Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Sci. STKE, 30 April 2002
Vol. 2002, Issue 130, p. tw162
[DOI: 10.1126/stke.2002.130.tw162]


Embryogenesis Dynamic Membrane Growth

Embryogenesis requires an increase in total cellular membrane and the generation of distinct membrane domains. In the Drosophila embryo, this membrane growth and refinement process is called cellularization and results in a polarized epithelium. Lecuit et al. show that a 135-kD membrane-associated protein called Slam (slow-as-molasses) is required for basal-lateral membrane growth. The slam mutant embryos were disrupted at gastrulation because of aberrant furrow canal formation and membrane invagination. As a result, no basal-lateral region distinct from the apical membrane was formed, nor were junctions between adjacent plasma membranes. Ectopically expressed Slam localized to the plasma membrane of the furrow canal and to the adjacent basal-lateral membrane during the first, slow phase of embryonic cellularization. Slam expression decreased in the later, fast phase of cellularization just before gastrulation. The transport of two membrane proteins, neurotactin and Toll, was also inhibited in slam mutants. Slam colocalized with Discs-lost and Armadillo, two proteins required for maintaining cell junctions. Myosin localization to these junctions was compromised in slam mutants. The authors propose that Slam could induce the formation of protein complexes that connect the actin-myosin cytoskelton to distinct regions of membrane growth and further stabilize or enhance functional insertion of membranes basal-laterally during the process of cell polarization.

T. Lecuit, R. Samanta, E. Wieschaus, slam encodes a developmental regulator of polarized membrane growth during cleavage of the Drosophila embyro. Dev. Cell 2, 425-436 (2002). [Online Journal]

Citation: Dynamic Membrane Growth. Sci. STKE 2002, tw162 (2002).

To Advertise     Find Products

Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882