纽约大学Claude Desplan团队取得一项新突破。他们研制了转录干扰确保每个蚂蚁神经元有一个嗅觉受体。相关论文发表在2025年10月22日出版的《自然》杂志上。

在这里，课题组人员发现，在蚂蚁Harpegnathos saltator中，每个嗅觉感觉神经元激活Or基因阵列中的单个启动子，产生成熟的帽状和多腺苷化mRNA。虽然阵列中下游基因的启动子是无活性的，但由于活性启动子的转录读通，所有下游基因仍然被转录，可能是由低效的RNA聚合酶II终止。这种解读似乎通过转录干扰抑制下游启动子，导致不翻译的异常非封顶转录物，确保只有活性基因被表达。同时，来自所选的Or启动子的长反义转录覆盖上游基因，可能使它们沉默。因此，蚂蚁似乎进化出了一种独特的基于转录干扰的机制，可以从一系列具有功能相似启动子的OR基因中表达单个OR蛋白。

据了解，为了确保特异性，感觉神经元通常从庞大的基因家族中选择并表达单一受体，遵循“每个神经元一个受体”的规则。例如，哺乳动物的每个嗅觉感觉神经元只表达一个气味受体（Or）基因。果蝇大约有60个基因，这种选择是决定性的。相比之下，老鼠面临着从1000多个选项中选择一个或基因的挑战。他们通过随机选择的复杂系统来解决这个问题。蚂蚁也拥有许多Or基因，其中大多数与哺乳动物相似，被组织成串联阵列，但它们的调节机制是独立进化的。

附：英文原文

Title: Transcriptional interferences ensure one olfactory receptor per ant neuron

Author: Sieriebriennikov, Bogdan, Kolumba, Olena, de Beaurepaire, Aurore, Wu, Jennifer, Fambri, Valentina, Bardol, Eva, Zhong, Yuwei, Gainetdinov, Ildar, Reinberg, Danny, Yan, Hua, Desplan, Claude

Issue&Volume: 2025-10-22

Abstract: To ensure specificity, sensory neurons must select and express a single receptor from often vast gene families, adhering to the rule of ‘one receptor per neuron’. For example, each olfactory sensory neuron in mammals expresses only one odorant receptor (Or) gene1,2. In Drosophila, which has about 60 Or genes, this selection is deterministic3. By contrast, mice face the challenge of choosing one Or gene from over 1,000 options4. They solve this through a complex system of stochastic choices5,6,7,8,9. Ants also possess many Or genes, most of which are organized into tandem arrays similar to those in mammals, but their regulatory mechanisms have evolved independently. Here we show that, in the ant Harpegnathos saltator, each olfactory sensory neuron activates a single promoter within an Or gene array, producing a mature capped and polyadenylated mRNA. While the promoters of downstream genes in the array are inactive, all downstream genes are nonetheless transcribed due to transcriptional readthrough from the active promoter, probably caused by inefficient RNA polymerase II termination. This readthrough appears to suppress downstream promoters through transcriptional interference, resulting in aberrant non-capped transcripts that are not translated, ensuring that only the active gene is expressed. Simultaneously, long antisense transcription originating from the chosen Or promoter covers upstream genes, presumably silencing them. Ants therefore appear to have evolved a unique transcriptional-interference-based mechanism to express a single OR protein from an array of Or genes with functionally similar promoters.

DOI: 10.1038/s41586-025-09664-x

Source: https://www.nature.com/articles/s41586-025-09664-x