All of them are completed by the Chinese people, and the most complicated genome group ｜ Decoding naked oats "China core"

As a worldwide cultivation of 42 countries and regions of the five continents, oats are divided into two types: leather and naked oats. Among them, naked oats independence originated in my country and is widely planted, which is affectionately called "莜 其" by the Chinese.

On July 18, "Nature -Genetics" published six times the high -quality genome of naked oats on the line online, opening the door of the naked oats.

"This study was completed by the Chinese by themselves. In -depth research on Chinese -unique oat quality resources, I hope to firmly hold the quality resources in our own hands, and let the oats have more 'Chinese cores'." The country Ren Changzhong, chief scientist of the Oatmeal buckwheat industry technology system, Ren Changzhong, a researcher at the Baicheng Academy of Agricultural Sciences, who led the study.

The thesis reviewer believes that "the genome is one of the most complex genomes of all species sequencing so far" and "represents the major progress of plant genome, especially grain genome."

Naked oats (。). Interviewee confidence

Racing to travel with the world

Oats are rich in protein, unsaturated fatty acids, and soluble dietary fibers, which can meet people's requirements for dietary nutrition and health care at the same time.

Specific oatmeal seeds are tangible, and the leather is closely linked with seeds, and it is difficult to get rid of it after maturity. The naked oatmeal grains are naked grains, and the leather is particularly soft.

Compared with skin oats, the naked oatmeal processing technology is simpler, with higher protein and crude fat content, and amino acid composition is more balanced and highly valuable.

At present, the cultivation species of countries around the world are mainly skin oats. In my country, naked oats are planted. The main producing areas are concentrated in Inner Mongolia, Hebei, Shanxi, Qinghai, Gansu, Jilin, Shaanxi, Ningxia and Xinjiang. Among them, Inner Mongolia has the largest planting area, reaching more than 4 million acres.

In recent years, China's oat industry has developed rapidly at an annual output value of more than 20%.

"The nude trait of the oat seed grains is one of the important domesticated traits." Peng Yuanying, the first author of the paper and a professor of Sichuan Agricultural University, told the China Science News that as a six -fold crop, oats in biomass, vitality, and environmental changes to the environmental changes Adaptability has significant advantages, and it can play a unique role in responding to food security challenges.

Ren Changzhong, author of the thesis communication, believes: "China, as the origin and planting center of naked oats, has a unique competitive advantage of species of germ -quality chips. The processing of naked oats in China should be completed by the Chinese first, which enhances the competitiveness of the domestic oat industry. It is of great significance to ensure food safety and so on. "

However, oats are six -fold crops, which have the characteristics of large genome and high repeated sequence content, which leads to its genome test assembly into a world problem.

"10 years ago, foreign counterparts began to do genome sequencing for leather oats, but due to the difficulty, there was no result. Later, foreign countries from the United Kingdom, Germany, the United States, Australia, Sweden, Canada and other countries studying oats studied oats. Combined with scientists who have deciphered the Grand Maor and Wheat Genome Treasse to capture the problem of oatloburated. "Peng Yuanying said.

In our country, the team led by Ren Changzhong has long been engaged in oatmeal research and has accumulated rich experience. Especially in the past 20 years, Peng Yuanying's team and others have been focusing on the origin and evolution of oats species, laying a good foundation for the genome sequence of six times oats.

In 2018, with the support of the National Oatmeal buckwheat industry technical system and the National Natural Science Foundation of China, Sichuan Agricultural University -Jilin Provincial Academy of Agricultural Sciences of the Jilin Provincial Academy of Agricultural Sciences and the Institute of Genetics and Development Biology of the Chinese Academy of Sciences, Sichuan University, Xichang University, Xichang University, Xichang University, Xichang University The college, the Chinese Academy of Agricultural Sciences, and Wuhan Hope Biotechnology Co., Ltd., etc., officially launched the sequencing work of nude oatmeal base group.

This oatmeal research team composed of Chinese scientists is a joint team composed of oat researchers from other countries. "This adds a sense of urgency to our related work." Peng Yuanying said.

Break -off complex genome

The existing cultivation of oats has naturally hybridized and doubled in the long evolution. It forms four times from the twice body, and eventually doubles it to six times with three genomes containing A, C, and D.

The naked oatmeal group is composed of about 11 billion bases, and is distributed in 21 pairs of chromosomes in the nucleus 3 sub -genomic.

Its genome is huge and complicated, with a volume of about 40 times the rice genome, and about 87%of genomic DNAs are repeated sequences, which makes it difficult for its genome test assembly research.

So, how can we make a different approach and catch up with the foreign team that brings together the world's strongest scientific research forces?

Peng Yuanying told reporters that in response to the assembly problems caused by the composition of the six -fold oatyana genome and its high repeated sequence content, they chose high -accurate ultra -long sequencing technology and used the most likely four -fold body and duplex ancestor of oats to cultivate oats. As a reference, the genome was successfully completed.

The result of this time is based on the "three -pointers" of oats in the center of the naked oats origin.

Through the research on "three -pointers", the researchers drawn the molecular diagram of the 21 pairs of chromosomes of the oats genome, annotated that 120,000 protein encoding genes were annotated to obtain the high -quality reference genome map of naked oats.

After submission of the paper to "Nature", it was highly evaluated. A reviewer believes that the assembly and annotations of the genome, as well as the accompanying genome and heavy sequencing resources, have high quality. The "three -point three" genome has sufficient novelty because this genome is quite unique in his genetic status. Another reviewer said that the data and analysis provided by this work are highly novel and provide new insights for the evolution of large multi -twice genome.

One month later, the leather oatmeal genetic map jointly completed by foreign counterparts also contributed to "Nature".

Ren Changzhong said: "Our Chinese team held the pressure and completed the results of this research first."

Oatmeal research enters the age of genome

After obtaining a high -quality genome map, Peng Yuanying's most wanted to know the evolutionary process of oats. "How to evolve with oats, this has always been a scientific mystery." This is one of the themes she has studied over the years.

They chose species that can represent all genomic types of oats, combined with rice and wheat, etc., analyzed the evolutionary position of oats in major grain crops, and the origin and multiple times of oats from the entire genome level. History.

It was found that the differentiation between the oats and the wheat people occurred after the formation of the rice, and the relationship between the oats and the multi -flower black wheat grass was closer than that of the oats and the wheat.

Oatmeal species were produced about 8 million years ago.

And about 500,000 years ago, in the era of human old stone artifacts, six times the oats were multiplied by multiplied oats with AA genome and CCDD genome.

"In -depth understanding of the evolutionary history of oats will greatly promote penetration and breeding, and transfer the beneficial traits from the surviving wild -friendly species closest to oats to cultivating oats, which effectively promotes the selection of excellent breed of oats." Peng Yuanying said In the map, the breeding and genetic research of our naked oats will enter the fast track.

"We will be able to cultivate naked oats with specific traits and functions according to genetic information, such as improving the disease resistance of varieties; control the size of the seeds and increase the yield; Intake the effectively controlling cholesterol and diabetes with dietary fiber. "Ren Changzhong said.

Oats are threatened by illness during growth, the most serious of which is crown rust. The team identified 1,269 resistance genes in the 3 sub -genomic groups of six times oats.

Most resistance genes appear in the chromosomal end, and are located with the crown rust gene section known as oats, indicating that the oats reference genome constructed by the study can provide effective references for the positioning and cloning of oat disease -resistant genes.

They also conducted a full -genome correlation analysis of the cultivation of 659 sources and found a candidate gene to control the nude trait of oat seed grains.

The research team believes that the construction of oats reference genome, as the first step in the genome era, will make the whole genome of oats a possible selection of breeding and accurate breeding.

"We can now consider how to use modern breeding strategies, such as genome editing, to further improve and develop specific oats to meet the global demand for this healthy food and high -quality forage."

Next, the team will also combine the original research advantages to further carry out research on the origin, domestication and excellent genetic resources excavation and utilization of oats.

Source: "China Science News" (2022-07-19 1st edition of the news)

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