Vaidurya Sahi Michael Riemann

Vaidurya Sahi

  • Botanisches Institut, Fritz-Haber-Weg 4, 76131 Karlsruhe

Profil Vaidurya Sahi


1. BSc Agriculture and Technology. Allahabad Agricultural Institute (Deemed University), India. Grade: 9.18/10 Year 2001- 05

2. MSc Plant Breeding and Genetics. Tamil Nadu Agricultural University, India. Grade: 8.23/10 Year 2005- 07

3. PhD Molecular Biology. Ehime University, Japan. Year 2008- 12


Previous works:

Coming from a traditionally agricultural family of India, I studied agriculture during my bachelors' degree and graduated in  my Masters with a MSc degree in Plant Breeding and Genetics. With a Monbukagakusho fellowship (MEXT) from Japan, I did my PhD in Molecular Biology under Dr Shunnosuke Abe at Ehime University, Japan. During my PhD I studied the expression pattern of makorin (MKRN) gene in young stages of  plant and animal development. Our insilico analyses suggested that the MKRNs present in extant invertebrates, vertebrates and plants have arisen from a single ancient progenitor MKRN locus. Alignment of plant and animal MKRN homologs showed the highly conserved nature of the signature zinc-finger motifs, underscoring their putative functional importance and strongly supporting a homologous relationship between the plant and animal genes. To make an anology of the expression pattern of MKRN gene in plants and animals, we performed the first meticulous analysis of spatio-temporal expression pattern of MKRN in various life events during embryonic as well as post-embryonic organogenesis in pea and rice plants. Presence of MKRN transcripts not only during embryogenesis and different tissues of different organs during organogenesis but also its differential pattern of expression during functionally distant cell metabolic activities suggest basic role of MKRN during development. After the completion of my PhD and my postdoctoral stint at S Korea, I joined the laboratory of Dr Katerina Schwarzerova at Charles University in Prague. I worked on a project to understand the functional role of actin nucleator, ARP2/3 complex, in plants. This actin nucleating complex ARP2/3, is comprised of seven subunits, and is highly conserved in eukaryotes. Till recently  it was known that unlike non-plant cells, where the loss of the ARP2/3 complex is often detrimental, plants lacking one of the ARP2/3 complex subunit show rather mild phenotypes like distorted shapes of trichomes or changes in pavement cell morphology in Arabidopsis. We after carefully analyzing the plants lacking ARP2, ARPC4 and ARPC5 subunits, found new phenotypes. Besides specific changes in the morphology of epidermal leaf cells, we have detected that the number of cell layers in leaves and stems of mutants was lower. Moreover, the organization of cells in these tissues was disturbed and changes in the cell wall composition have been detected as well. These changes are accompanied by defects in the distribution of auxin transporters and altered distribution of auxin within tissues. The defects in cell shape is presumably based on either improper dynamics of auxin carriers themselves or more general effects on the trafficking of numerous other proteins. We hypothesize that ARP2/3 complex-driven actin dynamics is essential for cell morphogenesis and tissue organization through the control of transporters needed for auxin transport and the cell wall building. This has opened prospects for a new crosstalk between cytoskeleton and  auxin with an emphasis on cell wall.


Present Work: 

The feeling of joining Nick lab  is  similar  to what Alexander  von Humboldt felt on starting his voyage to South America: "My mood was good just as it should be when beginning a great work". 

A brief description of the work i am involved in:

1. What drives the "Bildungstrieb" in a cell or life in general has been a question being asked for  centuries. Modern techniques and a better understanding of  physics of the living world has brought us closer to the goal of understanding the Bildungstrieb. 

It is well known now, that the cytoskeleton (microtubules and actin filaments) orchestrates a synchronized  mechanointegration which paves way for the cell division. And for this synchronized mechanointegration, the microtubules and actin filaments need to  couple together, which is brought about by  Kinesins of the class 14 family (KCH - Kinesins). A better understanding of these kinesins will help to unravel the underlying architectural role played by the cytoskeleton in a plant's life, which in turn can  help to develop plant types with desired  shapes especially for agriculture. In collaboration with Dr Wim Walters of Hamburg University, in the present project, we intend to understand the role of OsKCH1 gene in development of the leaf. Using quantitative gene expression studies and further phenotyping of the  mutant kch1lines of rice, the project intends to find the role of this gene in leaf development  in context to geometric parameters like leaf angle, length width and spatio temporal growth.

2. The botanical garden of KIT has a collection of ayurvedic and medicinal plants. These plants are exotic to Germany and are used very commonly in  commercially available super/health foods. Genetic barcoding and phenotypic characterization of these plants  will help to identify the ingredients of the super/health foods, if need be. We intend to profile (genotypically and phenotypically) these  ayurvedic plants so as to greate a descriptive database of the plants for future  academic or investigative purposes.


Selected Publications:

1. Expression of a gene encoding a MKRN RING zinc finger protein in early germination stages of pea (Pisum sativum L.Var. Alaska) and its possible role in differentiation. Sahi V P, Arumugam T U, Morita E H, Abe S. Acta Physiologiae Plantarum, 33:1759-67, (2011)

2. A molecular insight into Darwin’s 'plant brain hypothesis' through expression pattern study of the MKRN gene in plant embryo compared with mouse embryo. Sahi V P, Wadekar H B, Ravi S N, Arumugam T U, Morita E H, Abe S. Plant Signaling and Behavior, 7: 375-381 (2012) 

3.  MKRN expression pattern during embryonic and post-embryonic organogenesis in rice (Oryza sativa L. var. Nipponbare). Wadekar H B, Sahi V P, Morita E H, Abe S. Planta, 237 (4), 1083-1095 (2012)

4. Makorin RING zinc finger protein gene expresses during leaf vascular pattern development in rice (Oryza sativum L. var. Nipponbare). Wadekar H B, Sahi V P, Morita E H, Abe S. International Research Journal of Biological Sciences , 3 (3), 45-51 (2014)