Taz - in the mouse!

funny pictures

PLoS ONE just published a very exciting paper - a regulatory sequence from the genome of a preserved Tasmanian wolf was inserted into a mouse and shown to have the same function:

Resurrection of DNA Function In Vivo from an Extinct Genome:

There is a burgeoning repository of information available from ancient DNA that can be used to understand how genomes have evolved and to determine the genetic features that defined a particular species. To assess the functional consequences of changes to a genome, a variety of methods are needed to examine extinct DNA function. We isolated a transcriptional enhancer element from the genome of an extinct marsupial, the Tasmanian tiger (Thylacinus cynocephalus or thylacine), obtained from 100 year-old ethanol-fixed tissues from museum collections. We then examined the function of the enhancer in vivo. Using a transgenic approach, it was possible to resurrect DNA function in transgenic mice. The results demonstrate that the thylacine Col2A1 enhancer directed chondrocyte-specific expression in this extinct mammalian species in the same way as its orthologue does in mice. While other studies have examined extinct coding DNA function in vitro, this is the first example of the restoration of extinct non-coding DNA and examination of its function in vivo. Our method using transgenesis can be used to explore the function of regulatory and protein-coding sequences obtained from any extinct species in an in vivo model system, providing important insights into gene evolution and diversity.

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i think its really a great step forward to see function of DNA from 100 year old fixed tissue was restored...very nice invivo validation of enhacer in this work......also shows the conservation of TF's and enhancer element are conserved in mice and extinct species of marsupials........many more to come i suppose.....