Featured Research

from universities, journals, and other organizations

Researchers Model Embryo Implantation And Tumour Metastasis In Fruit Flies

Date:
March 12, 2004
Source:
University Of Toronto
Summary:
A research team at The Hospital for Sick Children (Sick Kids) led by Dr. Howard Lipshitz has discovered that a protein previously linked to mammalian embryo implantation, as well as tumour metastasis, plays similar roles in fruit fly development.

TORONTO (March 11, 2004) - A research team at The Hospital for Sick Children (Sick Kids) led by Dr. Howard Lipshitz has discovered that a protein previously linked to mammalian embryo implantation, as well as tumour metastasis, plays similar roles in fruit fly development. This research is reported in the featured article in the March 9, 2004 issue of the scientific journal Current Biology.

"We were surprised to find such high evolutionary conservation of the structure, expression and function of these proteins - called integrin and basigin - between flies and mammals, whose ancestors diverged over 500 million years ago," said Dr. Lipshitz, a senior scientist and head of the Developmental Biology Research Program at Sick Kids and a professor of Medical Genetics and Microbiology at the University of Toronto. "In mammals, if you mutate the basigin protein, the embryo can't implant, probably because the extraembryonic membrane cannot maintain close contact with the wall of the uterus. In flies, if you mutate the proteins, two different extraembryonic membranes fail to maintain contacts and the result is death of the embryo."

While fruit flies develop quite differently from humans, there is remarkable conservation of fundamental processes and the genes that control them. For example, two thirds of all known human disease genes are also present in fruit flies. "This cheap and tractable genetic system serves as a 'living test tube' in which to figure out the fundamental molecular basis of human development and disease," added Dr. Lipshitz, also the Canada Research Chair in Developmental Biology.

Dr. Bruce Reed, a research associate in Dr. Lipshitz's lab and the paper's lead author, serendipitously discovered the fruit fly basigin protein two years ago, while doing live imaging studies with the state-of-the-art confocal microscopes in the Sick Kids Research Institute's Imaging Facility acquired with support from the Canada Foundation for Innovation and the Ontario Innovation Trust. Looking for a marker that would enable him to see live cells - particularly those of the extraembryonic tissues - as they change their shape and motion, Dr. Reed saw the molecules that he would eventually identify as basigin. The molecules were attached to the membrane of the yolk sac, a placenta-like structure that feeds the fruit fly embryo.

When integrin and basigin molecules were depleted, the extraembryonic membranes could not establish close contacts, equivalent to mammalian embryos not implanting. In addition, Dr. Reed found that membrane contact was required for survival of the tissues. In mutants, the tissues fall apart and die. This has an exciting connection to tumour cell metastasis in humans. "When a tumour metastasizes, cells in fact have to decide to leave it and invade other tissues," said Dr. Reed. "Here, in flies, you have cells leaving the tissue, but their fate is instead, to die. All you need is something that prevents cells from dying when they leave the tissue and they would immediately become 'immortal' and invasive."

"If you think about how the placenta has to be formed it is an invasive process and must be regulated so that it doesn't behave like a metastatic tumour," said Dr. Reed. "The implication is that there is a fine balance between the good kind of invasion and the bad kind."

In mammals, basigin is expressed on the surface of 60 per cent of human gliomas, a type of nervous system tumour, and prior research has shown that the higher the level of expression of basigin the more invasive the tumour. Eventually, the research team may be able to model the molecular basis of metastasis using flies. The next steps involve the detailed study of the molecular biology of the tissue contact process and the 'metastatic' behaviour of the cells as they leave the tissue in mutants.

Other members of the research team included Dr. Ronit Wilk of The Hospital for Sick Children and Dr. Frieder Schφck of McGill University. This research was supported by the National Cancer Institute of Canada, the Canada Research Chairs Program, and The Hospital for Sick Children Foundation.

###

The Hospital for Sick Children, affiliated with the University of Toronto, is Canada's most research-intensive hospital and the largest centre dedicated to improving children's health in the country. Its mission is to provide the best in family-centred, compassionate care, to lead in scientific and clinical advancement, and to prepare the next generation of leaders in child health. For more information, please visit http://www.sickkids.ca.


Story Source:

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


Cite This Page:

University Of Toronto. "Researchers Model Embryo Implantation And Tumour Metastasis In Fruit Flies." ScienceDaily. ScienceDaily, 12 March 2004. <www.sciencedaily.com/releases/2004/03/040312085559.htm>.
University Of Toronto. (2004, March 12). Researchers Model Embryo Implantation And Tumour Metastasis In Fruit Flies. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2004/03/040312085559.htm
University Of Toronto. "Researchers Model Embryo Implantation And Tumour Metastasis In Fruit Flies." ScienceDaily. www.sciencedaily.com/releases/2004/03/040312085559.htm (accessed July 31, 2014).

Share This




More Plants & Animals News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) — Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com
Concern Grows Over Worsening Ebola Crisis

Concern Grows Over Worsening Ebola Crisis

AFP (July 30, 2014) — Pan-African airline ASKY has suspended all flights to and from the capitals of Liberia and Sierra Leone amid the worsening Ebola health crisis, which has so far caused 672 deaths in Guinea, Liberia and Sierra Leone. Duration: 00:43 Video provided by AFP
Powered by NewsLook.com
At Least 20 Chikungunya Cases in New Jersey

At Least 20 Chikungunya Cases in New Jersey

AP (July 30, 2014) — At least 20 New Jersey residents have tested positive for chikungunya, a mosquito-borne virus that has spread through the Caribbean. (July 30) Video provided by AP
Powered by NewsLook.com
Xtreme Eating: Your Daily Caloric Intake All On One Plate

Xtreme Eating: Your Daily Caloric Intake All On One Plate

Newsy (July 30, 2014) — The Center for Science in the Public Interest released its 2014 list of single meals with whopping calorie counts. 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