The ability to transduce a signal across a membrane is a basic biological phenomenon that remains only poorly understood. Recently, a new mechanism of transduction across a membrane has been described. In this model proteases embedded within the membrane are triggered to catalyze the proteolytic release of membrane-anchored transcription factors. These novel proteases are polytopic membrane proteins with catalytic sites embedded in the lipid bilayer. To gain a deeper understanding into how information is transduced by these membrane-embedded proteases we are studying a signal transduction pathway that results in the proteolytic activation of a transcription factor involved in spore formation in the bacterium Bacillus subtilis. The ease with which genetic and biochemical analysis can be carried out in this organism makes this an ideal system to study this important class of proteases. The developmentally regulated transcription factor (sigmaK) is proteolytically released from the membrane by a membrane-embedded metalloprotease known as SpolVFB (referred to as B). B is activated by a signaling protease (IVB) located on the other side of the membrane. The specific hypothesis underlying the proposed research is that cell-cell signaling during sporulation is achieved by the action of IVB on one side of the membrane, which triggers the activity of the membrane-embedded metalloprotease B on the opposite side. We further hypothesize that additional regulatory proteins modulate this two-step proteolytic cleavage pathway, which results in transcription factor activation. Specifically, we propose to: 1. Determine how the IVB signaling molecule triggers B protease activity; 2. Characterize three regulators that modulate the timing of sigmaK activation; 3. Reconstitute and characterize B-mediated pro-sigmaK processing in vitro.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM073831-02
Application #
7125522
Study Section
Prokaryotic Cell and Molecular Biology Study Section (PCMB)
Program Officer
Chin, Jean
Project Start
2005-09-23
Project End
2010-08-31
Budget Start
2006-09-01
Budget End
2007-08-31
Support Year
2
Fiscal Year
2006
Total Cost
$372,413
Indirect Cost
Name
Harvard University
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
047006379
City
Boston
State
MA
Country
United States
Zip Code
02115
Fenton, Andrew K; Manuse, Sylvie; Flores-Kim, Josué et al. (2018) Phosphorylation-dependent activation of the cell wall synthase PBP2a in Streptococcus pneumoniae by MacP. Proc Natl Acad Sci U S A 115:2812-2817
Fenton, Andrew K; El Mortaji, Lamya; Lau, Derek T C et al. (2017) Erratum: CozE is a member of the MreCD complex that directs cell elongation in Streptococcus pneumoniae. Nat Microbiol 2:17011
Ramírez-Guadiana, Fernando H; Meeske, Alexander J; Wang, Xindan et al. (2017) The Bacillus subtilis germinant receptor GerA triggers premature germination in response to morphological defects during sporulation. Mol Microbiol 105:689-704
Koo, Byoung-Mo; Kritikos, George; Farelli, Jeremiah D et al. (2017) Construction and Analysis of Two Genome-Scale Deletion Libraries for Bacillus subtilis. Cell Syst 4:291-305.e7
Wang, Xindan; Brandão, Hugo B; Le, Tung B K et al. (2017) Bacillus subtilis SMC complexes juxtapose chromosome arms as they travel from origin to terminus. Science 355:524-527
Meeske, Alexander J; Riley, Eammon P; Robins, William P et al. (2016) SEDS proteins are a widespread family of bacterial cell wall polymerases. Nature 537:634-638
Meeske, Alexander J; Rodrigues, Christopher D A; Brady, Jacqueline et al. (2016) High-Throughput Genetic Screens Identify a Large and Diverse Collection of New Sporulation Genes in Bacillus subtilis. PLoS Biol 14:e1002341
Rodrigues, Christopher D A; Ramírez-Guadiana, Fernando H; Meeske, Alexander J et al. (2016) GerM is required to assemble the basal platform of the SpoIIIA-SpoIIQ transenvelope complex during sporulation in Bacillus subtilis. Mol Microbiol 102:260-273
Widderich, Nils; Rodrigues, Christopher D A; Commichau, Fabian M et al. (2016) Salt-sensitivity of ?(H) and Spo0A prevents sporulation of Bacillus subtilis at high osmolarity avoiding death during cellular differentiation. Mol Microbiol 100:108-24
Wang, Xindan; Montero Llopis, Paula (2016) Visualizing Bacillus subtilis During Vegetative Growth and Spore Formation. Methods Mol Biol 1431:275-87

Showing the most recent 10 out of 33 publications