The leaf‐specific Catharanthus roseus alkaloid, vindoline, is the major bottleneck precursor in the production of scarce and costly anticancer bisindoles (vincristine and vinblastine). The final steps of its biosynthesis and storage occur in the laticifers. Earlier, we have shown that vindoline content is directly related to laticifer number. Pectin remodeling enzymes, like pectin methylesterase (PME), are known to be involved in laticifer development. A search in the croFGD yielded a leaf‐abundant CrPME isoform that co‐expressed with a few vindoline biosynthetic genes. Full‐length cloning, tissue‐specific expression profiling, and in silico analysis of CrPME were carried out. It was found to possess all the specific characteristics of a typical plant PME. Transient silencing (through VIGS) and overexpression of CrPME in C. roseus indicated a direct relationship between its expression and vindoline content. Comparative analysis of transcript abundance and enzyme activity in three familial C. roseus genotypes differing significantly in their vindoline content and laticifer count (CIM‐Sushil > Dhawal > Nirmal) also corroborated the positive relationship of CrPME expression with vindoline content. This study highlights the possible role of CrPME, a cell wall remodeling enzyme, in modulating laticifer‐associated secondary metabolism.

中文翻译：

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CrPME 的表征表明其在确定长春花叶中文多灵积累方面的可能作用

叶特异性长春花生物碱文多林是生产稀缺且昂贵的抗癌双吲哚（长春新碱和长春花碱）的主要瓶颈前体。其生物合成和储存的最后步骤发生在乳管中。早些时候，我们已经证明文多灵含量与乳管数量直接相关。果胶重塑酶，如果胶甲酯酶 (PME)，已知参与乳管发育。 croFGD 中的搜索产生了丰富的叶子肌醇PME与一些文多林生物合成基因共表达的亚型。全长克隆、组织特异性表达谱和计算机模拟分析肌醇PME进行了。人们发现它具有典型植物 PME 的所有特定特征。短暂沉默（通过 VIGS）和过度表达肌醇PME在玫瑰色念珠菌表明其表达与文多灵含量之间存在直接关系。三个家系转录本丰度和酶活性的比较分析玫瑰色念珠菌文多灵含量和乳汁计数显着差异的基因型（CIM-Sushil > Dhawal > Nirmal）也证实了 CrPME 表达与文多灵含量的正相关关系。这项研究强调了 CrPME（一种细胞壁重塑酶）在调节乳管相关次级代谢中的可能作用。