COMING BACK TO LIFE

REBIRTH

NAME: ANWESHA BANERJEE

TECHNO INDIA UNIVERSITY

ACKNOWLEDGEMENT

I would like to thank my professor Upasana Datta 

( Dept of Oceanography), for providing me the opportunity to present such a innovative task, that required imagination and hard work to complete this presentation.I would like to thank you for providing me the opportunity to learn new things about paleontology , Anthropology and history of earth. Learning about evolution and extinction of Dinosaurs was exciting and knowledgeable.

DINOSAURS

During the “Mesozoic Era”- an era of reptiles , there lived huge animals called Dinosaurs . The largest dinosaurs were over 100 feet (30 m) long and up to 50 feet (15 m) tall (for example–Ultrasauros,Argentinosaurus).The smallest dinosaurs, like Compsognathus, were about the size of a chicken. Most dinosaurs were in-between.There were lots of different kinds of dinosaurs that lived at different times.Some walked on two legs (they were bipedal), some walked on four (they were quadrupedal). Some could do both.Some were speedy (like Velociraptor), and some were slow and lumbering (likeAnkylosaurus).Some were armor-plated, some had horns, crests, spikes,or frills.Some had thick, bumpy skin, and some even had primitive feathers. [1]

DINOSAURS (contd.)

Dinosaurs went extinct about 65 million years ago (at the end of the Cretaceous Period), after living on Earth for about 165 million years. If all of Earth time from the very beginning of the dinosaurs to today were compressed into 365 days (1 calendar year), the dinosaurs appeared January 1 and became extinct the third week of September. (Using this same time scale, the Earth would have formed approximately 18.5 years earlier.) By comparison, people (Homo sapiens) have been on earth only since December 31 (New Year's eve). The dinosaurs' long period of dominance certainly makes them unqualified successes in the history of life on Earth .[2]

Most theories pertaining to this extinction are based on climate change, perhaps brought on by volcanism, lowering sea level, and shifting continents or even asteroid hitting the earth. But hundreds of other theories were developed, some reasonable but others rather far-fetched (including decimation by visiting aliens, widespread dinosaur "wars", and "paläoweltschmertz" the idea that dinosaurs just got tired and went extinct). It was often popularly thought that the evolving mammals simply ate enough of the dinosaurs' eggs to drive them to extinction.[3]

DINOSAUR DNA

Dinosaurs became extinct about 65millions years ago, but the search for their DNA has continued , for there is a glimmer of hope that may be one day dinosaur DNA may be isolated and the once gigantic beasts could be brought back to life .There is a problem to this , that is, the half life of DNA is 521 years [4].so according to known knowledge, biochemically it is impossible to extract DNA from a 65 million years old DNA sample with the help of existing technology.Most of the isolated dinosaur DNA are contaminated by other microorganisms or environmental factors .But in 2005 Mary Schweitzer and colleagues announced that they had found remnants of blood vessels in a thigh bone from Tyrannosaurus. Four years later, Schweitzer and coauthors described other soft tissue tidbits from the hadrosaur Brachylophosaurus. These weren’t fresh flesh. They had been altered over the course of time. Nevertheless, they seemed to retain some original soft tissue and revealed some details of the small and the squishy within saurians.[5],[6].

DINOSAUR DNA (CONTD.)

And now, just in time for the release of Jurassic World, (THE MOVIE) , Sergio Bertazzo, Susannah Maidment, and colleagues have offered a look at possible 75 million year old dinosaur blood cells. [7]The researchers didn’t pop the champagne on first sight of the microscopic structures. There were other possible explanations. Perhaps someone had accidentally bled on the fossil while it was in storage, for example. But through visual and biochemical investigations, the researchers were able to rule out human contamination. Additional studies will hopefully test the idea, but, for now, there’s a good chance that the scrappy bones at the center of the study really do preserve some degraded dino blood.[5]This wasn’t an isolated find. Out of eight dinosaur bones the researchers examined, they found some kind of soft tissue structure – be it blood cells, collagen fibers, or unknown carbon-rich structures – in six of them. This came as a shock. The bones were fragments. The sort of scrap curators are ok with paleontologists using for “consumptive analysis” because they’re unremarkable and often unidentifiable beyond the skeletal element. If these humble fossils could preserve the remains of soft tissues, Bertazzo and coauthors wondered, what about fossils that are heralded as exceptionally-preserved?

EXTRACTION OF DNA

Dinosaur DNA can be mainly extracted from dinosaur fossils. Fossils are preserved samples of beings that lived thousands or millions of years ago , in an intact form.The fossils provides bones, from these bones or shards of bone some DNA can be extracted(as preserved connective tissues or blood vessels) as seen in earlier experiments by Bertazzo and Schweitzer.

EXTRACTION OF DNA FROM SAMPLE

[8]

AMPLIFICATION OF DNA

The extracted DNA have to be amplified for further studies .This amplification is done by the help of Polymerase Chain Reaction , in a thermal cycler or a PCR machine.

POLYMERASE CHAIN REACTION

AMPLIFIED DNA(UPTO 30-35 CYCLES)

DNA SEQUENCING

SIMILARITY SEARCH

Similarity search is one of the fundamental element during reconstruction of the life of dinosaurs, that is to find if there are any beings on earth today whose genetic make up is similar to those that lived millions of years ago.After sequencing the DNA sequences can be matched in databases like NCBI, GENBANK, EMBL,DDBJ. Similar sequences can help us determine the connection and evolutionary model of dinosaurs to the animals we see today roaming in front of our eyes. Similarity search is mainly done by tools available today, like BLAST(Basic Local Alignment Search Tool).After similarity search evolution models can also be created by using Multiple Sequence Alignment (MSA) by the help of Clustal Softwares(Clustal W, Clustal Omega , Clustal W2 and so on.),T-COFFEE, MUSCLE and so on.

DNA SEQUENCE OF DINOSAUR FROM NCBI (GENBANK)

RESULT OF BLAST (BASIC LOCAL ALIGNMENT SEARCH TOOL)

MSA BY THE HELP OF CLUSTAL W2 SOFTWARE [10]

PHYLOGENETIC TREE HELPS TO MAKE A TENTATIVE ASSUMPTION OF THE EVOLUTIONARY MODEL OF THE DINOSAUR BEING STUDIED**NOT ONLY DNA SAMPLE BUT PROTEIN SAMPLES TOO CAN BE USED TO ESTABLISH ANCESTORY OF ANCIENT ANIMALS TO THAT OF , ANIMALS THAT ARE ALIVE TODAY.**

EVOLUTION

All animals have evolved from a ancestor ,now to remodel the ancestor it is important to find the animal which is a direct descendant of that ancestor .

In case of Woolly Mammoth(Mammuthus) ,mainly found in the Artic regions . It has been said by the anthropologists and paleontologists that mammoths before they became extinct, differentiated into two major groups (i) The African elephant (Loxodonta africana) and (ii) the Asian elephant (Elephas maximus) [11]

EVOLUTION (CONTD.)

Pterodactylus (meaning "wing finger") was a small, flying reptile that lived during the time of the dinosaurs.

It was not a dinosaur, but type of extinct, flying reptile (a pterosaur) that lived during the late Jurassic period. Fossils have been found in Tanzania, England, France, and Germany. This reptile lived during the late Jurassic period on lake shores. It reproduced by laying eggs.

Pterodactylus was originally named Ptero-Dactyle by Cuvier in 1809 and was Latinized by Rafinesque in 1815. [13]

Birds did not evolve from pterodactylus,But bats and pigeons are said to have Convergent evolutionary relationship to this flying reptile. It is also said that present day Drosophila melanogaster may also share some evolutionary characteristics of this flying reptile. [ 12]

Extracted DNA from samples of dinosaurs can be transferred via vectors or by vector-less (direct)method to multipotent cells(eggs of female) and then placed into a closely related species(into the uterus). Then they are allowed to grow and after the required amount of gestation period , baby dinosaurs will be born.

This method is called Cloning

The basic procedure is :Extraction of dinosaur DNA from fossils . The DNA is transferred to a enucleated egg of a donor female of the related species .The egg is transferred to a surrogate mother , where it will be fertilized by a male.After the required time of gestation period baby dinosaurs will be born

MAKING BABY DINOSAURS!

DIRECT TRANSFERVECTOR-MEDIATED

TRANSFER

ElectroporationParticle Bombardment(biolistics)Micro-injectionLiposome mediated transformationPEG mediated DNA transferDEAE mediated DNA transferCalcium-Phosphate co-precipitation mediated transfer.Silicon-Carbide fibre mediated transformation

Adeno-associated DNA transfer DNA –molecular conjugatesHuman artificial chromosomes.Lipoplexes(liposome mediated DNA transfer)

DNA TRANSFER TECHNIQUES

EXAMPLES OF DNA TRANSFER TECHNIQUES

MICRO-INJECTION

ELECTROPORATIONBIOLISTICS

NEW LIFE : WOLLY MAMMOTHDNA extracted from fossils are amplified

by PCR. Then the DNA is transferred to

a enucleated eggs cell of either a Asiatic elephant or African

elephant , since they have evolutionary

relationship.

The eggs are transferred to a

surrogate mother, then fertilized by a

male elephant, The fertilized

grow inside the surogate mother.

After the required

amount of time

(gestation period)Baby

Mammoth will be born

NEW LIFE : PTERODACTYLUS

Pterodactylus fossil

Extracted DNA from fossils is amplified by PCR, then

it is transferred to a enucleated egg cell of a

Bat or Drosophila melanogaster.

The egg is then transferred to a surrogate mother womb where it is

fertilized by the donor sperm by the male .

Baby “Pterodactylus“ will be born from the surrogate mother.

REFERENCES

[1] http://www.cmw.co.za/wool/clip_advice/dinosaurs.txt[2] http://pubs.usgs.gov/gip/dinosaurs/extinct.html[3]http://paleobiology.si.edu/dinosaurs/info/everything/why.html[4] https://www.icr.org/article/7160/[5] Schweitzer, M., Wittmeyer, J., Horner, J., Toporski, J. 2005. Soft-tissue vessels and cellular preservation in Tyrannosaurus rex. Science. 307, 5717: 1952-1955. doi: 10.1126/science.1108397[6]http://phenomena.nationalgeographic.com/2015/06/16/scrappy-fossils-yield-possible-dinosaur-blood-cells/[7] Bertazzo, S., Maidment, S., Kallepitis, C., Fearn, S., Stevens, M., Xie, H. 2015.Fibres and cellular structures preserved in 75-million-year-old dinosaur specimens. Nature Communications. doi: 10.1038/ncomms8352[8] http://www.icr.org/article/dinosaur-DNA-research-tale-wagging/[9] http://www.ncbi.nlm.nih.gov/[10] http://www.ebi.ac.uk/Tools/msa/clustalw2/[11] http://www.DNAdarwin.org/casestudies/10/FILES/MammothSG2.0.pdf[12] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2278091/[13] http://www.enchantedlearning.com/subjects/dinosaurs/dinos/Pterodactylus.shtml