Stuti K DESAI
Alumni, Mechanobiology Institute, National University of Singapore
Latest publication on tissue hydraulics in reproduction is out!
Joe and Tsuyoshi Hirashima (incoming PI) reviewed recent advances in our understanding on how fluid dynamics shape mammalian oogenesis and spermatogenesis.
Talk at EMBO/EMBL Symposium on Mechanobiology in development and disease
Joe shares the latest finding on theca cell mechanosensing and their function in controlling follicle growth at the 2022 EMBO/EMBL symposium on mechanobiology in development and disease.
Modhura Ganguly
PhD Student, Class of January 2022, Toyama Group
Martin Kiwanuka
PhD Student, Class of January 2022, Young Group
A Nervous Contraction
A collaborative study from the Saunders Lab and the Martin-Blanco Lab at the Molecular Biology Institute Barcelona, Spain, demonstrates how the contraction of a Drosophila's ventral nerve cord during development is oscillatory and driven by the combined contractile efforts of individual cells. Learn more
MBI welcomes NUS High School for a Learning Journey into Mechanobiology
MBI opened its doors to the students of NUS High School of Mathematics and Science for a half-day visit around the institute.
Stuti K Desai
Alumni 2020
Principal Investigator
Research Interests
Molecular Mechanisms of Mechanobiology
A fundamental trait shared amongst many mammalian pathogens is their ability to exist in different forms in order to survive and replicate in often fluctuating host and non-host environments. Two important gut pathogens, Salmonella Typhimurium and Salmonella Typhi, which cause gastroenteritis and typhoid fever, respectively, survive inside host cells by activation of a specific class of virulence genes. Salmonellae also develop to form hardy multi-cellular communities, called biofilms, on host tissues for successful survival and persistence in asymptomatic carriers. An active area of research focuses on understanding how the genetic program is regulated in coordination with environmental changes to evoke lifestyle changes. We recently discovered that SsrB, the transcriptional regulator of virulence genes, has the additional function of inducing biofilm formation by activating expression of the central biofilm regulator, CsgD. Generally, specific environmental changes activate a membrane-bound kinase, which in turn transfers the phosphoryl group to a transcriptional regulator in order to regulate virulence gene transcription. But, we discovered that even without phosphorylation, SsrB retains the ability to bind DNA and relieve the H-NS-mediated repressive effect on csgD transcription. SsrB is thus a molecular switch which drives the twin lifestyles of Salmonella Typhimurium; as SsrB~P, when phosphorylated by an actived SsrA kinase, it activates around 30 virulence genes required for survival within the host; and as SsrB, in the case when SsrA is inactive or absent, it counters transcriptional silencing at csgD to form biofilms.
For this study, we utilized the highly collaborative atmosphere at MBI and studied the behavior of the activator, SsrB, and the repressor, H-NS, at the csgD regulatory site using single molecule approaches with Prof. Yan Jie’s group. Going forward, I want to build on the diverse expertise at MBI and other groups in the region to extend these findings and study the specific mechanisms of lifestyle changes in more aggressive strains of Salmonella and validate the underlying signaling pathways in heterologous hosts as model systems.
Research Areas
Bacterial gene regulation, Biofilms, Host-pathogen interactions and Virulence strategies of Salmonellae
Biography
Dr. Stuti Desai joined the group of Prof. Linda Kenney at the Mechanobiology Institute, in 2012, after obtaining her doctorate from the Indian Institute of Science, Bangalore, India, under the guidance of Prof. Subramony Mahadevan. Her graduate studies involved deciphering the regulatory mechanisms that maintain the beta-glucoside utilization systems in a silent state in commensal as well as pathogenic gut bacteria. Prior to that, she studied Biochemistry for her Masters degree at the Maharaja Sayajirao University of Baroda, Baroda, India.
