More Epithelial Nudging

If you’ll recall, back in December, I provided evidence that unicellular organisms were endowed with components (beta catenins) that served as preadaptations to nudge epithelial tissue into existence when needed.

Well, feast your eyes on a paper that was published in Science just a couple of weeks ago.

A polarized epithelium organized by beta- and alpha-catenin predates cadherin and metazoan origins.
Dickinson DJ, Nelson WJ, Weis WI.
Science. 2011 Mar 11;331(6022):1336-9.

A fundamental characteristic of metazoans is the formation of a simple, polarized epithelium. In higher animals, the structural integrity and functional polarization of simple epithelia require a cell-cell adhesion complex that contains a classical cadherin, the Wnt-signaling protein β-catenin and the actin-binding protein α-catenin. We show that the non-metazoan Dictyostelium discoideum forms a polarized epithelium that is essential for multicellular development. Although D. discoideum lacks a cadherin homolog, we identify an α-catenin ortholog that binds a β-catenin-related protein. Both proteins are essential for formation of the epithelium, polarized protein secretion, and proper multicellular morphogenesis. Thus, the organizational principles of metazoan multicellularity may be more ancient than previously recognized, and the role of the catenins in cell polarity predates the evolution of Wnt signaling and classical cadherins.

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2 responses to “More Epithelial Nudging

  1. Hey Mike,
    NIce find. Its always +1 for you haha. Nice prediction. I have been out of the loop with things that have been going on due to teaching and going to school myself. I have been hearing there have been some interesting findings with the origin of life research. Is there any validity to that? Do you have any posts about it? Hope all is well!

  2. Hi Gore. Good to hear from ya! No, I have not heard of any interesting findings with the origin of life research. But then I don’t follow it that closely. My OOL postings are found here: https://designmatrix.wordpress.com/tag/ool/

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