Paleoproteomic profiling recovers diverse proteins from 200yo human brains

Summary

Left cerebral hemisphere of an adult male buried at the site of the former Blackberry Hill Hospital (Bristol, UK). The surface of the brain's visible convolutions is stained red with iron oxides. Credit: Alexandra Morton-Hayward A new method developed by researchers at the Nuffield Department of Medicine, University of Oxford, could soon unlock the vast repository of biological information held in the proteins of ancient soft tissues. The findings, which could open up a new era for paleobiological discovery, have been published in PLOS ONE. From brains and muscles, to stomach and skin—preserved soft tissues can offer unique insights into the past, and the lives of individuals. But up to now, this treasure trove of information has been largely inaccessible to science. In the new study, the team led by postgraduate researcher Alexandra Morton-Hayward (University of Oxford) developed the first robust method for extracting and identifying proteins from ancient soft tissues, then demonstrated its capability on archaeological human brain samples. "Until now, studies on ancient proteins have been confined largely to mineralized tissues such as bones and teeth," says Morton-Hayward. "But the internal organs—which are a far richer source of biological information—have remained a 'black box' because no established protocol existed for their analysis. Our method changes that." A key hurdle was finding an effective way to disrupt the cell membranes to liberate the proteins. After testing ten different strategies on samples from 200-year-old human brains excavated from a Victorian workhouse cemetery, the team discovered that urea (a major component of urine) successfully broke open the cells, liberating the proteins within. Alexandra Morton-Hayward, forensic anthropologist and doctoral candidate at the University of Oxford, holds the two cerebellar hemispheres of a 200 year-old brain, preserved in formalin. Credit: Graham Poulter. Alexandra Morton-Hayward, forensic anthropologis...