Featured Research

from universities, journals, and other organizations

Scientists Use Long-Term Cultured Cells For Cloning

Date:
January 6, 2000
Source:
University Of Connecticut
Summary:
University of Connecticut scientists and Japanese colleagues who produced six genetically identical calves using cells taken from the ear of a prize bull in Japan, have announced that they cultured the cells for up to 3 months in vitro before using them for cloning.

STORRS, Conn. -- University of Connecticut scientists and Japanese colleagues who produced six genetically identical calves using cells taken from the ear of a prize bull in Japan, have announced that they cultured the cells for up to 3 months in vitro before using them for cloning.

In the rapidly evolving field of cloning technology, it has been believed that long-term culture of donor cells would compromise (if possible at all) their efficiency for cloning. But the UConn scientists say that long-term culture of donor cells may do just the opposite and also may make it possible to manipulate genetic modifications in the donor cells prior to cloning.

Their findings could have enormous implications in the cattle industry and in the future applications of cloning technology in biomedical research.

A paper describing the cloning technique used to produce the six calves will appear in the January 4th issue of the journal "Proceedings of the National Academy of Sciences." Dr. Xiangzhong (Jerry) Yang, head of the University of Connecticut's Transgenic Animal Facility and corresponding author of the article, says the researchers were surprised to find that donor-cells of long-term culture were capable to support embryo development and production of offspring.

"These findings are novel and unexpected," Yang acknowledged. "We have produced normal cloned calves from adult somatic cells after 2- or 3-months of continuous culture in vitro. In fact, we observed higher developmental rates for embryos derived from donor cells after long-term culture than those after short-term culture. The significance of this research should set the stage for future targeted gene manipulations of the donor cells prior to cloning."

The research is the result of a collaboration between the laboratories of Dr. Chikara Kubota of the Kogashima Cattle Breeding Development Institute in Japan and Dr. Yang's Animal Transgenic Facility at UConn.

In Japan, scientists hope to use cloning technology to improve the breeding of beef cattle to obtain animals with higher quality meat. While technology exists that allows scientists to alter the site-specific genetic makeup in mice, it is dependent on the manipulation of mouse embryonic stem (ES) cells which are not available in other species.

However, animal cloning using cultured somatic cells (cells other than reproductive cells), offers the possibility of targeted genetic manipulations as those performed in mice, but only if those somatic cells remain competent for cloning after prolonged culture.

"Long-term culture of somatic cells is essential for the possible targeted genetic manipulations of donor cells to create targeted genetically altered cells, tissues, organs and animals via cloning," explains Yang. "Live clones have been obtained from adult somatic cells in sheep, mice and cows, however these clones all came from donor cells after short in vitro culture which did not allow targeted gene manipulations."

Another related issue about cloning animals surfaced recently after a study questioned whether Dolly, the cloned sheep, was healthy as the DNA genetic material she was copied from is aging at the rate of the older sheep from which she was cloned.

Thus Yang and Kubota's research was conducted to test the cloning competence of somatic cells obtained from aged donor animals, particularly after those "aged" donor somatic cells were subjected to long-term cultures. These combinations would provide a very important model for studying the aging process.

The six cloned calves they produced came from the skin cells of a genetically elite, aged (17-year-old) Japanese Black cattle bull named "Kamitakafuku." Famous in Japan for their superior meat quality, Kamitakafuku has produced nearly 160,000 offspring.

In December 1997, Yang and Kubota (who recently was admitted to UConn as a doctoral student to study under Yang), collected skin cells from the ear of Kamitakafuku. These cells were then cultivated in a culture containing few nutrients "starving" the cells so they stopped dividing before they are used for cloning.

The researchers then transferred the nuclei carrying genetic information from the cultivated cells after 2 months, and placed them in unfertilized eggs whose nuclei had been taken out. The eggs were then implanted in the wombs of surrogate cows. The process was repeated with another set of cells after 3 months in vitro.

Four calves were born in December 1998 from cells cultured for two months (two of these calves are still alive); and two more cloned calves were born in February 1999 from three months culture.

The four surviving cloned bulls are named as Kamitakafuku-1,-2,-3 and -4 in Japanese. Their American names are Tommy, Andy, Timothy and Anthony, for TATA, or the name for the genetic control region in their DNA. These clones are now 10 months (Timothy and Anthony) and 1-year-old (Tommy and Andy), and appear normal as compared to their conventionally reproduced peers.

"Our research shows that cells of aged animals remain competent for cloning, and prolonged culture does not affect the cloning competence of adult somatic donor cells," said Yang. "And cloning whole animals with somatic cells as parents offer the possibility of targeted genetic manipulations in vitro."


Story Source:

The above story is based on materials provided by University Of Connecticut. Note: Materials may be edited for content and length.


Cite This Page:

University Of Connecticut. "Scientists Use Long-Term Cultured Cells For Cloning." ScienceDaily. ScienceDaily, 6 January 2000. <www.sciencedaily.com/releases/2000/01/000106083235.htm>.
University Of Connecticut. (2000, January 6). Scientists Use Long-Term Cultured Cells For Cloning. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2000/01/000106083235.htm
University Of Connecticut. "Scientists Use Long-Term Cultured Cells For Cloning." ScienceDaily. www.sciencedaily.com/releases/2000/01/000106083235.htm (accessed July 24, 2014).

Share This




More Plants & Animals News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Boy Attacked by Shark in Florida

Boy Attacked by Shark in Florida

Reuters - US Online Video (July 24, 2014) An 8-year-old boy is bitten in the leg by a shark while vacationing at a Florida beach. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Dogs Appear To Become Jealous Of Owners' Attention

Dogs Appear To Become Jealous Of Owners' Attention

Newsy (July 23, 2014) A U.C. San Diego researcher says jealousy isn't just a human trait, and dogs aren't the best at sharing the attention of humans with other dogs. Video provided by Newsy
Powered by NewsLook.com
Professor Creates Site Revealing Where People's Cats Live

Professor Creates Site Revealing Where People's Cats Live

Newsy (July 23, 2014) ​It's called I Know Where Your Cat Lives, and you can keep hitting the "Random Cat" button to find more real cats all over the world. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins