The Eugene Bell Center, The Marine Biological Laboratory, Woods Hole, Massachusetts, USA; email:
Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel.
Annu Rev Anim Biosci. 2023 Feb 15;11:57-75. doi: 10.1146/annurev-animal-060322-114534.
The coleoid cephalopods have the largest brains, and display the most complex behaviors, of all invertebrates. The molecular and cellular mechanisms that underlie these remarkable advancements remain largely unexplored. Early molecular cloning studies of squid ion channel transcripts uncovered an unusually large number of A→I RNA editing sites that recoded codons. Further cloning of other neural transcripts showed a similar pattern. The advent of deep-sequencing technologies and the associated bioinformatics allowed the mapping of RNA editing events across the entire neural transcriptomes of various cephalopods. The results were remarkable: They contained orders of magnitude more recoding editing sites than any other taxon. Although RNA editing sites are abundant in most multicellular metazoans, they rarely recode. In cephalopods, the majority of neural transcripts are recoded. Recent studies have focused on whether these events are adaptive, as well as other noncanonical aspects of cephalopod RNA editing.
头足类软体动物拥有所有无脊椎动物中最大的大脑，并表现出最复杂的行为。这些显著进步背后的分子和细胞机制在很大程度上仍未被探索。早期对鱿鱼离子通道转录本的分子克隆研究发现了大量非同寻常的 A→I RNA 编辑位点，这些编辑位点重新编码密码子。对其他神经转录本的进一步克隆显示出类似的模式。高通量测序技术的出现和相关的生物信息学方法允许在各种头足类动物的整个神经转录组中绘制 RNA 编辑事件图谱。结果令人瞩目：它们包含的重新编码编辑位点数量远远超过任何其他分类群。尽管 RNA 编辑位点在大多数多细胞后生动物中很丰富，但它们很少重新编码。在头足类动物中，大多数神经转录本都被重新编码。最近的研究集中在这些事件是否具有适应性，以及头足类动物 RNA 编辑的其他非典型方面。
