Faculty Opinions recommendation of Plant-Specific Histone Deacetylases HDT1/2 Regulate GIBBERELLIN 2-OXIDASE2 Expression to Control Arabidopsis Root Meristem Cell Number.

Rice (Oryza sativa L.) seedlings grown under nitrogen (N) deficiency conditions show a foraging response characterized by increased root length. However, the mechanism underlying this developmental plasticity is still poorly understood. In this study, the mechanism by which N deficiency influences rice seminal root growth was investigated. The results demonstrated that compared with the control (1 mM N) treatment, N deficiency treatments strongly promoted seminal root growth. However, the N deficiency-induced growth was negated by the application of zeatin, which is a type of cytokinin (CK). Moreover, the promotion of rice seminal root growth was correlated with a decrease in CK content, which was due to the N deficiency-mediated inhibition of CK biosynthesis through the down-regulation of CK biosynthesis genes and an enhancement of CK degradation through the up-regulation of CK degradation genes. In addition, the N deficiency-induced decrease in CK content not only enhanced the root meristem cell proliferation rate by increasing the meristem cell number via the down-regulation of OsIAA3 and up-regulation of root-expressed OsPLTs, but also promoted root cell elongation by up-regulating cell elongation-related genes, including root-specific OsXTHs and OsEXPs. Taken together, our data suggest that an N deficiency-induced decrease in CK content promotes the seminal root growth of rice seedlings by promoting root meristem cell proliferation and cell elongation.

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Contribution to the Understanding of the Mechanism of Cytokinesis In Plant Cells: the Action of Deoxyguanosine On the Kinetics of A Root Meristem Cell Population

Cell Proliferation ◽

10.1111/j.1365-2184.1978.tb00824.x ◽

1978 ◽

Vol 11 (5) ◽

pp. 519-527

Author(s):

M.-J. Lasselain ◽

C. Pareyre ◽

G. Deysson

Keyword(s):

Cell Population ◽

Root Meristem ◽

Plant Cells ◽

Meristem Cell ◽

Root Meristem Cell ◽

Kinetics Of

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Regulation of the stability of RGF1 receptor by the ubiquitin-specific proteases UBP12/UBP13 is critical for root meristem maintenance

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1714177115 ◽

2018 ◽

Vol 115 (5) ◽

pp. 1123-1128 ◽

Cited By ~ 19

Author(s):

Zhichao An ◽

Yuliang Liu ◽

Yang Ou ◽

Jia Li ◽

Baowen Zhang ◽

...

Keyword(s):

Root Meristem ◽

Peptide Hormone ◽

Cell Number ◽

Short Root ◽

Meristem Cell ◽

Meristem Development ◽

Positive Regulators ◽

Meristem Maintenance ◽

The Stability ◽

Close Homolog

ROOT MERISTEM GROWTH FACTOR (RGF) 1 is an important peptide hormone that regulates root growth. Upon binding to its receptor, RGFR1, RGF1 regulates the expression of two transcription factors, PLETHORA 1 and 2 (PLT1/2), to influence root meristem development. Here, we show that the ubiquitin-specific proteases UBP12 and UBP13 are positive regulators of root meristem development and that UBP13 interacts directly with RGF1 receptor (RGFR1) and its close homolog RGFR2. The ubp12,13 double-mutant root is completely insensitive to exogenous applied RGF1. Consistent with this result, RGF1-induced ubiquitination and turnover of RGFR1 protein were accelerated in ubp12,13-mutant plants but were delayed in transgenic plants overexpressing UBP13. Genetic analysis showed that PLT2 or RGFR1 overexpression partially rescued the short-root phenotype and the reduced cortical root meristem cell number in ubp12,13 plants. Together, our results demonstrate that UBP12/13 are regulators of the RGF1–RGFR1–PLT1/2 signaling pathway and that UBP12/13 can counteract RGF1-induced RGFR1 ubiquitination, stabilize RGFR1, and maintain root cell sensitivity to RGF1.

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