SCIENTIFIC EDUCATIONAL CENTER science idea

Chinese scientists have isolated perfectly preserved cartilage cells from a 125 million-year-old dinosaur. They contain nuclei with remnants of organic molecules and chromatin. Such studies, according to scientists, bring science closer to sequencing the DNA of ancient "lizards".

The preservation of cell nuclei in long-extinct organisms is considered a rare and exceptional phenomenon. Due to the fragility of nucleic acids, such nuclei are quickly destroyed after the death of the animal (sometimes within a few hours). However, such structures are periodically found and described, especially in ancient plants.

Not so long ago, chromatin filaments were first discovered in the fossilized vertebrate cartilage of a duck-billed dinosaur (Hypacrosaurus stebingeri). This time, scientists from Linyi University and the Institute of Vertebrate Paleontology and Paleoanthropology (China) have isolated perfectly preserved cells of distal articular cartilage from a dinosaur that lived in northeastern China 125 million years ago-Caudipteryx. It was an animal the size of a peacock with long feathers on its tail.

A piece of cartilage was removed from the right femur. Paleontologists first decalcified it, and then used various chemical methods for analysis. It turned out that the cells were mineralized by calcification after the death of the dinosaur. This probably helped them to survive so well. The researchers also found that some of the animal's cells looked healthy even after death, while others, sick and porous, began the process of fossilization even during the dying of the creature.

Among other things, the authors used a chemical substance — hematoxylin, a natural dye obtained from the essential extract of the campesha tree. With his help, paleontologists managed to color the nuclei of some dinosaur cells in purple. The preservation of the find turned out to be so unique that experts were able to examine both some original biomolecules in cells and chromatin filaments.

Such studies, according to scientists, bring science closer to the successful sequencing of dinosaur DNA. After all, it is believed that DNA molecules of this age simply cannot be preserved. A study by Chinese paleontologists gives hope that this is not so or not quite so, since Caudipteryx cells are not completely fossilized and still contain remnants of organic molecules. It's up to the "little ones— to find out if they have preserved some biological information and DNA remnants.

The article was published in the journal Communications Biology
PHOTO: Reconstruction of caudipteryx at the time of death © Zheng Qiuyang

Source: naked-science.ru, sci-dig.ru