Ma Runlin's research group in the School of Life Sciences has made important progress in the evolution of ruminants

Professor Ma Runlin’s research team from the School of Life Sciences, University of Chinese Academy of Sciences has made important progress in the study of the animal’s Major Histocompatibility Complex (MHC) structure, initially revealing that the MHC of all ruminants, including cattle and sheep, is in the Class II region There is a large segment of autosomal insertion, which divides the original intact Class II into IIa and IIb, and is accompanied by the production of new DY genes that regulate immune cells
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Research suggests that the chromosome inversion event is likely to originate from a chromosomal inversion (Crossing Over) that occurred in the germ cells of the last common ancestor of ruminants.
The inversion promoted the prosperity and expansion of ruminants in the earth's biosphere, resulting in herbivorous ruminants.
The huge groups of animals play an important role in maintaining the ecological balance of the natural food chain
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The research results were recently published in the International Frontiers in Immunology journal "Frontiers in Immunology"
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MHC encodes a large class of immune defense-related proteins and regulatory factors, and is the most critical genetic basis for humans and all mammals to resist the infection and pathogenicity of various microorganisms
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Ruminants use rumen microbes to effectively transform the solar energy fixed in the forage, which plays a key role in maintaining the food chain of higher carnivores on the earth
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Ma Runlin’s research team confirmed in previous studies that there is a chromosome inversion of about 18 Mb in the MHC region of cattle and sheep, causing the MHC class II region to be divided into two subregions II a and II b
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The DY gene specific to ruminants is located on the edge of inversion and is highly expressed in dendritic cells
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However, whether the inversion is universal in ruminants and its significance to the evolution of ruminants is still unknown
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Hypothesis of chromosomal inversion of the ancestors of Cetacea Artiodactyla

Ma Runlin’s research group used high-throughput sequencing technology to sequence 47 BAC clones covering the MHC segment of the antelope, and obtained a molecular sequence of 3,224,151 bp in length, annotated 150 coding genes, 50 tRNA genes and 14 A non-coding RNA gene

The paper was published online in Frontiers in Immunology on February 25, 2020