D'Amelia Vincenzo, Piccinelli Anna Lisa, Docimo Teresa, Cirillo Valerio, Maggio Albino, Chiaiese Pasquale, Possenti Marco, D'Orso Fabio, Staiti Annalisa, Aversano Riccardo, Carputo Domenico
Department of Agricultural Sciences, University of Naples Federico II, Piazza Carlo di Borbone 1, Portici 80055, Italy.
Department of Pharmacy, University of Salerno, Via Giovanni Paolo, II 132, Fisciano 84084, Italy.
Plant Cell Physiol. 2025 Jul 24;66(6):878-889. doi: 10.1093/pcp/pcaf028.
Events of duplication and neo/subfunctionalization have significantly expanded the functional roles of R2R3 myeloblastosis (MYB) transcription factors in plants. In a previous study, we demonstrated that two paralogous R2R3 MYBs from Solanum tuberosum and S. commersonii, AN1 and AN2, respectively, induce anthocyanin pigmentation to varying extents when transiently overexpressed. However, questions related to the distinct functions of these genes remained unanswered. In this study, we further investigated these genes by comparing transgenic tobacco plants that constitutively overexpress AN1 and AN2. We observed differences between AN1 and AN2 that not only influenced plant pigmentation but also impacted the structural features of vascular tissues. Both genes promoted the accumulation of phenolamides; however, AN1 showed a stronger capacity to regulate the phenylpropanoid pathway. In addition, our results suggest a potential role for AN2 in regulating additional biological processes potentially involved in vascular development, as indicated by the GUS promoter localization study. Collectively, these results shed new light on the potentially ancestral functions of these R2R3 MYB genes, extending their known impact beyond anthocyanin biosynthesis.
基因复制和新功能化/亚功能化事件显著扩展了R2R3髓细胞白血病病毒原癌基因（MYB）转录因子在植物中的功能作用。在之前的一项研究中，我们证明了来自马铃薯和野生马铃薯的两个同源R2R3 MYB基因，分别为AN1和AN2，在瞬时过表达时会不同程度地诱导花青素色素沉着。然而，与这些基因独特功能相关的问题仍未得到解答。在本研究中，我们通过比较组成型过表达AN1和AN2的转基因烟草植株，进一步研究了这些基因。我们观察到AN1和AN2之间的差异，这些差异不仅影响植物色素沉着，还影响维管组织的结构特征。两个基因都促进了酚酰胺的积累；然而，AN1在调节苯丙烷途径方面表现出更强的能力。此外，我们的结果表明，GUS启动子定位研究表明，AN2在调节可能参与维管发育的其他生物学过程中具有潜在作用。总的来说，这些结果为这些R2R3 MYB基因的潜在祖先功能提供了新的线索，将它们已知的影响扩展到花青素生物合成之外。
