Asymmetric segregation of damaged proteins at cell division generates a cell that retains damage and a clean cell that supports population survival. In cells that divide asymmetrically, such as Saccharomyces cerevisiae, segregation of damaged proteins is achieved by retention and active transport. We have previously shown that in the symmetrically dividingSchizosaccharomyces pombe there is a transition between symmetric and asymmetric segregation of damaged proteins. Yet how this transition and generation of damage-free cells are achieved remained unknown.
Here, by combining in vivo imaging of Hsp104-associated aggregates, a form of damage, with mathematical modeling, we find that fusion of protein aggregates facilitates asymmetric segregation. Our model predicts that, after stress, the increased number of aggregates fuse into a single large unit, which is inherited asymmetrically by one daughter cell, whereas the other one is born clean. We experimentally confirmed that fusion increases segregation asymmetry, for a range of stresses, and identified Hsp16 as a fusion factor. Our work shows that fusion of protein aggregates promotes the formation of damage-free cells. Fusion of cellular factors may represent a general mechanism for their asymmetric segregation at division.
Research news | 2018-03-22
As ocean temperatures rise globally, all eyes are on the Arctic’s unexploited region. But several issues must be considered before diving into unchartered fishing territory
Research news | 2018-03-20
A final reply to Montoya et. al's criticism of the planetary boundaries framework
General news | 2018-03-19
In 2017, we surpassed one thousand published articles in peer-reviewed journals and we hosted the fourth international conference on resilience and sustainability science. Another year to be proud of, we think
Research news | 2018-03-14
Amid an increase in megacities, changes in ecosystems far away can affect local access to freshwater
Research news | 2018-03-12
Ten essentials for guiding action-oriented research on energy transformation and climate change
Research news | 2018-03-09
To celebrate International Women’s Day, we have been highlighting some of our women researchers at the centre. In our final profile this week, we showcase associate professor Beatrice Crona, whose work spans from small-scale fisheries governance to global drivers of change.