New progress in the study of paleoproteins from Pleistocene spotted hyena fossils in East Asia

  Recently, Dr. Rao Huiyun, Researcher Liu Jinyi, and Associate Researcher Zhang Zhi of the Institute of Spine Paleontology and Paleontology of the Chinese Academy of Sciences are Professor Yang Yimin of the University of Chinese Academy of Sciences, Professor Westbury of Nanxing University in Copenhagen and we and Associate Professor Shao Qing jobs. Through protein sequence and phylogenetic analysis, we will study the classification of East Asian spotted hyena fossils and possible gene exchange with existing species in Africa.

  CrocutaCrocuta is a species of Crocuta, currently distributed in sub-Saharan Africa. During the geological period, it almost occupied Eurasia and was called cave hyena. At present, the understanding of the origin and evolution of spotted hyenas is not uniform, and the results obtained through morphology, mitochondrial genes and nuclear genes are also different (Figure 1). However, most of the molecular data comes from Europe, but it has not been well studied in Asia. Only four sites can obtain valid DNA data, so we need to add more data.

  spotted hyena fossils are widely distributed in East Asia, living in Japan from the middle Prestosen to the early Pleistocene. At present, dozens of fossil groupers have been discovered and provided physical data for research. Some locations, such as Lingxian Cave (Uranium date\→ 99ka), are not sufficient for various ancient DNA analyses. The study was conducted in three locations in northern China (including Lingxian Cave), taking into account DNA storage limitations. Cave Hyena performs ancient protein analysis to obtain various endogenous proteins (Figure 2). A variety of enzyme digestion methods can increase the coverage of peptides. The coverage rate of type I collagen has exceeded 80%. Combined with database search and analysis of de novo sequences, multiple mutation sites in the cave hyena in East Asia were identified. This study obtained the ancient protein sequence of the cave hyena. It provides reference sequences for future related research and adds new molecular data of the cave hyena in East Asia. Phylogenetic analysis based on protein sequence shows that cave hyenas in East Asia are divided into two groups, one of which is composed of live spotted hyenas in North Africa. This is different from the nuclear gene results reflecting the East Asian results before 1.03 Ma. In northern Africa, there may be gene exchanges between cave hyenas and spotted hyenas. This study shows that ancient protein analysis has the potential for phylogenetic reconstruction, and molecular evidence can be found in a longer time frame and a wider range.

  Relevant research results have been published in the "Science Report". Research activities are organized by the National Natural Science Foundation of China, the Strategic Leadership Science and Technology Program of the Chinese Academy of Sciences (Class B), the Open Project of the National Institute of Contemporary Paleontology and Stratification, and the youth of the Chinese Academy of Sciences The Innovation Promotion Association was launched.