Insight into the central and nodal cells transcriptome of the streptophyte green alga Chara braunii S276

Abstract

Chara braunii is an emerging model system for streptophyte terrestrialization and early land plant evolution. In this study, tissue containing nodal cells was prepared under the stereomicroscope and an RNA-seq dataset generated and compared to transcriptome data from whole plantlets. In both samples, transcript coverage was high for genes encoding ribosomal proteins and a homolog of the putative PAX3- and PAX7-binding protein 1. Gene ontology-based functional assignments revealed for the nodal cell sample main upregulated molecular functions related to protein binding, nucleic acid binding and DNA binding. Looking at specific genes, several signalling-related genes and genes encoding sugar-metabolizing enzymes were found to be expressed at a higher level in the nodal cell sample, while photosynthesis-and chloroplast-related genes were expressed at a comparatively lower level. We detected the transcription of 21 different genes encoding DUF4360-containing cysteine-rich proteins. The data contribute to the growing understanding of charophyte developmental genetics by providing a first insight into the transcriptome composition of Chara central and nodal cells.