dictyNews

Electronic Edition

Volume 48, number 11

June 3, 2022



Please submit abstracts of your papers as soon as they have been

accepted for publication by sending them to [log in to unmask]

or by using the form at

http://dictybase.org/db/cgi-bin/dictyBase/abstract_submit.



Back issues of dictyNews, the Dicty Reference database and other

useful information is available at dictyBase - http://dictybase.org.



Follow dictyBase on twitter:

http://twitter.com/dictybase





=========

Abstracts

=========





Adhesion of Dictyostelium amoebae to surfaces: a brief history 

of attachments



Lucija Mijanovic and Igor Weber



Division of Molecular Biology, Rudjer Boskovic Institute, Croatia





Frontiers in Cell and Developmental Biology, accepted



Adhesion of Dictyostelium amoebae to extracellular material relies 

on mechanisms that resemble the analogous process in animal cells. 

Notably, the cellular anchorage loci in Amoebozoa and Metazo are 

both arranged in the form of discrete spots and incorporate a similar 

repertoire of intracellular proteins assembled into multicomponent 

complexes located on the inner side of the plasma membrane. 

Surprisingly, however, Dictyostelium lacks integrins, the canonical 

transmembrane heterodimeric receptors that dominantly mediate 

adhesion of cells to the extracellular matrix in multicellular animals. 

In this review article, we summarize the current knowledge about the 

cell-substratum adhesion in Dictyostelium, present an inventory of the 

involved proteins, and draw parallels with the situation in animal cells. 

The emerging picture indicates that, while retaining the basic molecular 

architecture common to their animal relatives, the adhesion complexes 

in free-living amoeboid cells have evolved to enable less specific 

interactions with diverse materials encounteredin their natural habitat 

in the deciduous forest soil. Dissection of molecular mechanisms that 

underlay short lifetime of the cell-substratum attachments and high 

turnover rate of the adhesion complexes in Dictyostelium should provide 

insight into a similarly modified adhesion phenotype that accompanies 

the mesenchymal-amoeboid transition in tumor metastasis.





Submitted by Lucija Mijanovic [[log in to unmask]]

———————————————————————————————





Cells responding to chemoattractant on a structured substrate



Laura Rußbach, Mary Ecke, Joachim O. Rädler, Charlott Leu, and 

Günther Gerisch



Max Planck Institute of Biochemistry, Cell Dynamics Group, Germany

LMU Munich, Soft Condensed Matter Group, Germany





Biophysical Journal, accepted



Cell migration on an adhesive substrate surface comprises actin-

based protrusion at the front and retraction of the tail in combination 

with coordinated adhesion to, and detachment from, the substrate. In 

order to study the effect of cell-to-substrate adhesion on the chemotactic 

response of Dictyostelium discoideum cells, we exposed the cells to 

patterned substrate surfaces consisting of adhesive and inert areas, 

and forced them by a gradient of chemoattractant to enter the border 

between the two areas. Wild-type as well as myosin II deficient cells stop 

at the border of an adhesive area. They don’t detach with their rear part, 

while on the non-adhesive area they protrude pseudopods at their front 

toward the source of chemoattractant. Avoidance of the non-adhesive 

area may cause a cell to move in tangential direction relative to the 

attractant gradient, keeping its tail at the border of the adhesive surface.

 



Submitted by Mary Ecke [[log in to unmask]]

=======================================================

[End dictyNews, volume 48, number 11]