519 / 2019-03-01 22:24:32

Transcriptomic analysis of shoot apical meristem cell types in Arabidopsis revealed markers for endoreduplication in differentiating cells

SAM, Arabidopsis, stem cells, differentiation, endoreduplication

Growth and Development > Growth and Development

The above ground organs of the plant are formed from the specialized tissue called shoot apical meristem (SAM). The cells in the mersitem maintain a balance between the cell proliferation and differentiation in response to underlying signals. The shoot apical meristem (SAM) is organized into layers (L1–L3) and zones. The stem cells reside at the centre, differentiating cells at the periphery and niche cells in the rib zone. Molecular control of cell cycle may play an important role in cell proliferation of shoot apical meristem. In the present study, we have shown for the first time that the different layers of SAM show distinct rate of mitotic division. This asynchrony can be reflected at the level of cell cycle gene transcription. In spite of diploid nature of shoot, the differences in cell cycle phases and in transcript expression of cell cycle regulatory genes was observed through Illumina Hiseq 2500 in florescent activated cell sorted (FACS) SAM cell types. CYCLIND3;1 was found to be only cyclin which showed more than 3 fold upregulation in stem cells compared to differentiated cells and kip related protein (KRP3) was the only cell cycle inhibitor that showed the differential expression in the transient differentiating cells, early cells of sepals, petals whose overexpression led to the endoreduplicated shoot, sepals, petals. It can have a future implication in delaying the differentiation and increase the stay green phenotype in plants