Exploring the matrix
Cells communicate with the matrix surrounding them
Tissues contain cells and material between the cells. In connective tissues, like bone or tendon, this material – the extracellular matrix – predominates. In other tissues, it is distributed more sparingly. In all tissues, the cells and their matrix communicate, chemically and physically.
The physical link is via proteins that cross the external membrane of the cell, which are known as integrins. One end of an integrin is linked to the cell’s cytoskeleton, the other to collagen fibres in the extracellular matrix.
The matrix also contains chemical messengers, often bound to gels made up of proteoglycans, a complex mix of proteins and the sugar-derived polysaccharides made in the Golgi apparatus. These include growth factors and signal molecules, which affect many processes, including cell migration.
Some of these messengers come from the cells that make the matrix, some from other cell types – and the receiving cells, in turn, respond to the mix of signals as it changes over time.
New research has shown that the matrix is an important aspect of cancer biology. Cancer can cause the matrix to become unregulated and disorganised, which can cause the growth and spread of cancer.Lead image:
C Merrifield and M Duchen