Researchers from Yale University School of Medicine confirmed in a comparative genomics study that the active genes in human development limbs are regulated by thousands of sequences, and these sequences have the potential to promote the evolution of human hands and feet. The research, published online in the July 3 issue of Cell, did not depict the exact genetic mechanism that controls the development of human limbs, but provided scientists with the first genome-wide study of candidate research factors view.
James P. Noonan, a senior author of the study, a researcher at the Kavli Institute, and an associate professor of genetics, said: "We now have a list of components that may clarify these biological changes.
The unique characteristics of human limbs seen early in human development indicate that genetic changes are the basis for the activation of these traits in human embryos. Previous studies have compared the human genome with the genomes of other primate species to identify genetic sequence changes that may occur during human evolution. In 2008, Noonan and colleagues used this method to identify a human gene regulatory sequence and confirmed that it displays human-specific activity in developing limbs, which may contribute to the evolution of human thumb. However, at the time, the researchers did not know how many of these elements were present in the human genome.
To answer this question, the Noonan team began to look for differences in the activity of these regulatory sequences throughout the genomes of humans, macaques, and mice during limb development.
The research team used the biochemical marker H3K27ac, which is known to recognize these sequences, to construct an active gene regulatory sequence map in the developmental limbs of each species. The analysis results show that although the genetics of limb development in the three species are roughly similar, there are a small number of regulatory sequences: 13% of promoters and 11% of enhancers are particularly active in the limbs of human embryos. These sequences may have been active since the evolutionary divergence between humans and macaques about 25 million years ago.
Noonan said he plans to transfer some of these human-specific regulatory elements to the mouse genome and investigate what aspects of human limb development they might control.
"Understanding the evolutionary mechanism of human traits is very difficult because we have no idea where important genetic changes might be. Now we are working on this, and we have obtained some experimental tools to identify the organisms that these changes may cause. Scientific effects. Our research also provides a road map for understanding other human-specific traits that occur during development, such as the increase in brain size and complexity. "
boys backpack
Mianyang Crossing Cross-Border E-Commerce Co., Ltd. , https://www.wycybag.com