A computational analysis of the genomes of the papaya, poplar, grape, and a small flowering plant called Arabidopsis thaliana, has identified hundreds of 100-million-year-old non-coding DNA sequences shared between these plants.
These conserved non-coding sequences, discovered by an international group of biologists, are not genes, but are located in the promoters upstream of genes and are around 100 DNA base pairs in length. As the papaya, poplar, grape and Arabidopsis have evolved separately for around 100 million years, the fact that these DNA regions have been conserved suggests they play an important role in the plants’ development and functioning.
“We know that certain genes are conserved between species – but we also see that sequences outside of genes are conserved,” said senior author Dr. Sascha Ott of the University of Warwick’s Systems Biology Center. “The regions outside genes that we have discovered have been kept for millions and millions of years across four species. There must be a reason for this – if something has been around for so long it is probably useful in some way. We believe it may be because these regions have a very important role to play in how the plant develops and functions.”