Greiffer Luise, Ressmann Luka, Kaiser Charlotte Sophia, Liebau Eva, Spiegler Verena
Institute for Pharmaceutical Biology and Phytochemistry, University of Münster, Münster, Germany.
Institute of Integrative Cell Biology and Physiology, University of Münster, Münster, Germany.
Sci Rep. 2025 Aug 11;15(1):29399. doi: 10.1038/s41598-025-11651-1.
Salivary proline-rich proteins (PRPs) represent a common mechanism of defense against tannins in mammals. Few reports exist regarding the occurrence or PRPs with similar function in nematodes and none of these proteins or their coding genes have been functionally characterized so far. In Caenorhabditis elegans, two genes (clx-1 and T22D1.2) were strongly induced upon tannin treatment of the nematodes, both of them potentially encoding proline-rich proteins. Therefore, translation of these genes into proteins was confirmed and the expression pattern was investigated in more detail. Particularly T22D1.2 was found to be exclusively up-regulated in worms treated with test substances possessing astringent properties, especially tannins, whereas no expression was observed for any other stressor or in the untreated control group. Similar to mammalian PRPs, repetitive proline-rich sequences were identified in both of the corresponding proteins. A potential role in tannin defense was supported by an increased survival of tannin-treated worms when T22D1.2 was constitutively expressed under the vit-5 promoter. However, no differences were observed in the clx-1 and T22D1.2 knockout mutants in comparison to the wild type, respectively. Within the current study, evidence was provided for the existence of repetitive proline-rich proteins in the free-living nematode C. elegans, of which particularly T22D1.2 may be involved in tannin defense.
唾液富含脯氨酸蛋白（PRPs）是哺乳动物抵御单宁的一种常见防御机制。关于线虫中具有类似功能的PRPs的存在情况，相关报道较少，而且到目前为止，这些蛋白质或其编码基因均未进行功能鉴定。在秀丽隐杆线虫中，单宁处理线虫后，两个基因（clx-1和T22D1.2）被强烈诱导，它们都可能编码富含脯氨酸的蛋白质。因此，确认了这些基因可翻译成蛋白质，并对其表达模式进行了更详细的研究。特别发现，T22D1.2仅在经具有收敛特性的受试物质（尤其是单宁）处理的蠕虫中上调表达，而在任何其他应激源处理的蠕虫或未处理的对照组中均未观察到表达。与哺乳动物PRPs类似，在这两种相应蛋白质中都鉴定出了富含脯氨酸的重复序列。当T22D1.2在vit-5启动子下组成型表达时，单宁处理的蠕虫存活率增加，这支持了其在单宁防御中的潜在作用。然而，分别与野生型相比，clx-1和T22D1.2基因敲除突变体未观察到差异。在本研究中，为自由生活的线虫秀丽隐杆线虫中存在富含脯氨酸的重复蛋白质提供了证据，其中特别是T22D1.2可能参与单宁防御。
