Data from: Transcriptome dynamics over a lunar month in a broadcast spawning Acroporid coral

On one night per year, at a specific point in the lunar cycle, one of the most extraordinary reproductive events on the planet unfolds as hundreds of millions of broadcast spawning corals release their trillions of gametes into the waters of the tropical seas. Each species spawns on a specific night within the lunar cycle, typically from full moon to third quarter moon, and in a specific time window after sunset. This accuracy is essential to achieve efficient fertilization in the vastness of the oceans. In this report we use transcriptome sequencing at noon and midnight across an entire lunar cycle to explore how Acroporid corals interpret lunar signals. The data were interrogated by both time of day dependent and independent methods to identify different types of lunar cycles. Time of day methods found that genes associated with biological clocks and circadian processes change their diurnal cycles over the course of a synodic lunar cycle. Some genes have large differences between day and night at some lunar phases, but little or no diurnal differences at other phases. Many clock genes display an oscillation pattern indicative of phase shifts linked to the lunar cycle. Time independent methods found that signal transduction, protein secretion and modification, cell cycle and ion transport change over the lunar time scale, and peak at various phases of the moon. Together these data provide unique insights into how the moon impinges on coral transcription cycles how lunar light may regulate circalunar timing systems and coral biology.

每年在月球周期的特定时刻，地球上最非凡的繁殖事件之一便会上演：数亿株散播产卵型珊瑚将万亿计的配子释放至热带海域水体中。每个珊瑚物种都会在月球周期内的特定夜晚产卵，通常处于满月至下弦月时段，且在日落之后的特定时间窗口内进行。这种精准性对于在广袤海洋中实现高效受精至关重要。
本研究中，我们通过在完整月球周期内的正午与午夜开展转录组测序，探究轴孔珊瑚（Acroporid）如何解读月球信号。我们采用依赖昼夜时段与不依赖昼夜时段的两类分析方法对数据进行解析，以甄别不同类型的月球周期。依赖昼夜时段的分析方法发现，与生物钟及昼夜节律过程相关的基因，其昼夜周期会在朔望月（synodic lunar cycle）的进程中发生改变：部分基因在部分月相时段的昼夜表达差异显著，但在其他月相时段几乎无昼夜差异。众多时钟基因呈现出与月球周期相关的相位偏移特征的振荡模式。不依赖昼夜时段的分析方法则发现，信号转导、蛋白质分泌与修饰、细胞周期以及离子转运相关的基因表达会随月球时间尺度发生变化，并在不同月相时段达到峰值。
综上，本研究数据为月球如何影响珊瑚的转录周期，以及月球光照如何调控近月节律（circalunar）计时系统与珊瑚生物学特性提供了独特的研究视角。