The study demonstrates that RNA extracted from herbarium specimens can be used to generate high‑quality transcriptomes, comparable to those from fresh or silica‑dried samples. By assembling and comparing transcriptomes across specimen types, the authors validated a plant immune receptor synthesized from a 1956 collection, proving archival RNA’s utility for functional genomics. These findings challenge the prevailing view that herbarium RNA is unsuitable for transcriptomic analyses.

The study mapped the subcellular localization of isoprenoid biosynthetic enzymes in Marchantia polymorpha, confirming most predictions and identifying oil body cells as primary sites of terpene synthesis. Overexpression and CRISPR knockout of the ABC transporter ABCG1 revealed its essential role in retaining sesquiterpenes within oil bodies, while attempts to boost heterologous diterpene and triterpene production in oil bodies did not increase yields.