Sequencing historical RNA: unrealized potential to increase understanding of the plant tree of life.

Recent studies have demonstrated that it is a misconception that transcriptome sequencing requires tissue preserved at ultracold temperatures. Here, we outline the potential origins of this misconception and its possible role in biasing the geographic distribution of published plant transcriptomes. We highlight the importance of ensuring diverse sampling by providing an overview of the questions that transcriptomes can answer about the forces shaping the plant tree of life. We discuss how broadening transcriptome sequencing to include existing specimens will allow the field to grow and more fully utilize biological collections. We hope this article encourages the expansion of the current trend in 'herbariomics' research to include whole-transcriptome sequencing of historical RNA.