Single Cell Map of Rice Root Tissue Drawn

Recently, Gu Xiaofeng's team and collaborators from the Institute of Biotechnology, Chinese Academy of Agricultural Sciences (CAAS) have mapped the first single-cell resolution transcriptome map of rice root tissue, which provides a new way to study plant cell type specialization, function, and evolution. The results were published in the international academic journal Molecular Plant.

In the whole process of plant life, the root tip is developing continuously. The formed roots absorb water and mineral elements from the soil, participate in the interaction between plant and biological or abiotic signals, and play the role of fixing the plant. However, little is known about the molecular mechanism of plant root development and interaction with the environment. Single-cell transcriptome sequencing and analysis were performed on 10968 and 12564 root tip cells of Japonica Rice nip (Geng) and Indica rice 93-11 (Xian). Eight cell types were identified. Functional enrichment analysis of the differentially expressed genes of nip and 93-11 showed that most of the genes were related to environmental response, and the response mechanisms of different rice subspecies were different when they were stimulated by the external environment.

The researchers then conducted a time-dependent analysis on the single-cell data of rice, and drew the development trajectory of the outermost cells of the root. The single-cell trajectory from the two cultivars showed a highly consistent time-dependent sequence, indicating the conservatism of the development trajectory among different subspecies. This is the first time to analyze the evolution of plant tissues and organs at the single-cell level. It is found that the transcriptome of most cell types in Arabidopsis and rice are quite different, only the root hair cells have a high correlation. Thus, the monocotyledons/dicotyledons can be explained from the single-cell level Genetic basis of root type differentiation.

Reference

Qing Liu, et al. Transcriptional Landscape of Rice Roots at the Single-Cell Resolution. Mol Plant. 2020 Dec 19; S1674-2052(20)30445-7. doi: 10.1016/j.molp.2020.12.014.