Featured Research

from universities, journals, and other organizations

Plant Gene Related To Cancer Treatment May Foster New Oncology Drugs

Date:
November 22, 2005
Source:
Purdue University
Summary:
Two proteins involved in the process that controls plant growth may help explain why human cells reject chemotherapy drugs, according to an international team of scientists.

Molecules in laboratory plants grown in the Purdue University horticulture greenhouses are helping cell biologist Angus Murphy unravel why human cells reject cancer drugs. (Purdue Agricultural Communication photo/Tom Campbell)

Two proteins involved in the process that controls plant growth may help explain why human cells reject chemotherapy drugs, according to an international team of scientists.

Related Articles


Researchers from Purdue University and Kyoto University in Japan have shown for the first time that proteins similar to multi-drug resistant proteins in humans move a plant growth hormone into cells, said Purdue plant cell biologist Angus Murphy. Because plant proteins called P-glycoproteins (PGPs) are closely related to human P-glycoproteins that impact chemotherapy effectiveness, discovery of methods to control the plant protein's activity may aid in development of therapies to reduce drug dosages administered to cancer patients, Murphy said.

Murphy is corresponding author of the study published in the November issue of Plant Cell. He also is corresponding author of a related article published in October's Plant Journal.

"Results of this research will give us a better idea of the functioning of the multi-drug resistance process in which human cancer cells reject anticancer treatments," Murphy said.

Results of the two studies suggest a previously unknown relationship between two protein families involved in this process, he said. Working together, the proteins apparently move molecules of the plant growth hormone auxin through cell walls. In humans, related proteins rid cells of toxins such as cancer drugs.

"The findings of these two studies have important implications for biomedicine because we now can identify the parts of these proteins that determine whether cells take up or throw off different molecules, such as cancer drugs," Murphy said.

In the Plant Journal study, Murphy and his collaborators at the University of Zurich showed for first time that PGP1, a P-glycoprotein from the commonly used experimental plant Arabidopsis, directly transports auxin out of plant cells and also out of yeast and mammalian cells. In the Plant Cell study, they found that other PGP proteins move auxin into cells.

"Auxin molecules essentially are pulled through the cell membrane by PGP transport proteins," Murphy said. "It's an energetic process that happens like pulling a rope through something sticky."

Both the multi-drug resistant PGPs in people and plants are part of a large family of proteins, called ATP-binding cassette (ABC) proteins, that act as delivery trucks to detoxify cells, send messages from cell to cell to influence biochemical reactions, and to regulate those reactions. The ABC proteins are so named because they must bind with ATP, the main cell energy source, in order to fulfill their mission.

The best known member of another class of transport proteins, PIN1, also may be a transporter, but appears to function primarily as an aide rather than the delivery truck for auxin transport, Murphy said. This finding revealed that PINs and PGPs may function together in long-distance auxin transport, according to the Plant Journal article. Named for the pin-shaped appearance of the mutant originally used to identify the gene that directs the activities of PIN1, these proteins are members of the major protein family, called facilators, that aid processes such as hormone transport.

Recent evidence suggests that teamwork between PGP and PIN proteins determines the direction auxin moves and, therefore, how the plant develops, Murphy said. In plants, shape, height and bending in response to light and gravity are largely determined by the direction and amount of auxin moving through their tissues.

Murphy and his collaborators on the Plant Journal study found that PGP1 and PGP19 move the hormone out of cells.

In the November Plant Cell report, Murphy's research team reported that another P-glycoprotein, PGP4, functions in the opposite direction, providing the boost needed to import the hormone auxin into cells and to increase the amount transported.

"With these two studies, we've shown for the first time that both the uptake and release of molecules are mediated by interaction between the PGP transporter proteins and PIN facilitator proteins," Murphy said.

Other researchers involved with the Plant Cell study were Joshua Blakeslee, Wendy Peer, Boosaree Titapiwatanakun, Anindita Bandyopadhyay, Srinivas Makam, Ok Ran Lee and Elizabeth Richards, all of the Purdue Department of Botany and Plant Pathology; Kazuyoshi Teraska and Fumihiko Sato of the Laboratory of Molecular & Cellular Biology of Totipotency, Kyoto University, Japan; and Kazufumi Yazaki of the Laboratory of Plant Gene Expression, Kyoto University. Teraska, Blakeslee and Titapiwatanakun each contributed equally to the research project and as authors of the journal paper.

The U.S. National Science Foundation; the Ministry of Education, Culture, Sports, Science and Technology of Japan; and the Uehara Foundation of Kentucky provided support for this research.

On the Plant Journal paper, Markus Geisler of the Basel-Zurich Plant Science Center, University of Zurich, and Blakeslee were co-lead authors and contributed equally to the research; Murphy was corresponding author; and Enrico Martinola, of the University of Zurich, was senior author. The U.S. National Science Foundation and the Swiss National Science Foundation provided funding for the study.


Story Source:

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


Cite This Page:

Purdue University. "Plant Gene Related To Cancer Treatment May Foster New Oncology Drugs." ScienceDaily. ScienceDaily, 22 November 2005. <www.sciencedaily.com/releases/2005/11/051122183706.htm>.
Purdue University. (2005, November 22). Plant Gene Related To Cancer Treatment May Foster New Oncology Drugs. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2005/11/051122183706.htm
Purdue University. "Plant Gene Related To Cancer Treatment May Foster New Oncology Drugs." ScienceDaily. www.sciencedaily.com/releases/2005/11/051122183706.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Reuters - Innovations Video Online (Dec. 21, 2014) A team of scientists led by Danish chemist Jorn Christensen says they have isolated two chemical compounds within an existing antipsychotic medication that could be used to help a range of failing antibiotics work against killer bacterial infections, such as Tuberculosis. Jim Drury went to meet him. Video provided by Reuters
Powered by NewsLook.com
Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Monarch Butterflies Descend Upon Mexican Forest During Annual Migration

Monarch Butterflies Descend Upon Mexican Forest During Annual Migration

Reuters - Light News Video Online (Dec. 19, 2014) Millions of monarch butterflies begin to descend onto Mexico as part of their annual migration south. Rough Cut (no reporter narration) Video provided by Reuters
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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