Survivin, a unique member of the family of inhibitors of apoptosis (IAP) proteins, orchestrates intracellular pathways during cell division and apoptosis. Its central regulatory function has inspired several approaches that target survivin for cancer therapy. Analyses in early-branching Metazoa so far propose an exclusive role of survivin as a chromosomal passenger protein, whereas only later during evolution the second, complementary antiapoptotic function might have arisen, concurrent with increased organismal complexity. To lift the veil on the ancestral function(s) of this key regulatory molecule, a survivin homologue of the phylogenetically oldest extant metazoan taxon (phylum Porifera) was identified and functionally characterized. Additionally, new components of the innate defense sentinel in sponges were also identified. This new prototypes could represent a very efficient defense mechanism and may correspond to a new family of intracellular sensing protein, forming a subclass of pattern recognition receptors (PRR).

This digital document is a journal article from Palaeogeography, Palaeoclimatology, Palaeoecology, published by Elsevier in 2005. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
Palaeobiogeographical correlations based on poriferan and cnidarian taxa are proposed between the Iberian Peninsula and other basins for the Pennsylvanian, especially the North American Midcontinent. The available data indicate that poriferan and cnidarian diversity in the Iberian Peninsula was highest during the upper Carboniferous, and particularly during the Moscovian. A comparison using Dice's Coefficient shows a great similarity between the Iberian and North American fossil assemblages during this time, suggesting that the marine connection between the Palaeotethys Sea and the Panthalassan Ocean stayed open through the Moscovian, delaying the complete collision of Euramerica and Gondwana until the Kasimovian.