Klemm Paul, Christ Marvin, Altegoer Florian, Freitag Johannes, Bange Gert, Lechner Marcus
Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany.
Institute of Microbiology, Heinrich Heine University Dusseldorf, Düsseldorf, Germany.
Front Plant Sci. 2022 Dec 22;13:1034708. doi: 10.3389/fpls.2022.1034708. eCollection 2022.
Crop diseases caused by pathogens critically affect global food security and plant ecology. Pathogens are well adapted to their host plants and have developed sophisticated mechanisms allowing successful colonization. Plants in turn have taken measures to counteract pathogen attacks resulting in an evolutionary arms race. Recent studies provided mechanistic insights into how two plant Kiwellin proteins from mitigate the activity of the chorismate mutase Cmu1, a virulence factor secreted by the fungal pathogen during maize infection. Formerly identified as human allergens in kiwifruit, the biological function of Kiwellins is apparently linked to plant defense. We combined the analysis of proteome data with structural predictions to obtain a holistic overview of the Kiwellin protein family, that is subdivided into proteins with and without a N-terminal kissper domain. We found that Kiwellins are evolutionarily conserved in various plant species. At median five Kiwellin paralogs are encoded in each plant genome. Structural predictions revealed that Barwin-like proteins and Kiwellins cannot be discriminated purely at the sequence level. Our data shows that Kiwellins emerged in land plants (embryophyta) and are not present in fungi as suggested earlier. They evolved three major duplication events that lead to clearly distinguishable subfamilies. We introduce a systematic Kiwellin nomenclature based on a detailed evolutionary reconstruction of this protein family. A meta-analysis of publicly available transcriptome data demonstrated that Kiwellins can be differentially regulated upon the interaction of plants with pathogens but also with symbionts. Furthermore, significant differences in Kiwellin expression levels dependent on tissues and cultivars were observed. In summary, our study sheds light on the evolution and regulation of a large protein family and provides a framework for a more detailed understanding of the molecular functions of Kiwellins.
由病原体引起的作物病害严重影响全球粮食安全和植物生态。病原体对其宿主植物具有良好的适应性，并已进化出复杂的机制以实现成功定殖。反过来，植物也采取了措施来对抗病原体的攻击，从而形成了一场进化军备竞赛。最近的研究对来自玉米的两种植物基维林蛋白如何减轻分支酸变位酶Cmu1的活性提供了机制上的见解，Cmu1是真菌病原体在感染玉米期间分泌的一种毒力因子。基维林蛋白以前在猕猴桃中被鉴定为人类过敏原，其生物学功能显然与植物防御有关。我们将蛋白质组数据分析与结构预测相结合，以全面了解基维林蛋白家族，该家族可细分为具有和不具有N端kisper结构域的蛋白质。我们发现基维林蛋白在各种植物物种中具有进化保守性。每个植物基因组中平均编码五个基维林旁系同源物。结构预测表明，类Barwin蛋白和基维林蛋白不能仅在序列水平上进行区分。我们的数据表明，基维林蛋白出现在陆地植物（胚植物）中，而不像早期所认为的那样存在于真菌中。它们通过三次主要的复制事件进化，导致明显可区分的亚家族。我们基于对该蛋白家族的详细进化重建引入了一种系统的基维林命名法。对公开可用转录组数据的荟萃分析表明，基维林蛋白在植物与病原体以及与共生体相互作用时可受到差异调节。此外，还观察到基维林蛋白表达水平在不同组织和品种之间存在显著差异。总之，我们的研究揭示了一个大型蛋白家族的进化和调控，并为更详细地了解基维林蛋白的分子功能提供了一个框架。
