Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Dairy Drugstore

17.11.2006
Specialists of the All-Russian State Research Institute of Cattle Breeding have obtained transgenic animals, which give milk with the proteins participating in haemopoiesis. However, these are not ordinary transgenic animals, but somatic ones: the transgene is present not in every cell of the body, but only in the organ where it should work – in the udder.

The researchers started the effort for creation of somatic transgenic animals several years ago (InformNauka described these investigations in the material entitled “Transgenic Cows and Pigs” in 2002). Since then, they have obtained transgenic goats and specified influence of various factors on protein produce.

Utilization of transgenic agricultural animals as fermenters bodes well for pharmaceutical industry. However, the traditional method of getting them (when the DNA is introduced directly into the impregnated ovule) is inefficient. Only 1 percent of transplanted embryos turn out to be transgenic, and only 60 percent of transgenic animals provide at lease some amount of the required protein. Moreover, it would be clear who will give protein and how much of it several years after the DNA introduction when the transgenic ovule would turn into an animal of a proper age. Fortunately, there is a less lengthy and expensive way of gene transfer – the required gene is introduced directly into the mammary gland of a cow, goat or a sow.

Of course, the method is rather troublesome. First, the required gene should be built into the retrovirus’ genome, and the viral DNA should be introduced into the cell culture. Retroviruses possess a property very precious to genetic engineering – to survive in the cell, they must necessarily build their DNA into the cell’s chromosome.

The cells are reproducing and along with that they are producing new viral particles, and when they are introduced into the mammary gland, the viral particles penetrate the gland’s cells and build their DNA in the cellular genome. Thus, the mammary gland’s cells get the required gene and start producing the useful protein together with milk.

The researchers dealt with genes of two proteins participating in maturation of blood cells: erythropoietin and granulocyte-colony-stimulating factor. The maximum concentrations of these proteins in milk reached about 1,000 and 200 nanogram per milliliter, respectively. However, contemporary technologies allow to educe proteins from milk at ten times lower concentrations (only 25 nanogram per milliliter).

Practically all laboratory animals synthesized the required proteins during the entire period of lactation. However, the quantity of protein in milk changes from day to day. The first third of lactation is more productive than the two following ones. The researchers have determined that the highest possible production of proteins requires that gene constructions should be introduced into the mammary gland of cows in the 4th –6th month of pregnancy, that of goats – in the 4th –5th month of pregnancy, and that of sows – during the last trimester of pregnancy. The maximum production of proteins was achieved with cows, but the average concentration of proteins turned out to be higher in the milk of goats and sows.

In the researchers’ opinion, they have developed a technology, which allows to get the highest quantity of industrially important protein from the milk of an animal as compared to other existing gene transfer methods. Although transgenic animals, obtained by this method, do not transmit the new gene to descendants, they efficiently produce biologically active proteins in required quantities.

Nadezda Markina | alfa
Further information:
http://www.informnauka.ru

More articles from Agricultural and Forestry Science:

nachricht Light green plants save nitrogen without sacrificing photosynthetic efficiency
21.11.2017 | Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign

nachricht Filling intercropping info gap
16.11.2017 | American Society of Agronomy

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New proton record: Researchers measure magnetic moment with greatest possible precision

High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons

The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

IceCube experiment finds Earth can block high-energy particles from nuclear reactions

24.11.2017 | Physics and Astronomy

A 'half-hearted' solution to one-sided heart failure

24.11.2017 | Health and Medicine

Heidelberg Researchers Study Unique Underwater Stalactites

24.11.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>