To obtain pdf copies of any of the publications either follow the indicated links or contact Dr. Geitmann.
Assembly of a simple scalable device for micromechanical testing of plant tissues
Bidhendi AJ, Zamil MS, Geitmann A (2020) Methods in Cell Biology
A detailed description of our custom built tensile tester is accompanied by considerations about the technical specifications of the components and an example of the device's application on onion epidermis.
Pectin and cellulose play important roles in plant tissue development. Robust experimental protocols for fluorescence visualization of these cell wall polysaccharides are essential for structural and developmental studies. Download author version.
Reimann R, Kah D, Mark C, Dettmer J, Reimann T, Gerum RC, Geitmann A, Fabry B, Dietrich P, Kost B. (2020) Plant Physiology, DOI: https://doi.org/10.1104/pp.19.01505
Pollen tubes in some plant species prefer growing through stiffened matrices, consistent with their in vivo behavior. We coined this behavior durotropism. First authors Delf Kah and Ronny Reimann are featured by Plantae.
Leaves come in all shapes, forms and functionalities. How different leaf shapes are formed is a fundamental developmental question and through modeling based on patio-temporal gene expression data we start understanding how the process works.
Plant Biomechanics - an interdisciplinary lens on plant biology
Geitmann A (2020) Botany 98: vii–viii
The 9th International Conference on Plant Biomechanics was held in Montreal, Canada. This editorial highlights the benefit of creating venues that provide the opportunity for representatives from different disciplines to meet, discuss, exchange, agree, disagree, and join forces for new collaborations.
Pectin chemistry and cellulose crystallinity govern pavement cell morphogenesis in a multi-step mechanism
Altartouri B, Bidhendi AJ, Tani T, Conrad C, Chebli Y, Liu N, Karunakaran C, Scarcelli G, Geitmann A (2019) Plant Physiolgoy 181: 127-141
Using polarized fluorescence microscopy combined with confocal laser scanning microscopy we reveal the spatio-temporal dynamics of cell wall polymers and microtubules associated with the morphogenetic process in the leaf epidermis. Brillouin microscopy is employed to demonstrate the effect on cell wall mechanical behavior.
The shaping of plant cells during differentiation is governed by the primary cell wall whose properties in turn are regulated by cytoskeletal dynamics. We used finite element modelling to identify the biomechanical principles underlying the morphogenesis of intricate shapes such as those in the leaf epidermis.
Geitmann A (editor) 2019. Journal of Experimental Botany, Vol 70, Issue 14. Special issue
This special issue on plant biomechanics arises from the 9th International Plant Biomechanics Conference held in Montreal, August 2018. The 16 articles exemplify the state-of-the-art of the field and are accompanied by an editorial.
Geitmann A, Niklas K, Speck T (2019) Journal of Experimental Botany 70: 3435-3438
This editorial introduces the history of plant biomechanics research, elaborates on the series of international conferences on the topic, delivers a tribute to late Professor Hanns-Christof Spatz, and summarizes the 16 articles in the special issue of the Journal of Experimental Botany.
Methods to quantify primary plant cell wall mechanics
Bidhendi AJ, Geitmann A (2019) Journal of Experimental Botany 70: 3615–3648
There are many ways to measure the mechanical properties of the primary plant cell wall, and how these numbers are interpreted needs to consider the caveats of each method. This review contains a glossary of plant biomechanics terms and a catalog of all the numbers for primary wall mechanics we were able to find in the literature.
Geometrical details matter for mechanical modeling of cell morphogenesis
Bidhendi AJ, Geitmann A. 2019. Developmental Cell 50: 117-125
Modeling biological processes is challenging and requires careful consideration of input parameters and assumptions. Here we show that modeling the morphogenesis of leaf epidermal cells needs to be done by considering the complete 3D geometry of the cell to account for relevant forces driving cell growth.
Plant AP180 N-Terminal Homolog (ANTH) proteins are involved in clathrin-dependent endocytosis during pollen tube growth in Arabidopsis thaliana
Kaneda M, Triplet van Oostende C, Chebli Y, Testerink C, Bednarek SY, Geitmann A. 2019. Plant and Cell Physiology 6: 1316–1330
Polarized cell growth in plants is maintained under the strict control and exquisitely choregraphed balance of exocytic and endocytic membrane trafficking. This paper investigates clathrin mediated endocytosis, cell wall assembly and morphogenesis in growing pollen tubes.
Growing pollen tubes have the capacity to invade and overcome the mechanical resistance of the pistillar tissues. We measured the force of single growing pollen tubes and assessed how physical contact with an obstacle alters the growth behavior.
Shedding of organs requires the orchestration of multiple cellular activities that ensure the separation and detachment of the organ as well as the protection of the fracture plane. This preview highlights a recent study that investigates the role of lignin deposition in the process.
Tensile testing of primary plant cells and tissues
Bidhendi AJ, Geitmann A. 2018. In: Plant Biomechanics - From Structure to Function at Multiple Scales. Geitmann A, Gril J (eds), Springer Verlag, pp 321-347
The predominant mechanical role of the primary cell wall lies in its ability to resist or conform to tensile forces. Assessing the tensile properties of the cell wall, therefore, is a fundamental feature from both biomechanics and mechanobiology perspectives. Here, we discuss tensile testing strategies for plant samples with primary cell walls.
Cameron C, Geitmann A. 2018. Current Opinion in Genetics & Development 51: 11-17
Through the recent advent of new technology and computational methods researchers have been able to study particular phenomena characterizing pollen tube growth such as oscillatory growth, invasive growth, and directional control.
A mechanosensitive Ca2+-channel activity is dependent on the developmental regulator DEK1
Tran D, Galletti R, Neumann ED, Dubois A, Sharif-Naeini R, Geitmann A, Frachisse J-M, Hamant O, Ingram GC. 2017. Nature Communications 8:1009
The Arabidopsis Defective Kernel 1 (DEK1) protein is essential for plant development beyond early embryogenesis. It is associated with a mechanically activated Ca2+ current suggesting that perception of mechanical stress plays a critical role in plant development.
Depletion of the mitotic kinase Cdc5p in Candida albicans results in the formation of elongated buds that switch to the hyphal fate over time in a Ume6p and Hgc1p-dependent manner
Glory A, Triplet-van Oostende C, Geitmann A, Bachewich C. 2017. Fungal Genetics & Biology 107:51-66
The fungal pathogen Candida albicans differentiates between yeast, hyphae and pseudohyphae in order to enhance survival in the human host and virulence. In order to clarify the nature of these growth forms, aspects of the polar growth machinery were investigated.
Vesicle dynamics during plant cytokinesis reveals distinct developmental phases
Triplet van Oostende C, Guillet D, Triplet T, Pandzic E, Wiseman PW, Geitmann A. 2017. Plant Physiology 174: 1544–1558
Exquisitely choreographed transport of vesicles is necessary to form the new cell plate separating daughter cells during mitosis. 4D confocal microscopy and spatio-temporal image correlation spectroscopy revealed distinct functional phases during cell plate formation - testimony to a highly optimized mechanism.
Zamil MS, Geitmann A. 2017. Physical Biology 14, 015004
The middle lamella glues plant cells together to form a tissue, but it has its own, distinct material properties. We only know rather little about this material and its mechanical properties. What we do know is summarized here.
Cellular growth in plants requires regulation of cell wall biochemistry
Chebli Y, Geitmann A. 2017. Current Opinion in Cell Biology 44: 28-35
Cell and organ morphogenesis in plants are regulated by the chemical structure and mechanical properties of the extracellular matrix, the cell wall. How the remodelling of this material is regulated to generate the morphological changes required during plant development is explored.
Microfluidics and MEMS (microelectromechanical systems)-based platforms for experimental analysis of pollen tube growth behavior and quantification of cell mechanical properties
Geitmann A. 2017. In: Obermeyer G, Feijó J (eds) Pollen Tube Tip Growth: From Biophysical Aspects to Systems Biology. Springer Verlag, pp 87-103
Microfluidic technology can be used for the micromanipulation of single cells. Clever engineering has allowed for the measurement of single cell forces and the quantitative determination of biomechanical parameters. How these techniques have been exploited to study growing pollen tubes is summarized in this chapter.
Control of cellular morphogenesis through intracellular trafficking
Rakusova H, Geitmann A. 2017. In: Obermeyer G, Feijó J (eds) Pollen Tube Tip Growth: From Biophysical Aspects to Systems Biology. Springer Verlag, pp 129-148
The pollen tube accomplishes invasive and directed behavior by manipulating the force and orientation of its cellular expansive growth. This in turn necessitates the orchestration ofits intracellular transport and secretory machinery. The molecular regulatory mechanisms involved in these processes are summarized in this contribution.
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Actuators acting without actin
Geitmann A. 2016. Cell 166:15-17
How do plant organs effect movement? Very differently from animal organs, that is for sure! Rather than employing actin-based contraction, movement in plant organs relies on water flux between cells or tissues, within cellular cytoplasm or cell wall. Understanding the mechanics requires quantitative experimentation and mechanical modeling at multiple scales. This Preview introduces an intriguing paper on the explosive seed dispersal by Hofhuis et al.
Influence of electric fields and conductivity on pollen tube growth assessed via Electrical Lab-on-Chip
Agudelo CG, Packirisamy M, Geitmann A. 2016. Scientific Reports 6:19812
Elongating pollen tubes respond to the presence of electric fields. We designed a highly reproducible experimental setup based on Lab-on-Chip technology that allows researchers to assess the effect of electric field strengths and AC frequencies on single cells. Medium conductivity was found to be an important parameter determining the response of cells to the electric field.
Relating the mechanics of the primary plant cell wall to morphogenesis
Bidhendi AJ, Geitmann A. 2016. Journal of Experimental Botany 67: 449-461
Regulation of the mechanical properties of the cell wall is a key parameter used by plants to control the growth behavior of individual cells and tissues. This review covers the major cell wall polysaccharides and their implication for plant cell wall mechanics.
Navigating the plant cell: Intracellular transport logistics in the green kingdom.
Geitmann A, Nebenführ A. 2015. Molecular Biology of the Cell, 26 (19): 3373-3378
All eukaryotic cells have to shuttle material between different compartments or between different subcellular regions. The logistics of actin and microtubule-mediated intracellular transport in plant cells is discussed.
Tip growth in walled cells: Cellular expansion and invasion mechanisms
Sanati Nezhad A, Geitmann A. 2015. In: Cuerrier C, Pelling A (eds) Cells, Forces and the Microenvironment, CRC Press pp. 335-355
Plant cell morphogenesis is a process governed by a set of mechanical principles which determine how and into what shape the cell grows or how it deals with mechanical obstacles. In this review the individual concepts and vocabulary of plant cell growth in general and invasive growth in particular are explained.