Extracellular matrix molecules, such as laminins, are known to
influence and guide cell migration both during embryonic development
and in tumor genesis. Laminins also guide growing nerve cell processes
during neural network formation. This impact on cell migration and
process growth is mediated through cell surface laminin receptors, such
as
integrins and dystroglycan.
To characterize laminin's impact on cell motility, we analized
long-term
videomicroscopic recordings of glial cells seeded on surfaces covered
with laminin-1. Laminin-1, one of the most extensively studied
member
of the large laminin family, was chosen as it is abundant in vertebrate
embryos and often localized to sites of cell migration and process
growth.
In harmony with the in vivo localization and putative function of
laminin-1, experiments with cultured cells show that laminin-1 supports
cell migration. It increases both cell velocity and the frequency of
direction changes (turning freqency). Changes in the direcionality of
cell migration is associated with a development of a new leading
edge and a simultaneous
remodelling of the former leading edge. Our studies reveal that this
process growth and
withdrawal dynamism is stimulated by laminin-1. Some, but not all of
laminin-1-induced motility changes are relayed through dystroglycan
receptors. Specific blocking of these receptors result in a significant
reduction of cell motility, but leaves the increased turning activity
unchanged.
Publications : Mehes et al., 2002,
Mehes et al., 2005