Evolution is driven by gene regulation

Aug 09, 2007

It is not just what’s in your genes, it’s how you turn them on that accounts for the difference between species — at least in yeast — according to a report by Yale researchers in this week’s issue of Science.

“We’ve known for a while that the protein coding genes of humans and chimpanzees are about 99 percent the same,” said senior author Michael Snyder, the Cullman Professor of Molecular Cellular and Developmental Biology at Yale. “The challenge for biologists is accounting for what causes the substantial difference between the person and the chimp.”

Conventional wisdom has been that if the difference is not the gene content, the difference must be in the way regulation of genes produces their protein products.

Comparing gene regulation across similar organisms has been difficult because the nucleotide sequence of DNA regulatory regions, or promoters, are more variable than the sequences of their corresponding protein-coding regions, making them harder to identify by standard computer comparisons.

“While many molecules that bind DNA regulatory regions have been identified as transcription factors mediating gene regulation, we have now shown that we can functionally map these interactions and identify the specific targeted promoters,” said Snyder. “We were startled to find that even the closely related species of yeast had extensively differing patterns of regulation.”

In this study, the authors found the DNA binding sites by aiming at their function, rather than their sequence. First, they isolated transcription factors that were specifically bound to DNA at their promoter sites. Then, they analyzed the sequences that were isolated to determine the similarities and differences in regulatory regions between the different species.

“By using a group of closely and more distantly related yeast whose sequences were well documented, we were able to see functional differences that had been invisible to researchers before,” said Snyder. “We expect that this approach will get us closer to understanding the balance between gene content and gene regulation in the question of human-chimp diversity.”

Source: Yale University

Explore further: Livingstone beetle specimens found after 150 years

add to favorites email to friend print save as pdf

Related Stories

Slimy fish and the origins of brain development

Sep 17, 2014

Lamprey—slimy, eel-like parasitic fish with tooth-riddled, jawless sucking mouths—are rather disgusting to look at, but thanks to their important position on the vertebrate family tree, they can offer ...

Recommended for you

22 elephants poached in Mozambique in two weeks

6 hours ago

Poachers slaughtered 22 elephants in Mozambique in the first two weeks of September, environmentalists said Monday, warning that killing for ivory by organised syndicates was being carried out on an "industrialised" ...

User comments : 0