09 February 2010

Young cells send dirty laundry to moms

Scientists at the University of Gothenburg (Sweden), working under the guidance of Professor Thomas Nyström, have deciphered the mechanism that allows battered maternal cells to bud off from themselves daughter cells that are not burdened with the load of damaged proteins that inevitably accumulate in each cell during its vital activity.

It turns out that daughter cells use conveyor-like structures that ensure the movement of all morally and physically obsolete protein molecules into the mother cell. As a result, after complete separation from the mother cell, the daughter cell is completely free of age-associated damage.

Previously, it was believed that these structures formed by fibers from the actin protein provide one-way movement of proteins and cellular organelles from the mother cell to the daughter cell. The authors have shown that reverse movement is also possible, ensuring the transportation of damaged proteins to the mother cell, which in this case serves as a kind of "dumpster".

(In the picture and in the video – bright green protein aggregates are transported from a young cell to a larger mother cell).

In their work, the authors demonstrated that this transportation is carried out due to the mechanical forces of reduction of actin fibers. They also found that the correct formation of these fibers is impossible without the normal functioning of the SIR2 gene and its protein product involved in the aging processes of the body. Earlier studies on yeast, worms, fruit flies and fish have shown that an increase in the activity of the SIR2 gene can significantly increase the lifespan of an organism, and its damage accelerates the aging process.

Professor Nistrem believes that knowledge of the mechanism used by daughter cells to transport damaged proteins to the mother cells can form the basis for the treatment of age-related diseases caused by the accumulation of damaged proteins with toxic properties. At the same time, he emphasizes that today it is still completely unclear how this information can be applied to mammals. He also notes that at the next stage of the work, scientists should find out whether mammalian cells use a similar mechanism in the formation of germ and stem cells.

Article by Beidong Liu et al. "The Polarisome Is Required for Segregation and Retrograde Transport of Protein Aggregates" is published in Cell magazine on January 22.

Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of the University of Gothenburg: Cells send dirty laundry home to mom.


Found a typo? Select it and press ctrl + enter Print version