Systemin, a peptide plant hormone of 18 amino acids, coordinates local and systemic immune responses. The activation of the canonical systemin-mediated systemic signaling pathway involves systemin release from its precursor prosystemin, systemin binding to its membrane receptor SYSTEMIN RECEPTOR1 (SYR1), and the transport of long-distance signaling molecules, including jasmonic acid, the prosystemin mRNA, volatile organic compounds and possibly systemin itself. Here, we review emerging evidence that the disordered structure and unconventional processing and secretion of systemin contribute to the regulation of systemin-mediated signaling during plant defense. We highlight recent advances in systemin research, which elucidated how cells integrate multiple long-distance signals into the systemic defense response. In addition, we discuss the perception of systemin by SYR1 and its mediation of downstream defense responses.

中文翻译：

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Systemin介导的远程系统防御反应。

Systemin是一种由18个氨基酸组成的肽类植物激素，可协调局部和全身免疫反应。规范性systemin介导的系统信号通路的激活涉及systemin从其前体prosystemin释放，systemin与其膜受体SYSTEMIN RECEPTOR1（SYR1）结合以及长途信号分子（包括茉莉酸，prosystemin mRNA，挥发性）的运输有机化合物，也可能是系统本身。在这里，我们审查了新兴的证据表明，systemin的无序结构和非常规加工与分泌有助于植物防御过程中systemin介导的信号的调节。我们重点介绍了系统研究的最新进展，阐明了细胞如何将多个长途信号整合到系统防御反应中。此外，