Galibina Natalia A, Tarelkina Tatiana V, Chirva Olga V, Moshchenskaya Yulia L, Nikerova Kseniya M, Ivanova Diana S, Semenova Ludmila I, Serkova Aleksandra A, Novitskaya Ludmila L
Forest Research Institute, Karelian Research Centre of the Russian Academy of Sciences, 11 Pushkinskaya St., Petrozavodsk 185910, Russia.
Plants (Basel). 2021 Aug 2;10(8):1593. doi: 10.3390/plants10081593.
Silver birch ( Roth) is an economically important species in Northern Europe. The current research focused on the molecular background of different xylogenesis scenarios in the birch trunks. The study objects were two forms of silver birch, silver birch trees, and Karelian birch trees; the latter form is characterized by the formation of two types of wood, non-figured (straight-grained) and figured, respectively, while it is currently not clear which factors cause this difference. We identified // genes that regulate secondary cell wall biosynthesis in the birch genome and revealed differences in their expression in association with the formation of xylem with different ratios of structural elements. High expression levels of accompanied differentiation of the type of xylem which is characteristic of the species. At the same time, the appearance of figured wood was accompanied by the low expression levels of the genes and increased levels of expression of and genes. We identified as a crucial regulator of auxin-dependent vascular patterning and its direct target-. A decrease in the level expression in differentiating xylem was a specific characteristic of both Karelian birch with figured and non-figured wood. Decreased level expression in non-figured trees accompanied by decreased and expression levels compared to figured Karelian birch trees. According to the results obtained, we suggested silver birch forms differing in wood anatomy as valuable objects in studying the regulation of xylogenesis.
银桦（Roth）是北欧一种具有重要经济价值的树种。当前的研究聚焦于桦树树干中不同木质形成过程的分子背景。研究对象为两种银桦形态，即银桦树和卡累利阿桦树；后一种形态的特点是分别形成两种类型的木材，即无花纹（直纹理）木材和有花纹木材，而目前尚不清楚是哪些因素导致了这种差异。我们在桦树基因组中鉴定出了调控次生细胞壁生物合成的基因，并揭示了它们的表达差异与具有不同结构元素比例的木质部形成之间的关联。高表达水平伴随着该物种特有的木质部类型的分化。同时，有花纹木材的出现伴随着某些基因的低表达水平以及另外一些基因表达水平的升高。我们鉴定出某基因是生长素依赖性维管束模式形成的关键调节因子及其直接靶点。在分化的木质部中该基因表达水平的降低是具有有花纹和无花纹木材的卡累利阿桦树的一个特定特征。与有花纹的卡累利阿桦树相比，无花纹树木中该基因表达水平的降低伴随着另外两个基因表达水平的降低。根据所获得的结果，我们认为在木材解剖结构上存在差异的银桦形态是研究木质形成调控的有价值对象。
