How Some Algae Tolerate Very Salty Environments

Newswise — Researchers have identified unique proteins that allow a unicellular alga called Dunaliella salina to proliferate in environments with extreme salt content. These results, which appear in the September issue of Molecular & Cellular Proteomics, might provide ways to help crop plants resist the progressive accumulation of salt in soil, which is a major limitation for agricultural productivity worldwide.

Since its discovery in 1905, D. salina has become a convenient model organism to study general mechanisms of salt adaptation in algae and plants. Previous studies have shown that in very salty environments, the alga's plasma membrane -- which is a barrier that protects it from the outside environment -- undergoes major changes that are expected to play a role in salinity tolerance.

For the first time, Adriana Katz and colleagues have obtained a comprehensive overview of membrane-associated proteins and have shown how changes in the structure and composition of the membrane may help D. salina adapt to high salt content.

The scientists identified 55 proteins, many of which have not been discovered before. Some of these proteins strengthen the membrane against rupture, activate salt elimination, and enable the cells to sense and signal changes in salt levels in the environment. These results highlight proteins and mechanisms that play a key role in salinity tolerance and could pave the way for improving salinity tolerance in other organisms.

Article: "Salt-induced Changes in the Plasma Membrane Proteome of the Halotolerant Alga Dunaliella salina as Revealed by Blue Native Gel Electrophoresis and Nano-LC-MS/MS Analysis," by Adriana Katz, Patrice Waridel, Andrej Shevchenko, and Uri Pick

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