The microtubule (MT) cytoskeleton gives the eukaryotic cells of the body their shape, helps organise the cell’s parts, and provides a basis for movement and cell division. Yet, the basic principles regulating the position of MTs in interphase cells before cell division takes place are largely unknown.
The endoplasmic reticulum (ER), which constitutes more than half of the membranous content of a cell, has long been known to produce and transport proteins for the rest of the cell to function. However, a new paper led by Department of Physiology, Anatomy and Genetics (DPAG) Associate Professor Robin Klemm and first authored by Dr Maria S. Tikhomirova, has uncovered an unexpected role for the ER in controlling the organisation of the MT cytoskeleton in the cell. According to Prof Klemm: “This new perspective on the role of the ER in cellular organisation opens up a number of research directions and will lead to better understanding of mechanisms that cells use to position the MT cytoskeleton during migration or initiation and maintenance of axons.”
Using cutting edge computer simulation and automated microscopy, researchers have found that the dynamics of the ER network is pivotal in directing the sub-cellular distribution of MTs. In particular, they discovered that inhibition of membrane fusion in the ER leads to dramatic changes in ER network dynamics, namely strong re-positioning of both the ER membranes and the MT-cytoskeleton within cells.