We Discussed so many times on this blog about the need of appropriate model system to under take the challenge provided by the genomic era and expansion of integrative disciplines like evo devo,which requires researchers to adopt a more integrative approach while choosing model organisms.Another important point which should be considered in choosing model systems is their phylogenic position ,so that they might serve as a complement to existing model systems in reconstructing evolutionary history.

DP2.1.1.6X.14.H
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The starlet anemone “Nematostella Vectensis” is becoming an increasingly important model system for …

So after a small gap (mainly due to hectic schedule with flies and biochemical experiments in my lab) i am back with some more interesting details on homeobox genes and this time we take a look into homeobox repertoire of “Sponges-The pore bearers”.Remember some days back we discussed about Homeobox genes in most primitive organism on earth “Ctenophores” and now we go a bit ahead in tree of life to gain further insights from demosponge Amphimedon queenslandica genome sequence.
The first conclusive evidence for presence of antennapedia like Homeobox genes in …

Researchers from Uppsala University, Karolinska Institute, and the University of Chicago, have determined that there are hundreds of biological differences between the sexes when it comes to gene expression in the cerebral cortex of humans and other primates.
These findings, published June 20th in the open-access journal PLoS Genetics, indicate that some of these differences arose a very long time ago and have been preserved through evolution of primates. These conserved differences constitute a signature of sex differences in the brain.

New exquisitely preserved fossils from Latvia cast light on a key event in our own evolutionary history, when our ancestors left the water and ventured onto land. Swedish researchers Per Ahlberg and Henning Blom from Uppsala University have reconstructed parts of the animal and explain the transformation in the new issue of Nature.
It has long been known that the first backboned land animals or “tetrapods” – the ancestors of amphibians, reptiles, birds and mammals, including ourselves – evolved from a group of fishes about 370 million years ago during the …

Here is some information about two interesting meetings coming up one in developmental biology and another evo devo in Frannce and Belgium respectively.

“Frontiers in Developmental Biology” meeting
The French and Japanese Societies for Developmental Biology are organising on 13 – 17 September 2008 in Giens, on the French Mediterranean coast, a meeting entitled “Frontiers in Developmental Biology”.
The meeting will explore how the most recent technological and conceptual advances in the fields of genomics, systems biology, bioinformatics, imaging and modelling can complement more traditional developmental biology studies.
Organizers : Patrick Lemaire (IBDML Marseille) …

Homology or conservation(sequence and function) forms crux of Evolution and today we look into two aspects where the conservation is really amazing.Firstly we talk about NK4 / tinman’s (NKx 2.5 Humans) association with Heart or Dorsal vessel and then move to Micro RNA’s in Hox complex of flies and Vertebrates.

Tinman/NK4 or NKx 2.5 :
Tinman is broadly expressed in mesoderm of flies and later restricted to cardiac mesoderm where it plays vital role is Heart Development. Nk genes were first discovered in flies and later found in almost all metazoans. Tinaman/NK4 …

Notch Signaling:
Notch signaling pathway is implicated in various developmental process in all eumetazoans,required at different developmental stages in various tissues.In Drosophila,Notch pathway is activated by binding of ligands Serrate and Delta which results in cleaving of Notch intracellular domain.Once cleaved the intra cellular domain is free to enter nucleus and there with the help of suppressor of Hairless (Su(H) and mastermind forms a activator complex.Notch receptor with co activators (Su(H) and mastermind activates downstream target genes in context depending manner.
Hairless another protein in flies, acts as a negative regulator …