Glotzer Giacomo L, Pastor P Daniel H, Kronauer Daniel J C
Laboratory of Social Evolution and Behavior, The Rockefeller University, New York, NY 10065, USA.
Howard Hughes Medical Institute, New York, NY 10065, USA.
bioRxiv. 2025 Aug 21:2025.08.21.671318. doi: 10.1101/2025.08.21.671318.
Communication is crucial to social life, and in ants, it is mediated primarily through olfaction. Ants have more odorant receptor (OR) genes than any other group of insects, generated through tandem duplications that produce large genomic arrays of related genes. However, how olfactory sensory neurons produce a single functional OR from these arrays remains unclear. In ants, only mRNA from one OR in an array is exported into the cytoplasm, while upstream genes are silent and transcripts from downstream genes remain nuclear. Here, we show that non-canonical readthrough transcription in the downstream direction generates non-translated transcripts. We also find that OR promoters are bidirectional, producing antisense long non-coding RNAs that appear to suppress the expression of upstream genes. Finally, we present evidence that this regulatory architecture is conserved across ants and bees, suggesting that this mechanism for functionally monogenic OR expression is widespread in insects with expanded OR repertoires.
交流对社会生活至关重要，在蚂蚁中，交流主要通过嗅觉介导。蚂蚁拥有比其他任何昆虫群体都更多的气味受体（OR）基因，这些基因通过串联重复产生大量相关基因的基因组阵列。然而，嗅觉感觉神经元如何从这些阵列中产生单个功能性OR仍不清楚。在蚂蚁中，阵列中只有一个OR的mRNA被输出到细胞质中，而上游基因保持沉默，下游基因的转录本则保留在细胞核中。在这里，我们表明下游方向的非经典通读转录产生非翻译转录本。我们还发现OR启动子是双向的，产生反义长链非编码RNA，似乎抑制上游基因的表达。最后，我们提供证据表明这种调控结构在蚂蚁和蜜蜂中是保守的，这表明这种功能性单基因OR表达的机制在具有扩展OR库的昆虫中广泛存在。
