Back to our roots

@article{Pilcher2005BackTO,
  title={Back to our roots},
  author={Helen R. Pilcher},
  journal={Nature},
  year={2005},
  volume={435},
  pages={1022-1023}
}
It was cold and clammy, but it changed the rules of life for ever. Helen Pilcher goes in search of the ancestor of all animals.Meet the ancestorSponges are the nearest living relatives of the first multicellular animal, a batch of single-celled organisms that came together in the ocean 600 million years ago. They have an immune system, signalling pathways and various cell types. By comparing the biology of the sponges with that of today's single-celled and complex animals, geneticists are… 

Paleoclimate and evolution: emergence of sponges during the neoproterozoic.

TLDR
These studies confirmed the view that the sponges evolved between two epochal ice times, 710-680 Ma (Sturtian glaciation) and 605-585 Ma (Varanger-Marinoan ice age), a period which allowed evolution to proceed but resulted also in a mass extinction of most animal taxa, with the exception of the Porifera.

The stem cell concept in sponges (Porifera): Metazoan traits.

  • W. Müller
  • Biology
    Seminars in cell & developmental biology
  • 2006

Effect of Bacterial Infection on Stem Cell Pattern in Porifera

TLDR
It is shown that after exposure to the endotoxin LPS (lipopolysaccharide) a differential gene expression occurs, leading to an upregulation of the gene encoding perforin and a concomitant down-regulation of noggin, a stem cell marker, which suggests that in response to bacterial infection the number of stem cells in sponges decreases.

Life as a Cosmic Phenomenon: 2.The Panspermia Trajectory of Homo sapiens

TLDR
It is argued that the current evolutionary status of Homo sapiens as well as its future trajectory is circumscribed by evolutionary processes that were pre-determined on a cosmic scale – over vast distances and enormous spans of cosmic time.

The unique invention of the siliceous sponges: their enzymatically made bio-silica skeleton.

TLDR
It is proposed that the key innovation that allowed the earliest metazoans to form larger specimens was the enzyme silicatein, crucial for the formation of the siliceous skeleton.

Formation of giant spicules in the deep-sea hexactinellid Monorhaphis chuni (Schulze 1904): electron-microscopic and biochemical studies

TLDR
It is suggested that, in the Hexactinellida, the growth of the spicules is mediated by silicatein or by a silicatesin-related protein, with the orientation of biosilica deposition being controlled by lectin and collagen.

Sustainable Exploitation and Conservation of the Endemic Lake Baikal Sponge (Lubomirskia baicalensis) for Application in Nanobiotechnology.

TLDR
The application of molecular biological and cell biological techniques has allowed an insight into the richness of the genomic regulatory systems of L. baicalensis, which dominates Lake Baikal's littoral-zone benthos and is a reference animal for other endemic sponges of this area, such as in the Tuva region.

Giant basal spicule from the deep-sea glass sponge Monorhaphis chuni : synthesis of the largest bio-silica structure on Earth by silicatein

TLDR
Experiments suggest that the spicules function in vivo as a nonocular photoreception system, endowing it with unusual optophysical properties, which are superior to those of man-made waveguides.

Genetic, biological and structural hierarchies during sponge spicule formation: From soft sol-gels to solid 3D silica composite structures

TLDR
This article attempts to overcome the frontiers in the understanding of the different levels of hierarchies, genetic, biological and structural, and to contribute towards the fabrication of new bioinspired functional materials.

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