Two Is Company, but Four Is a Party — Challenges of Tetraploidization for Cell Wall Dynamics and Efficient Tip-Growth in Pollen
Plant reproduction requires pollen grains to generate long tubes to fertilise the egg cells. Steady pollen tube growth and controlled rupture are crucial events that require tight coordination of tip growth and cell wall stability at the cellular level.
Genome doubling, which leads to polyploidy, generally increases cell size, including of pollen grains, and there is evidence that this can affect tip-growth control in pollen tubes, but the presence of fertile polyploids, shows these issues can be overcome by evolution.
A recent Plants review by postdoctoral researcher Dr. Jens Westermann from the Bomblies group (IMPB) discusses how genome doubling may affect tip-focused growth of pollen tubes and by what mechanisms evolution might re-tune the underlying molecular growth machinery to function in a polyploid context.
Link to the paper in external pagePlants