Tissue architecture and function are orchestrated by an intricate
repertoire of cellular adhesion and signalling receptors, and by the
surrounding extracellular matrix (ECM). The essential role of
cell–tissue interactions in guiding organogenesis was identified in
experimental embryology studies over a century ago, and in 1954
Grobstein laid down the fundamental concept of ECM being the ultimate
integrator of cellular systems. Long before the main cell adhesion
receptors were identified, Abercrombie and colleagues proposed in 1971
that cell attachment to the ECM substratum was mediated through
electron-dense plaques containing longitudinal cytoplasmic filaments
that localise to areas of the ventral cell membrane that lie close to
the substratum. In 1982, Bissell and co-workers proposed “the minimum
required unit for expression of tissue specific functions”, a model
depicting a structure in which the nucleus links to the ECM via
cytoskeletal filament bundles that connect to a hypothetical
transmembrane ECM adhesion receptor.