In:
eLife, eLife Sciences Publications, Ltd, Vol. 3 ( 2014-04-01)
Abstract:
It is often said that attack is the best form of defense; and the immune systems of plants and animals will often target the cell membranes of microbes and other pathogens in order to defend themselves. Disrupting the cell membrane causes essential contents to leak from the cell, and eventually, the cell will burst and die. Most plants and animals produce small proteins called defensins that kill microbes by attacking their cell membranes. These defensins are thought to either destabilize the cell membrane by coating its outer surface or to insert themselves into the membrane to form open pores that allow vital biomolecules to leak out of the cell. However, the exact mechanism by which defensins attack microbial membranes is not understood. In this study, Poon, Baxter, Lay et al. show that a defensin called NaD1—which was isolated from the ornamental tobacco Nicotiana alata—binds to a molecule from the cell membrane called phosphatidylinositol 4,5-bisphosphate, or PIP2 for short. By working out the three-dimensional structure of this complex, Poon, Baxter, Lay et al. show that it contains 14 PIP2 molecules and 14 NaD1 molecules in an arch-shaped structure and suggest that sequestering large numbers of PIP2 molecules in this way destabilizes the cell membrane of the microbe. These findings raise a number of questions: are there other small proteins that can destabilize cell membranes in a similar manner to defensins? Do the immune systems of other organisms also recognize molecules from microbial cell membranes to trigger this kind of counterattack? Furthermore, since defensins can also kill tumor cells, a better understanding of how they work might also lead to new treatments for cancer and other diseases in humans.
Type of Medium:
Online Resource
ISSN:
2050-084X
DOI:
10.7554/eLife.01808.001
DOI:
10.7554/eLife.01808.002
DOI:
10.7554/eLife.01808.003
DOI:
10.7554/eLife.01808.004
DOI:
10.7554/eLife.01808.005
DOI:
10.7554/eLife.01808.006
DOI:
10.7554/eLife.01808.007
DOI:
10.7554/eLife.01808.008
DOI:
10.7554/eLife.01808.009
DOI:
10.7554/eLife.01808.010
DOI:
10.7554/eLife.01808.011
DOI:
10.7554/eLife.01808.012
DOI:
10.7554/eLife.01808.013
DOI:
10.7554/eLife.01808.014
DOI:
10.7554/eLife.01808.015
DOI:
10.7554/eLife.01808.016
DOI:
10.7554/eLife.01808.017
DOI:
10.7554/eLife.01808.018
DOI:
10.7554/eLife.01808.019
DOI:
10.7554/eLife.01808.020
DOI:
10.7554/eLife.01808.021
DOI:
10.7554/eLife.01808.022
DOI:
10.7554/eLife.01808.023
DOI:
10.7554/eLife.01808.024
DOI:
10.7554/eLife.01808.025
DOI:
10.7554/eLife.01808.026
DOI:
10.7554/eLife.01808.027
DOI:
10.7554/eLife.01808.028
DOI:
10.7554/eLife.01808.029
DOI:
10.7554/eLife.01808.030
DOI:
10.7554/eLife.01808.031
DOI:
10.7554/eLife.01808.032
DOI:
10.7554/eLife.01808.033
DOI:
10.7554/eLife.01808.034
Language:
English
Publisher:
eLife Sciences Publications, Ltd
Publication Date:
2014
detail.hit.zdb_id:
2687154-3
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