Transcriptomic comparison between nickel hyperaccumulator and non-accumulator plant species from the Psychotria genus (Rubiacaeae) endemic from New Caledonia

The leaf transcriptome of the nickel hyperaccumulator Psychotria gabriellae (Rubiaceae) endemic from New Caledonia was compared to the closely related non-accumulator Psychotria semperflorens, living in sympatry with P. gabriellae in rain forest on serpentine soil, to identity differentially expressed genes potentially involved in Ni hyperaccumulation. Overall design: Leaves from 3 independant individual plants of Psychotria gabriellae and Psychotria semperflorens were collected in their natural environment. RNA of the 6 independant samples were extracted and sequenced using the Illumina paired-end sequencing technology. Reads from one individual plant per species were assembled de novo to generate transcriptome sequences. The transcriptome of P. gabriellae was used as a reference to compare the expression of genes in both species.

本研究以新喀里多尼亚特有镍超富集植物加布里埃莱九节（*Psychotria gabriellae*，茜草科Rubiaceae）的叶片转录组（transcriptome）为研究对象，将其与同域分布于蛇纹石土壤雨林中、亲缘关系相近的非镍富集物种宿花九节（*Psychotria semperflorens*）进行比较分析，旨在鉴定可能参与镍超富集过程的差异表达基因。
实验总体设计：从加布里埃莱九节与宿花九节各3株独立个体的自然生境中采集叶片样本。对6份独立样本的RNA进行提取，并采用Illumina双端测序技术（Illumina paired-end sequencing technology）完成测序。选取每个物种各1株个体的测序读段（reads）进行从头组装（de novo）以生成转录组序列。以加布里埃莱九节的转录组作为参考，对比分析两个物种的基因表达水平。