Breadcrumb

Kumaran S. Ramamurthi, Ph.D.

Kumaran S. Ramamurthi, Ph.D.

  • Center for Cancer Research
  • National Cancer Institute

RESEARCH SUMMARY

Dr. Ramamurthi’s laboratory studies fundamental mechanisms that cells use to differentiate and divide in an effort to understand how these processes may go awry during disease. His lab focuses on how proteins localize to particular subcellular locations and how they subsequently assemble to form large structures during development and cell division. Recently, he discovered that the shape of cellular membranes, either convex or concave, may recruit certain membrane shape-sensing proteins to their correct destination, a novel mechanism for subcellular protein localization.

Areas of Expertise

1) microbiology, 2) protein trafficking, 3) cellular differentiation, 4) cell division,
5) cytoskeleton, 6) fluorescence microscopy

Publications

Selected Key Publications

Bacterial developmental checkpoint that directly monitors cell surface morphogenesis

Delerue, T., Anantharaman, A., Gilmore, M.C., Popham, D.L., Cava, F., Aravind, L., and Ramamurthi, K.S.
Developmental Cell. 57: 344-360, 2022.
Full-Text Article
[ Journal Article ]

Reformulation of an extant ATPase active site to mimic ancestral GTPase activity reveals a nucleotide base requirement for function

Updegrove TB, Harke J, Anantharaman V, Yang J, Gopalan N, Wu D, Piszczek G, Stevenson DM, Amador-Noguez D, Wang JD, Aravind L, Ramamurthi KS.
Elife. 10: e65845, 2021. [ Journal Article ]

A 2-dimensional ratchet model describes assembly initiation of a specialized bacterial cell surface

Peluso EA, Updegrove TB, Chen J, Shroff H, Ramamurthi KS
Proc Natl Acad Sci U S A. 116: 21789-21799, 2019. [ Journal Article ]

An essential Staphylococcus aureus cell division protein directly regulates FtsZ dynamics

Eswara PJ, Brzozowski RS, Viola MG, Graham G, Spanoudis C, Trebino C, Jha J, Aubee JI, Thompson KM, Camberg JL, Ramamurthi KS
eLife. e38856, 2018. [ Journal Article ]

Dash-and-Recruit Mechanism Drives Membrane Curvature Recognition by the Small Bacterial Protein SpoVM

Kim EY, Tyndall ER, Huang KC, Tian F, Ramamurthi KS.
Cell Syst.. 5(5): 518-526, 2017.

Job Vacancies

Graduate students who are interested in a postdoctoral fellowship are encouraged to send their CV directly to Kumaran Ramamurthi (ramamurthiks@mail.nih.gov).

Team

Postdoctoral Fellow (Visiting)
Sylvia Chareyre, Ph.D.
Postdoctoral Fellow (Visiting)
Domenico D’Atri , Ph.D.
Postdoctoral Fellow (Visiting)
Felix Ramos-Leon, Ph.D.
Postdoctoral Fellow (CRTA)
Christina Savage, Ph.D.
Staff Scientist
Taylor Updegrove, Ph.D.
postdoctoral fellow
Federico Machinandiarena, Ph.D.

Covers

Cover page of Developmental Cell 2022 issue 57

Bacterial developmental checkpoint that directly monitors cell surface morphogenesis

Published Date

The bacterium Bacillus subtilis undergoing spore formation is depicted using toys. Membranes are depicted using marbles. The spore is encased in two concentric shells: an outer proteinaceous “coat” (green and red blocks) and a peptidoglycan “cortex” (orange dodecahedron). To learn more about how coat assembly is linked to cortex formation, see Delerue et al. (pp. 344–360). 

Citation

Delerue, T., Anantharaman, A., Gilmore, M.C., Popham, D.L., Cava, F., Aravind, L., and Ramamurthi, K.S. Bacterial developmental checkpoint that directly monitors cell surface morphogenesis Developmental Cell 2022; 57:344-360 <https://www.sciencedirect.com/science/article/pii/S1534580721010418?via%3Dihub>

Cover of mBio, November 22, 2011

Cellular architecture mediates DivIVA ultrastructure and regulates min activity in Bacillus subtilis

Published Date

The Min system in rod-shaped bacteria restricts improper assembly of the division septum. In Escherichia coli, the Min system localizes to the cell poles, but in Bacillus subtilis, it is recruited to nascent cell division sites at mid-cell to prevent aberrant septation events immediately adjacent to a constricting septum. How does the cell spatially and temporally restrict the inhibitory activity of the Min system so that it does not interfere with normal cell division? This image reveals (using a super-resolution fluorescence microscopy technique called SIM) that the cell division protein DivIVA (green), which preferentially localizes to negatively curved membranes (red) and is responsible for recruitment of the Min system, localizes as double rings on either side of actively constricting septa and remains associated with mature septa after completion of cell division.

In the related article, the authors propose that DivIVA interprets membrane invagination as evidence of cell division and localizes to mid-cell only after the onset of membrane constriction. Additionally, the formation of two ring-shaped platforms on either side of the septum reveals a mechanism by which the inhibitory activity of the Min system is held away from a newly forming septum, while simultaneously inhibiting aberrant septation at sites immediately adjacent to mid-cell.

Citation

Cellular architecture mediates DivIVA ultrastructure and regulates min activity in Bacillus subtilis
Prahathees Eswaramoorthya, Marcella L. Erbb, James A. Gregoryb, Jared Silvermanc, Kit Poglianob, Joe Poglianob,  and Kumaran S. Ramamurthia. mBio 2(6):e00257–11, 2011.

aLaboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
bDivision of Biological Sciences, University of California at San Diego, La Jolla, California, USA
cCubist Pharmaceuticals, Lexington, Massachusetts, USA