Biology Department Faculty

Our research employs broad interdisciplinary approaches in cell and molecular biology and genetics, with special expertise in quantitative live-cell imaging. We also collaborate closely with engineers and mathematicians to build predictive models of these regulatory mechanisms. The research in our lab is funded by the National Science Foundation (Molecular and Cellular Biosciences) and the National Institutes of Health/NIGMS. Following are the current projects in the lab.

Cells are highly efficient machines that operate with great precision to promote proliferation and function. The Das lab is interested in understanding the fundamentals of cell shape and cell division. These are complex processes that operate in an error-free manner thanks to intricate regulatory patterns that organize multi-step processes in time and space. Studies from our lab as well as others have shown that these regulatory patterns involve self-organization of higher-order molecular networks. We explore these molecular networks using mainly the single-celled eukaryotic model system Schizosaccharomyces pombe, or fission yeast. Fission yeast cells have a well-defined shape and growth pattern, and divide by actomyosin-ring-dependent cytokinesis, making it an excellent model system for our investigations.

Denotes the following: §Graduate students, #Undergraduate students, †High School students

Preprint:

1. Onwubiko UN§, Koory E#, Pokharel S#, Roberts H#, Mitoubsi A, Das M. 2022. Cdc42 prevents precocious Rho1 activation during cytokinesis in a Pak1-dependent manner. bioRxiv doi:10.1101/2022.06.14.496145

Peer-reviewed:

1. Campbell BF§, Hercyk BS§, Williams AR #, San Miguel ES #, Young HG #, Das ME. 2022. Cdc42 GTPase activating proteins Rga4 and Rga6 coordinate septum synthesis and membrane trafficking at the division plane during cytokinesis. Traffic, in Press, doi:10.1111/tra.12864.

2. Rich-Robinson J§, Russell A#, Mancini E†, Das ME. 2021. Cdc42 reactivation at growth sites is regulated by cell-cycle-dependent loss of its GAP Rga4. Journal of Cell Science, in Press, doi: 10.1242/jcs.259291

Work Featured in: Research highlights, Journal of Cell Science

3. Rodriguez Pino M, Nuñez I, Chen C, Das ME, Wiley DJ, D’Urso G, Buchwald P, Vavylonis D, Verde F. 2021. Cdc42 GTPase Activating Proteins (GAPs) Regulate Generational Inheritance of Cell Polarity and Cell Shape in Fission Yeast. Molecular Biology of the Cell, Jul 21, doi: 10.1091/mbc.E20-10-0666

4. Onwubiko UN§, Rich-Robinson J§, Mustaf RA†, Das ME. 2019. Cdc42 promotes Bgs1 recruitment for septum synthesis and glucanase localization for cell separation during cytokinesis in fission yeast. Small GTPases 2020, Mar 22:1-8.

5. Hercyk B§, Rich J§, Mitoubsi A, Harrell M, Das M. 2019. A novel interplay between GEFs orchestrates Cdc42 activation in cell polarity and cytokinesis. Journal of Cell Science 2019, 132:jcs236018-jcs236018.

Work Featured in: preLights, Company of Biologists.

6. Hercyk B§ and Das M. 2019. F-BAR Cdc15 Promotes Gef1-mediated Cdc42 Activation During Cytokinesis and Cell Polarization in S. pombe. Genetics, 2019, 213 (4): 1341-1356.

7. Hercyk B§ and Das M. 2019. Rho Family GTPases in Fission Yeast Cytokinesis. Communicative and Integrative Biology, 12(1):171–180. Published 2019 Oct 21.

8. Hercyk B§, Onwubiko UN§, Das M. 2019. Coordinating Septum Formation and the Actomyosin Ring during Cytokinesis in Schizosaccharomyces pombe. Molecular Microbiology, 112(6):1645–1657.

9. Onwubiko UN§, Mlynarczyk PJ§, Wei B, Habiyaremye J#, Clack A#, Abel SM, Das ME. A Cdc42 GEF, Gef1, through endocytosis organizes F-BAR Cdc15 along the actomyosin ring and promotes concentric furrowing. Journal of Cell Science 2019 132: jcs223776 doi: 10.1242/jcs.223776 Published 28 February 2019.

Work Featured in: Editor’s highlight, Journal of Cell Science

10. Wei B, Hercyk BS§, Habiyaremye J#, Das M. 2017. Spatiotemporal analysis of cytokinetic events in fission yeast. JoVE, 120.

11. Nuñez I, Rodriguez Pino M, Wiley DJ, Das M, Chen C, Goshima T, Kume K, Hirata D, Toda T and Verde F. 2016. Spatial control of translation repression and polarized growth by conserved NDR kinase Orb6 and RNA-binding protein Sts5. eLife, pii:e14216.

12. Wei B, Hercyk BS§, Mattson N, Mohammadi A#, Rich J#, DeBruyne E#, Clark MM#, Das M. 2016. Unique Spatiotemporal Activation Pattern of Cdc42 by Gef1 and Scd1 Promotes Different Events during Cytokinesis. Molecular Biology of the Cell. 27(8):1235-45.

Work Featured in: Molecular Biology of the Cell, American Society for Cell Biology newsletter.

13. Das M, Nuñez I, Rodriguez M, Wiley D J, Rodriguez J, Sarkeshik A, Yates III. J R, Buchwald P, and Verde F. 2015. “Phosphorylation-dependent inhibition of Cdc42 GEF Gef1 by 14-3-3 protein Rad24 spatially regulates Cdc42 GTPase activity and oscillatory dynamics during cell morphogenesis.” Molecular Biology of the Cell, 26(19):3520-34.

14. Das M, Verde F. 2013. “Role of Cdc42 dynamics in the control of fission yeast cell polarization.” Biochem Soc Trans. 41(6):1745-9.

15. Das M*, Drake T*, Buchwald P, Vavylonis D and Verde F. 2012. “Oscillatory dynamics of Cdc42 GTPase in the spatial control of polarized cell growth.” Science, 2012, 337, 6091, 239-243. * Co-authors

Work Featured in: Editors’ Choice Cell Biology “Pole to Pole” Sci. Signal.
Faculty of 1000 Biology

16. Das M, Chiron S and Verde F. 2010. “Microtubule-dependent spatial organization of mitochondria in fission yeast.” Methods in Cell Biology, 97, 203-21

17. Das M, Wiley D J, Chen X, Shah K and Verde F. 2009. “Conserved NDR kinase Orb6 controls polarized cell growth by spatial regulation of the small GTPase Cdc42.” Current Biology, 19, 1314-19.

Work Featured in: Faculty of 1000 Biology.

18. Iyer R S, Das M and Bhat P J. 2008. “Pseudohyphal differentiation defect due to mutations in GPCR and ammonium signaling is suppressed by low glucose concentration: A possible integrated role for Carbon and Nitrogen limitation.” Current Genetics, 54, 71-81

19. Das M*, Wiley D J*, Medina S, Vincent H, Larrea M, Oriolo A and Verde F. 2007. “Regulation of cell diameter, For3p localization and cell symmetry by fission yeast Rho-GAP Rga4p.” Molecular Biology of the Cell, 18, 2090-101. * Co-authors

Work Featured in: InCytes in the June Issue of Molecular Biology of the Cell and American Society for Cell Biology newsletter.

20. Das M and Bhat P J. 2005. “Disruption of MRG19 results in altered nitrogen metabolic status and defect in pseudohyphal development: Evidence for a link between metabolic status and developmental pathway.” Microbiology, 151, 91-8

Work Featured in: Faculty of 1000 Biology.

21. Khanday F A, ‡Saha M and Bhat P J. 2002. “Molecular Characterization of MRG19 of Saccharomyces cerevisiae. Implication in the Regulation of Galactose and Nonfermentable Carbon Source Utilization.” European Journal of Biochemistry, 269, 5840-50 (‡Maiden name)