The ROOT MERISTEMLESS1/CADMIUM SENSITIVE2 gene defines a glutathione-dependent pathway involved in initiation and maintenance of cell division during post-embryonic root development

Oriented cell division is one mechanism progenitor cells use during development and to maintain tissue homeostasis. Common to most cell types is the asymmetric establishment and regulation of cortical NuMA-dynein complexes that position the mitotic spindle. Here, we discover that HMMR acts at centrosomes in a PLK1-dependent pathway that locates active Ran and modulates the cortical localization of NuMA-dynein complexes to correct mispositioned spindles. This pathway was discovered through the creation and analysis of Hmmr-knockout mice, which suffer neonatal lethality with defective neural development and pleiotropic phenotypes in multiple tissues. HMMR over-expression in immortalized cancer cells induces phenotypes consistent with an increase in active Ran including defects in spindle orientation. These data identify an essential role for HMMR in the PLK1-dependent regulatory pathway that orients progenitor cell division and supports neural development.

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Repression of Apical Homeobox Genes Is Required for Embryonic Root Development in Arabidopsis

Current Biology ◽

10.1016/j.cub.2009.06.070 ◽

2009 ◽

Vol 19 (17) ◽

pp. 1485-1490 ◽

Cited By ~ 64

Author(s):

Stephen P. Grigg ◽

Carla Galinha ◽

Noortje Kornet ◽

Claudia Canales ◽

Ben Scheres ◽

...

Keyword(s):

Root Development ◽

Homeobox Genes ◽

Embryonic Root

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Noncanonical auxin signaling regulates cell division pattern during lateral root development

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1910916116 ◽

2019 ◽

Vol 116 (42) ◽

pp. 21285-21290 ◽

Cited By ~ 9

Author(s):

Rongfeng Huang ◽

Rui Zheng ◽

Jun He ◽

Zimin Zhou ◽

Jiacheng Wang ◽

...

Keyword(s):

Cell Division ◽

Root Development ◽

Lateral Root ◽

Control Cell ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Auxin Signaling ◽

Lateral Root Development ◽

Division Pattern ◽

Mitogen Activated Protein

In both plants and animals, multiple cellular processes must be orchestrated to ensure proper organogenesis. The cell division patterns control the shape of growing organs, yet how they are precisely determined and coordinated is poorly understood. In plants, the distribution of the phytohormone auxin is tightly linked to organogenesis, including lateral root (LR) development. Nevertheless, how auxin regulates cell division pattern during lateral root development remains elusive. Here, we report that auxin activates Mitogen-Activated Protein Kinase (MAPK) signaling via transmembrane kinases (TMKs) to control cell division pattern during lateral root development. Both TMK1/4 and MKK4/5-MPK3/6 pathways are required to properly orient cell divisions, which ultimately determine lateral root development in response to auxin. We show that TMKs directly and specifically interact with and phosphorylate MKK4/5, which is required for auxin to activate MKK4/5-MPK3/6 signaling. Our data suggest that TMK-mediated noncanonical auxin signaling is required to regulate cell division pattern and connect auxin signaling to MAPK signaling, which are both essential for plant development.

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Discussion meeting on growth factors opening address

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1937.0068 ◽

1937 ◽

Vol 124 (834) ◽

pp. 1-13 ◽

Cited By ~ 5

Keyword(s):

Growth Factors ◽

Cell Division ◽

Plant Growth ◽

Plant Cell ◽

Root Development ◽

Plant Hormones ◽

Cell Elongation ◽

Plant Cells ◽

Opening Address ◽

Definite Proof

The growth of a plant cell may be separated schematically into the following stages: cell division, plasmatic growth and cell elongation. The definite proof that the growth of plant cells is regulated by plant hormones has first been found for the process of cell elongation. The term auxins is used to designate these hormones. The function of auxins in plants is not limited to cell elongation. Botanical investigations have shown that they also play a role in phototropism and geotropism, that they stimulate root development, induce cambial growth and prevent premature outgrowth of axillary buds. Auxins therefore regulate plant growth in many ways.

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