Search

Your search keyword '"Willemsen, V.A."' showing total 11 results
Start Over Author "Willemsen, V.A."
11 results on '"Willemsen, V.A."'

1. Cis-regulatory PLETHORA promoter elements directing root and nodule expression are conserved between Arabidopsis thaliana and Medicago truncatula

Author

Franssen, H.G.J.M., Kulikova, O., Willemsen, V.A., Heidstra, R., Franssen, H.G.J.M., Kulikova, O., Willemsen, V.A., and Heidstra, R.

Abstract

Nodules are unique organs formed on roots of legumes by soil-borne bacteria, collectively known as rhizobium. Recently, we have shown that orthologs of the AINTEGUMENTA-like (AIL) AP2 transcription factors PLETHORA (PLT) 1 to 4, that redundantly regulate Arabidopsis thaliana root development are involved in root and nodule growth in Medicago truncatula. Hence, it is conceivable that rhizobium has co-opted these genes for nodule development. Whether this co-option requires the presence of specific cis-elements in the promoters and/or specialization of PLT protein function is not clear. Here, we analyzed the qualitative expression patterns of the Arabidopsis PLT1 to 4 promoters in Medicago roots and nodules and compared these with the described expression patterns of the Medicago PLT genes. Our studies reveal that the expression patterns of the investigated promoters and their Medicago orthologs are very similar, indicating that at least all cis-elements regulating spatial PLT expression are conserved among the Arabidopsis and Medicago PLT1 to 4 promoters.

Published
2017

3. The PIN auxin efflux facilitator network controls growth and patterning in Arabidopsis roots

Author

Blilou, I., Xu, J., Wildwater, M., Willemsen, V.A., Paponov, I., Friml, J., Heidstra, R., Aida, M., Palme, K., Scheres, B.J.G., Pattern and polarity in Arabidopsis root development, Universiteit Utrecht, and Dep Biologie

Subjects
Biologie/Milieukunde (BIOL), International (English), fungi, food and beverages, Life sciences
Abstract

Local accumulation of the plant growth regulator auxin mediates pattern formation in Arabidopsis roots and influences outgrowth and development of lateral root- and shoot-derived primordia. However, it has remained unclear how auxin can simultaneously regulate patterning and organ outgrowth and how its distribution is stabilized in a primordium-specific manner. Here we show that five PIN genes collectively control auxin distribution to regulate cell division and cell expansion in the primary root. Furthermore, the joint action of these genes has an important role in pattern formation by focusing the auxin maximum and restricting the expression domain of PLETHORA (PLT) genes, major determinants for root stem cell specification. In turn, PLT genes are required for PIN gene transcription to stabilize the auxin maximum at the distal root tip. Our data reveal an interaction network of auxin transport facilitators and root fate determinants that control patterning and growth of the root primordium.

Published
2005

4. Mechanisms of pattern formation in plant embryogenesis

Author

Willemsen, V.A., Scheres, B.J.G., Pattern and polarity in Arabidopsis root development, Universiteit Utrecht, and Dep Biologie

Subjects
Biologie/Milieukunde (BIOL), International (English), Life sciences
Published
2004

5. The PLETHORA genes mediate patterning of the Arabidopsis root stem cell niche

Author

Aida, M., Beis, D., Heidstra, R., Willemsen, V.A., Blilou, I., Reis Galinha, C.I., Nussaume, L., Noh, Y.-S., Amasino, R., Scheres, B.J.G., Pattern and polarity in Arabidopsis root development, Universiteit Utrecht, and Dep Biologie

Subjects
Biologie/Milieukunde (BIOL), International (English), Life sciences
Published
2004

6. Cell polarity and PIN protein positioning in Arabidopsis requie STEROL METHYLTRANSFERASE1 function

Author

Willemsen, V.A., Friml, J., Grebe, M., van den Toorn, Albert, Scheres, B.J.G., Pattern and polarity in Arabidopsis root development, Dep Biologie, and Sub Moleculair Genetics begr. 01-01-2014

Subjects
Biologie/Milieukunde (BIOL), Life sciences
Abstract

Plants have many polarized cell types, but relatively little is known about the mechanisms that establish polarity. The orc mutant was identified originally by defects in root patterning, and positional cloning revealed that the affected gene encodes STEROL METHYLTRANSFERASE1, which is required for the appropriate synthesis and composition of major membrane sterols. smt1orc mutants displayed several conspicuous cell polarity defects. Columella root cap cells revealed perturbed polar positioning of different organelles, and in the smt1orc root epidermis, polar initiation of root hairs was more randomized. Polar auxin transport and expression of the auxin reporter DR5--glucuronidase were aberrant in smt1orc. Patterning defects in smt1orc resembled those observed in mutants of the PIN gene family of putative auxin efflux transporters. Consistently, the membrane localization of the PIN1 and PIN3 proteins was disturbed in smt1orc, whereas polar positioning of the influx carrier AUX1 appeared normal. Our results suggest that balanced sterol composition is a major requirement for cell polarity and auxin efflux in Arabidopsis.

Published
2003

7. PLETHORA proteins as dose-dependent master regulators of Arabidopsis root development

Author

Pattern and polarity in Arabidopsis root development, Dep Biologie, Reis Galinha, C.I., Hofhuis, H.F., Luijten, M., Willemsen, V.A., Blilou, I., Heidstra, R., Scheres, B.J.G., Pattern and polarity in Arabidopsis root development, Dep Biologie, Reis Galinha, C.I., Hofhuis, H.F., Luijten, M., Willemsen, V.A., Blilou, I., Heidstra, R., and Scheres, B.J.G.

Published
2007

8. The PIN auxin efflux facilitator network controls growth and patterning in Arabidopsis roots

Author

Pattern and polarity in Arabidopsis root development, Universiteit Utrecht, Dep Biologie, Blilou, I., Xu, J., Wildwater, M., Willemsen, V.A., Paponov, I., Friml, J., Heidstra, R., Aida, M., Palme, K., Scheres, B.J.G., Pattern and polarity in Arabidopsis root development, Universiteit Utrecht, Dep Biologie, Blilou, I., Xu, J., Wildwater, M., Willemsen, V.A., Paponov, I., Friml, J., Heidstra, R., Aida, M., Palme, K., and Scheres, B.J.G.

Published
2005

9. The PLETHORA genes mediate patterning of the Arabidopsis root stem cell niche

Author

Pattern and polarity in Arabidopsis root development, Universiteit Utrecht, Dep Biologie, Aida, M., Beis, D., Heidstra, R., Willemsen, V.A., Blilou, I., Reis Galinha, C.I., Nussaume, L., Noh, Y.-S., Amasino, R., Scheres, B.J.G., Pattern and polarity in Arabidopsis root development, Universiteit Utrecht, Dep Biologie, Aida, M., Beis, D., Heidstra, R., Willemsen, V.A., Blilou, I., Reis Galinha, C.I., Nussaume, L., Noh, Y.-S., Amasino, R., and Scheres, B.J.G.

Published
2004

10. Mechanisms of pattern formation in plant embryogenesis

Author

Pattern and polarity in Arabidopsis root development, Universiteit Utrecht, Dep Biologie, Willemsen, V.A., Scheres, B.J.G., Pattern and polarity in Arabidopsis root development, Universiteit Utrecht, Dep Biologie, Willemsen, V.A., and Scheres, B.J.G.

Published
2004

11. Cell polarity and PIN protein positioning in Arabidopsis requie STEROL METHYLTRANSFERASE1 function

Author

Pattern and polarity in Arabidopsis root development, Dep Biologie, Sub Moleculair Genetics begr. 01-01-2014, Willemsen, V.A., Friml, J., Grebe, M., van den Toorn, Albert, Scheres, B.J.G., Pattern and polarity in Arabidopsis root development, Dep Biologie, Sub Moleculair Genetics begr. 01-01-2014, Willemsen, V.A., Friml, J., Grebe, M., van den Toorn, Albert, and Scheres, B.J.G.

Published
2003

Catalog

Books, media, physical & digital resources
See catalog results