Identification and characterization of novel regulators of the Cell Cycle in Plants

COOLS, T.; DE VEYLDER, L; GOLDY, CAMILA; BENFEY, PN; RODRIGUEZ, RAMIRO E.; BREAKFIELD, NW; PALATNIK, JAVIER F.

Campos do Jordão

Simposio; VII Brazilian Symposium on Plant Molecular Genetics; 2019

Plant organ growth occurs through an initial stage of cell proliferation followed by cell expansion and differentiation. Therefore, the control of the cell cycle (CC) is critical to determine the magnitude and direction of plant organ growth. CC regulators have oscillating activities regulated by transcriptional and posttranscriptional mechanisms. For example, the E2F and MYB3R transcription factors (TF) are involved in controlling gene expression during the G1/S and G2/M transitions. Genomic studies indicated that only a subset of the genes with expression enriched at the G1/S or G2/M transitions are directly regulated by the E2F or MYB3R TFs, suggesting that other transcriptional regulators remain to be identified.To identify genes that control the CC we first analyzed the transcriptome of cells in G2/M obtained by Fluorescence Activated Cell Sorting of protoplasts prepared from roots expressing a GFP reporter of a mitotic cyclin. Analysis of these data yielded ca. 400 genes with expression enriched in G2/M, of which only a fraction has been previously described to be involved in the CC. Analysis of the remaining genes enabled us to identify new potential regulators of the CC, including ten transcription factors, enzymes involved in redox and calcium metabolism, motor proteins, etc. The initial characterization of some of these candidates, with special emphasis on the transcription factors identified, will be discussed.