Colette A Ten Hove

Wageningen University, Wageningen, Gelderland, Netherlands

Are you Colette A Ten Hove?

Claim your profile

Publications (10)59.69 Total impact

  • Colette A Ten Hove, Kuan-Ju Lu, Dolf Weijers
    [Show abstract] [Hide abstract]
    ABSTRACT: Embryogenesis is the beginning of plant development, yet the cell fate decisions and patterning steps that occur during this time are reiterated during development to build the post-embryonic architecture. In Arabidopsis, embryogenesis follows a simple and predictable pattern, making it an ideal model with which to understand how cellular and tissue developmental processes are controlled. Here, we review the early stages of Arabidopsis embryogenesis, focusing on the globular stage, during which time stem cells are first specified and all major tissues obtain their identities. We discuss four different aspects of development: the formation of outer versus inner layers; the specification of vascular and ground tissues; the determination of shoot and root domains; and the establishment of the first stem cells. © 2015. Published by The Company of Biologists Ltd.
    Development 02/2015; 142(3):420-430. DOI:10.1242/dev.111500 · 6.27 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The root meristem (RM) is a fundamental structure that is responsible for postembryonic root growth. The RM contains the quiescent center (QC), stem cells and frequently dividing meristematic cells, in which the timing and the frequency of cell division are tightly regulated. In Arabidopsis thaliana, several gain-of-function analyses have demonstrated that peptide ligands of the CLAVATA3 (CLV3)/EMBRYO SURROUNDING REGION-RELATED (CLE) family are important for maintaining RM size. Here, we demonstrate that a plant U-box E3 ubiquitin ligase, PUB4, is a novel downstream component of CLV3/CLE signaling in the RM. Mutations in PUB4 reduced the inhibitory effect of exogenous CLV3/CLE peptide on root cell proliferation and columella stem cell maintenance. Moreover, pub4 mutants grown without exogenous CLV3/CLE peptide exhibited characteristic phenotypes in the RM, such as enhanced root growth, increased number of cortex/endodermis stem cells and decreased number of columella layers. Our phenotypic and gene expression analyses indicated that PUB4 promotes expression of a cell cycle regulatory gene, CYCD6;1, and regulates formative periclinal asymmetric cell divisions in endodermis and cortex/endodermis initial daughters. These data suggest that PUB4 functions as a global regulator of cell proliferation and the timing of asymmetric cell division that are important for final root architecture. © 2015. Published by The Company of Biologists Ltd.
    Development 02/2015; 142(3):444-53. DOI:10.1242/dev.113167 · 6.27 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Brassinosteroid (BR) signaling is essential for plant growth and development. In Arabidopsis (Arabidopsis thaliana), BRs are perceived by the BRASSINOSTEROID INSENSITIVE1 (BRI1) receptor. Root growth and hypocotyl elongation are convenient downstream physiological outputs of BR signaling. A computational approach was employed to predict root growth solely on the basis of BRI1 receptor activity. The developed mathematical model predicts that during normal root growth, few receptors are occupied with ligand. The model faithfully predicts root growth, as observed in bri1 loss-of-function mutants. For roots, it incorporates one stimulatory and two inhibitory modules, while for hypocotyls, a single inhibitory module is sufficient. Root growth as observed when BRI1 is overexpressed can only be predicted assuming that a decrease occurred in the BRI1 half-maximum response values. Root growth appears highly sensitive to variation in BR concentration and much less to reduction in BRI1 receptor level, suggesting that regulation occurs primarily by ligand availability and biochemical activity.
    Plant physiology 07/2012; 160(1):523-32. DOI:10.1104/pp.112.200105 · 7.39 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Receptor-like kinases (RLKs) constitute a large family of signal perception molecules in Arabidopsis. The largest group of RLKs is the leucine-rich repeat (LRR) class that has been described to function in development and defense. Of these, CLAVATA1 (CLV1) and ERECTA (ER) receptors function in maintaining shoot meristem homeostasis and organ growth, but LRR RLKs with similar function in the root remain unknown. For the interaction of Arabidopsis with the oomycete pathogen Hyaloperonospora arabidopsidis the involvement of LRR RLKs has not been demonstrated. A set of homozygous T-DNA insertion lines mutated in LRR RLKs was investigated to assess the potential role of these receptors in root meristem maintenance and compatibility. One mutant line, rlk902, was discovered that showed both reduced root growth and resistance to downy mildew in a recessive manner. The phenotypes of this mutated line could not be rescued by complementation, but are nevertheless linked to the T-DNA insertion. Microarray studies showed that gene expression spanning a region of approximately 84 kb upstream of the mutated gene was downregulated. The results suggest T-DNA mediated trans-repression of multiple genes upstream of the RLK902 locus links both phenotypes.
    PLoS ONE 04/2011; 6(4):e19028. DOI:10.1371/journal.pone.0019028 · 3.53 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Leucine-rich repeat receptor-like protein kinases (LRR RLKs) represent the largest group of Arabidopsis RLKs with approximately 235 members. A minority of these LRR RLKs have been assigned to diverse roles in development, pathogen resistance and hormone perception. Using a reverse genetics approach, a collection of homozygous T-DNA insertion lines for 69 root expressed LRR RLK genes was screened for root developmental defects and altered response after exposure to environmental, hormonal/chemical and abiotic stress. The obtained data demonstrate that LRR RLKs play a role in a wide variety of signal transduction pathways related to hormone and abiotic stress responses. The described collection of T-DNA insertion mutants provides a valuable tool for future research into the function of LRR RLK genes.
    Plant Molecular Biology 03/2011; 76(1-2):69-83. DOI:10.1007/s11103-011-9769-x · 4.07 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cell divisions generating daughter cells different in size, shape, identity, and function are indispensable for many developmental processes including fate specification, tissue patterning, and self-renewal. In animals and yeast, perturbations in factors required for well-described asymmetric cell divisions generally yield cells of equal fate. Here we report on SCHIZORIZA (SCZ), a single nuclear factor with homology to heat-shock transcription factors that controls the separation of cell fate in a set of stem cells generating different root tissues: root cap, epidermis, cortex, and endodermis. Loss-of-function, expression, and reconstitution experiments indicate that SCZ acts mainly from within its cortical expression domain in the stem cell niche, exerting both autonomous and nonautonomous effects to specify cortex identity and control the separation of cell fates in surrounding layers. Thus, SCZ defines a novel pathway for asymmetric cell division in plants.
    Current biology: CB 02/2010; 20(5):452-7. DOI:10.1016/j.cub.2010.01.018 · 10.99 Impact Factor
  • Source
    C.A. ten Hove
    [Show abstract] [Hide abstract]
    ABSTRACT: Asymmetric cell division is an essential and universal mechanism for generating diversity and pattern in multicellular organisms. Divisions generating daughter cells different in size, shape, identity and function are fundamental to many developmental processes including fate specification, tissue patterning and self-renewal. It is hypothesized that the angiosperm root meristem has evolved from the shoot apical meristem. Presumably, this is the outcome of the plants adaptation to changing environmental conditions. Accordingly, key gene network motifs present in the shoot have been found to be important in the development and regulation of the root meristem, such as peptide ligands and their receptors. In this thesis Arabidopsis root patterning and meristem maintenance has been investigated using forward and reverse genetics approaches. I describe the identification and analysis of SCHIZORIZA (SCZ). SCZ encodes a member of the family of heat shock transcription factors, albeit one that appears to be recruited for development instead of stress signaling. The pleiotropic effects of the scz mutation define the existence of a novel mechanism for patterning cell identity in the Arabidopsis root. SCZ acts in a parallel pathway with SHR/SCR to specify the root stem cell niche in the early embryo. Overexpression of CLE family peptides restricts the size of both the shoot and root meristem, suggesting that signaling pathways involved in shoot and root meristem maintenance are conserved. An activation tagging screen was performed on transgenic plants ectopically expressing CLE19 in the root meristem, aimed to identify new components of a root CLE signaling pathway. A recessive mutant, sol3, was isolated, which suppresses the CLE19 overexpression phenotype. SOL3 has a dual role in the root controlling growth and formative cell divisions. Using a reverse genetics approach I established and analyzed a collection of homozygous T-DNA insertion lines for 69 leucine-rich repeat receptor-like kinases (LRR RLKs) for developmental and conditional phenotypes. Possibly due to genetic redundancy the functional loss-of-function studies revealed developmental phenotypes for only one mutant line, rlk902. T-DNA insertion mutants assayed for their response after exposure to environmental, hormonal/chemical and abiotic stress, reveal several novel conditional functions for a number of RLK genes. rlk902 mutants show both reduced root growth and resistance to the oomycete pathogen Hyaloperonospora arabidopsidis. These phenotypes are not caused by RLK902 inactivation but are linked to the T-DNA insertion. Microarray analysis revealed downregulated gene expression over an 84 kb region upstream of and including RLK902 in rlk902, putatively encompassing the causal gene(s). The identification of SCZ as factor involved in tissue specification and cell fate segregation provides a basis for future research into mechanisms of asymmetric division. Work on CLE ligand signaling identified SOL3 as a factor controlling root growth and formative divisions and the LRR RLK reverse genetics indicated the existence of extensive cross talk and signal integration among different RLK signaling pathways in the Arabidopsis root. A challenge for the future will be to integrate these results with signaling networks for root patterning and growth.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Lateral organ position along roots and shoots largely determines plant architecture, and depends on auxin distribution patterns. Determination of the underlying patterning mechanisms has hitherto been complicated because they operate during growth and division. Here, we show by experiments and computational modeling that curvature of the Arabidopsis root influences cell sizes, which, together with tissue properties that determine auxin transport, induces higher auxin levels in the pericycle cells on the outside of the curve. The abundance and position of the auxin transporters restricts this response to the zone competent for lateral root formation. The auxin import facilitator, AUX1, is up-regulated by auxin, resulting in additional local auxin import, thus creating a new auxin maximum that triggers organ formation. Longitudinal spacing of lateral roots is modulated by PIN proteins that promote auxin efflux, and pin2,3,7 triple mutants show impaired lateral inhibition. Thus, lateral root patterning combines a trigger, such as cell size difference due to bending, with a self-organizing system that mediates alterations in auxin transport.
    PLoS Biology 01/2009; 6(12):e307. DOI:10.1371/journal.pbio.0060307 · 11.77 Impact Factor
  • Colette A Ten Hove, Renze Heidstra
    [Show abstract] [Hide abstract]
    ABSTRACT: Asymmetric cell division generates cell types with different fates. Recent studies have improved our understanding of the molecular mechanisms involved in asymmetric cell division in Arabidopsis thaliana. Genetic approaches have identified candidate intrinsic factors and signaling components that mediate extrinsic cues. WOX genes appear to be putative intrinsic determinants acting in early embryonic asymmetric divisions. A non-canonical mechanism involving specific SHORT ROOT (SHR)-SCARECROW (SCR) nuclear complexes is implicated in ground tissue asymmetric divisions. Asymmetric stem cell division requires extrinsic organizer signaling, whereas the involvement of intrinsic stem cell segregants is unknown. Finally, new studies on stomatal development have identified several intrinsic acting factors that specify cell fate and an extrinsic signaling cascade that controls the number and plane of asymmetric divisions.
    Current Opinion in Plant Biology 03/2008; 11(1):34-41. DOI:10.1016/j.pbi.2007.11.001 · 9.39 Impact Factor
  • Source