HOMEODOMAIN PROTEIN8 mediates jasmonate-triggered trichome elongation in tomato
HOMEODOMAIN PROTEIN8 mediates jasmonate-triggered trichome elongation in tomato
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DOI：
10.1111/nph.17216
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发表时间：
2021-02-26
期刊：
影响因子：
9.4
通讯作者：
Wu, Shuang
中科院分区：
文献类型：
--
作者：
Hua, Bing;Chang, Jiang;Wu, Shuang
植物激素可以调节植物的生理和发育，以增强其对生物和非生物挑战的适应能力。茉莉酸 (JA) 是植物中的免疫激素之一，可引发全基因组转录变化以应对昆虫攻击和伤害。尽管已知 JA 会影响毛状体的发育，表皮附属物形成针对各种应激的保护性屏障，但目前尚不清楚 JA 如何与调节毛状体发育的发育程序相互作用。在这项研究中，我们表明 JA 通过释放 Jasmonate ZIM (JAZ) 蛋白介导的转录抑制来影响番茄毛状体的长度。我们确定了 SlJAZ4（一种优先在毛状体中表达的负调节因子）作为番茄毛状体中 JA 信号传导的关键成分。我们还确定了同源域亮氨酸拉链基因 SlHD8，作为 JA 信号传导的下游调节因子，促进毛状体伸长。 SlHD8 在毛状体中也高度表达，并与 SlJAZ4 发生物理相互作用。 SlHD8 的功能缺失突变导致毛状体变短，这种表型只能通过茉莉酸甲酯处理得到部分挽救。我们的双荧光素酶和染色质免疫沉淀定量 PCR 检测显示，SlHD8 通过直接与一组细胞壁松弛蛋白基因的启动子结合并激活其转录来调节毛状体伸长。总之，我们的研究结果将 SlHD8-SlJAZ4 定义为介导 JA 诱导的番茄毛状体伸长的关键模块。
Plant hormones can adjust the physiology and development of plants to enhance their adaptation to biotic and abiotic challenges. Jasmonic acid (JA), one of the immunity hormones in plants, triggers genome-wide transcriptional changes in response to insect attack and wounding. Although JA is known to affect the development of trichomes, epidermal appendages that form a protective barrier against various stresses, it remains unclear how JA interacts with developmental programs that regulate trichome development.In this study, we show that JA affects trichome length in tomato by releasing the transcriptional repression mediated by Jasmonate ZIM (JAZ) proteins. We identified SlJAZ4, a negative regulator preferentially expressed in trichomes, as the critical component in JA signaling in tomato trichomes.We also identified a homeodomain-leucine zipper gene, SlHD8, as the downstream regulator of JA signaling that promotes trichome elongation. SlHD8 is also highly expressed in trichomes and physically interacts with SlJAZ4. Loss-of-function mutations in SlHD8 caused shorter trichomes, a phenotype that was only partially rescued by methyl jasmonate treatment.Our dual-luciferase and chromatin immunoprecipitation-quantitative PCR assays revealed that SlHD8 regulates trichome elongation by directly binding to the promoters of a set of cell-wall-loosening protein genes and activating their transcription. Together, our findings define SlHD8-SlJAZ4 as a key module mediating JA-induced trichome elongation in tomato.