Biology Reference
In-Depth Information
Initial Steps from Cell Migration
to Cell-cell Adhesion
Jason S. Ehrlich, W. James Nelson
and
Marc D. H. Hansen
High resolution time-lapse microscopy, quantitative image analysis and
biochemical analysis of protein complexes reveal that cell-cell contact in
MDCK epithelial cells coincides with a spatio-temporal reorganization of
plasma membrane Rac1 and lamellipodia from non-contacting to contacting
surfaces. Later stages of adhesion involve compaction of the contact and it
appears that activation of actin-myosin contraction is required for this process
and that the activity of this complex may be spatially constrained to the lateral
edges of the contact. We propose a mechanism in which force vectors
perpendicular to the contact initiate cell-cell adhesion by forcing membranes
and cadherins into contact, but that subsequently, force vectors parallel to the
contact further extend, strengthen and eventually compact the contact.
Introduction
Multicellular organisms comprise heterogeneous cell types that are organized
during development into distinct patterns to form tissues and organs
(Trinkaus, 1965). One of the most important primary processes involved in
regulating the establishment and maintenance of these patterns is cell-cell
adhesion. A central principle is that the interaction between cells within
heterogeneous cell populations is based upon the specificity and extent of
