The key to the mammalian genome

Ongoing research into how the mammalian genome works could lead to major advances in livestock production, according to CSIRO Livestock Industries' researcher, Dr Brian Dalrymple.

,p>"By studying genome components called non-coding RNA, new information is captured and scientists are provided with a much clearer understanding of the biological complexity of the genome," Dr Dalrymple says.

Any RNA molecule that is not translated into a protein is classified as a non-coding RNA (ncRNA).

Dr Dalrymple says while most research to date has concentrated on genes coding for proteins, scientists are only now beginning to discover the large number and diversity of ncRNAs that exist.

"Current findings suggest the mammalian genome may contain twice as many ncRNAs as protein coding RNAs, indicating that ncRNAs may play a much more significant role than previously thought," he says.

In conjunction with their ncRNA investigations, researchers are studying a biological phenomenon called RNA interference (RNAi) - a process that allows specific genes in the cells of plants and animals to be 'switched off', or 'silenced'.

ncRNA molecules such as micro-RNAs (miRNAs) are important molecules in the gene silencing pathway " controlling gene expression during significant biological processes.

The CSIRO Livestock Industries team is working closely with the University of Queensland's Professor of Molecular Biology, and Institute for Molecular Bioscience Director, Professor John Mattick. Professor Mattick's research focus has been on the role of introns and ncRNAs as a hidden regulatory network controlling the development of mammals and other complex organisms.

The team's work indicates that discernible variations between individuals and species are largely due to ncRNA.

"At CSIRO Livestock Industries we are currently identifying and annotating ncRNAs in the bovine genome as part of an international project," Dr Dalrymple says.

"We've found that the complement of ncRNA in the bovine genome is similar to that in the human genome."

"By understanding how ncRNA works, we may be able to learn why there are differences between animals, such as why some animals are more susceptible than others to disease," he says.

Many important production traits in livestock animals may involve ncRNA molecules.

"Learning more about ncRNA may help us to identify genes that control traits such as growth efficiency, muscle development and milk composition; and to breed disease resistant animals."

"Most importantly, ncRNA let's us see the bigger picture," Dr Dalrymple says.

RNAi is a key component of CSIRO's biotechnology strategy, with the organisation holding an extensive and growing intellectual property portfolio in the area. CSIRO is developing products for, and with, the plant, livestock, aquaculture, animal biotechnology and biopharmaceutical industries.

Item provided courtesy of CSIRO