Hoopes Genevieve M, Zarka Daniel, Feke Ann, Acheson Kaitlyn, Hamilton John P, Douches David, Buell C Robin, Farré Eva M
Department of Plant Biology Michigan State University East Lansing Michigan USA.
Department of Plant, Soil, and Microbial Sciences Michigan State University East Lansing Michigan USA.
Plant Direct. 2022 Jul 12;6(7):e425. doi: 10.1002/pld3.425. eCollection 2022 Jul.
The circadian clock is an internal molecular oscillator and coordinates numerous physiological processes through regulation of molecular pathways. Tissue-specific clocks connected by mobile signals have previously been found to run at different speeds in tissues. However, tissue variation in circadian clocks in crop species is unknown. In this study, leaf and tuber global gene expression in cultivated potato under cycling and constant environmental conditions was profiled. In addition, we used a circadian-regulated luciferase reporter construct to study tuber gene expression rhythms. Diel and circadian expression patterns were present among 17.9% and 5.6% of the expressed genes in the tuber. Over 500 genes displayed differential tissue specific diel phases. Intriguingly, few core circadian clock genes had circadian expression patterns, while all such genes were circadian rhythmic in cultivated tomato leaves. Furthermore, robust diel and circadian transcriptional rhythms were observed among detached tubers. Our results suggest alternative regulatory mechanisms and/or clock composition is present in potato, as well as the presence of tissue-specific independent circadian clocks. We have provided the first evidence of a functional circadian clock in below-ground storage organs, holding important implications for other storage root and tuberous crops.
生物钟是一种内部分子振荡器，通过调节分子途径来协调众多生理过程。此前发现，由移动信号连接的组织特异性生物钟在不同组织中运行速度不同。然而，作物物种生物钟的组织差异尚不清楚。在本研究中，对栽培马铃薯在循环和恒定环境条件下的叶片和块茎进行了全基因组表达分析。此外，我们使用了一个受生物钟调节的荧光素酶报告构建体来研究块茎基因表达节律。在块茎中，17.9%和5.6%的表达基因呈现昼夜和生物钟表达模式。超过500个基因表现出不同的组织特异性昼夜阶段。有趣的是，几乎没有核心生物钟基因具有生物钟表达模式，而所有这些基因在栽培番茄叶片中都有生物钟节律。此外，在离体块茎中观察到了强烈的昼夜和生物钟转录节律。我们的结果表明，马铃薯中存在替代调节机制和/或生物钟组成，以及组织特异性独立生物钟的存在。我们首次提供了地下贮藏器官中功能性生物钟的证据，这对其他贮藏根和块茎作物具有重要意义。
