The protein, known as AtRGS1, regulates the process of cell proliferation by turning the G protein complex off. A report of the discovery appears in today's (Sept. 19) issue of the journal Science.
The protein was discovered in Arabidopsis thaliana, a wild mustard weed. Completion of the Arabidopsis genome sequence in 2000, the first for a higher plant, made it ideal for molecular investigation such as this. In addition, this small weed has homologues or counterparts of many important human proteins, including some involved in diseases, such as cystic fibrosis and cancer.
"We have identified the first and a truly novel regulator of G protein signaling, or RGS signaling protein, in Arabidopsis," said Dr. Jin-Gui Chen, senior research associate in the department of biology and the report's first author. "This finding can be considered a breakthrough in G protein signaling."
Roughly 800 types of these cell receptors exist in human cells, said plant cell biologist Dr. Alan M. Jones, a senior study author and professor of biology in UNC's College of Arts and Sciences.
"These are the molecular targets for about half of the drugs in use today worldwide, which account for $9 billion a year in sales."
Teasing out the complexities of how signals are transduced into action within cells also holds implications for agriculture. "The new RGS protein's function in the G protein signaling pathway may give us a handle on how fast plant org
Contact: Leslie Lang
University of North Carolina School of Medicine