School of Pharmacy, Kitasato University, Tokyo, Japan.
Life Sciences and Biotechnology Department, Tokyo Institute of Technology, Tokyo, Japan.
BMC Genomics. 2022 May 30;22(Suppl 5):920. doi: 10.1186/s12864-022-08609-2.
Aggression is an evolutionarily conserved behavior critical for animal survival. In the fish Betta splendens, across different stages of fighting interactions, fighting opponents suffer from various stressors, especially from the great demand for oxygen. Using RNA sequencing, we profiled differential alternative splicing (DAS) events in the brains of fish collected before fighting, during fighting, and after fighting to study the involvement of alternative splicing (AS) in the response to stress during the fight.
We found that fighting interactions induced the greatest increase in AS in the 'during-fighting' fish, followed by that of the 'after-fighting' fish. Intron retention (IR) was the most enriched type among all the basic AS events. DAS genes were mainly associated with synapse assembly, ion transport, and regulation of protein secretion. We further observed that IR events significantly differentiated between winners and losers for 19 genes, which were associated with messenger RNA biogenesis, DNA repair, and transcription machinery. These genes share many common features, including shorter intron length and higher GC content.
This study is the first comprehensive view of AS induced by fighting interactions in a fish species across different stages of those interactions, especially with respect to IR events in winners and losers. Together, these findings facilitate future investigations into transcriptome complexity and AS regulation in response to stress under the context of aggression in vertebrates.
攻击行为是一种进化上保守的行为，对动物的生存至关重要。在鱼类斗鱼中，在不同的战斗互动阶段，战斗对手会遭受各种应激源的影响，尤其是对氧气的巨大需求。通过 RNA 测序，我们对战斗前、战斗中和战斗后采集的鱼类大脑中的差异剪接（DAS）事件进行了分析，以研究剪接（AS）在战斗过程中应对应激反应中的作用。
我们发现，战斗互动在“战斗中”的鱼类中诱导的 AS 增加最大，其次是“战斗后”的鱼类。内含子保留（IR）是所有基本 AS 事件中最丰富的类型。DAS 基因主要与突触组装、离子转运和蛋白质分泌调节有关。我们进一步观察到，IR 事件在 19 个基因的赢家和输家中显著区分，这些基因与信使 RNA 生物发生、DNA 修复和转录机制有关。这些基因有许多共同的特征，包括较短的内含子长度和较高的 GC 含量。
本研究首次全面观察了鱼类在不同战斗互动阶段的战斗互动诱导的 AS，特别是胜利者和失败者的 IR 事件。这些发现为未来在脊椎动物攻击背景下研究应激反应中转录组复杂性和 AS 调节提供了便利。
