What is in this article?:
- AgriLife Research scientists work with RNA silencing and plant stem cells
- Off-switch for genes
- Increased fruit production is goal of RNA work.
- Switching genes off is a factor.
- National Science Foundation grant helps Texas A&M with study.
Research on controlling the stem cells of plants could eventually lead to learning how to make them produce more fruit, seed and leaves, according to Dr. Xiuren Zhang, Texas AgriLife Research scientist and professor with the Texas A&M University department of biochemistry and biophysics.
Results of a nearly three-year project led by an AgriLife Research team headed by Zhang was published in Cell, one of the most cited scientific peer-review journals in the world.
"Working with the shoot meristem area, we may (eventually) control fruit and seed yield or plant mass by manipulating the development and maintenance of plant stem cells. We can also engineer plant shapes by doing this," Zhang said.
In plants, the shoot meristem area is composed of undifferentiated cells, which means they can be programmed by the plant to become various structures -- leaf, stem, branches flower, etc. -- much as mammalian stem cells can be programmed to produce different organs, he said.
The team worked with Arabidopsis, a plant also known as rock cress, which is related to cabbage and mustard. Arabidopsis is often used for studying plant biology because it is the first plant to have its entire genome sequenced.
Previous studies had shown that the Arabidopsis gene known as argonaute 10, or simply AGO10, plays a critical role in regulating meristem cell development.
Arabidopsis has 10 AGO genes, and it was known that AGO10 is involved in various biological processes such as meristem development and proper leaf formation, but by exactly what mechanism it performed these roles was not clear, Zhang said.
"However, although the genetic functions of AGO10 have been described, the molecular mechanism by which it regulates SAM (shoot apical meristem) development remained unknown," Zhang wrote in the Cell article. "Here we demonstrate that AGO10 specifically interacts with miR166/165."
The abbreviation miR166/165 refers to microRNA, a type of small RNA molecule that regulates gene expression, Zhang explained. MicroRNAs are deceptively simple in structure, often only about 20 bases in length, whereas regular RNA may be composed of hundreds or thousands of bases.