are male sterile. The mutant anthers display swollen, hypertrophic tapetal cells and pollen grains, suggesting disrupted cell wall integrity. These phenotypes lead to nearly 100%-penetrant pollen degeneration upon anther maturation. Using immunochemical and biochemical approaches, we show that PRX9 and PRX40 likely cross-link extensins to contribute to tapetal cell wall integrity during anther development. This work suggests that PRX9 and PRX40 encode Arabidopsis extensin peroxidases and highlights the importance of extensin cross-linking during pollen development.