DNA double-stranded fracture repair gene cloning was successful

recently, Plant Physiology published online Yangzhou University School of Agriculture Professor Yu Hengxiu team in rice successfully cloned the DNA double strand fracture (DSB) repair-related gene OsATM. This study analyzes the role of OsATM in the process of rice subtracting and provides a theoretical basis for further exploration of the molecular mechanism of rice breeding.
, the author of the paper, said that DNA, as a genetic material, maintains the integrity and stability of its molecular structure, which is of great significance to cell survival and normal physiological function. In the daily growth environment of plants and animals, a variety of external and endogenous factors, including ionizing radiation and cell metabolites, can cause different forms of DNA damage. Among them, DNA double-stranded fracture is the most serious form of damage, seriously threatening the normal life activities of cells.
ATM protein, as a sensory molecule for DNA damage, plays a central role in the repair of DNA double-stranded fractures. However, the sex parent cells of mammalian atm mutants have dedated division stagnation and apoptosis, so it is not possible to fully analyze the role of ATM protein in the de-detracting process. Plant subtracting lacks the test point mechanism for repair of this damage, so it is the ideal system for studying related proteins. As early as 2003, the study of amorphic mustard has proved that AtATM plays an important role in the process of subtracting division, but its relationship with detracting division is not resolved.
hengxiu team obtained three allied mutants of OsATM by sterilization mutants through map cloning. Abnormal adhesion and chromosomal fragments of non-ionosomal chromosomes appear in Osatm pollen parent cells. The team demonstrated through fluorescent in-place hybridization and immuno-location analysis that the pairing and association of omogeneic chromosomes in mutants were normal.
OsDMC1 is the key protein in the search for subtracting splores, and the lack of function of this protein causes the commost chromosomes to fail to join, showing the esopic form of the monoploric body. The team found that in Osdmc1 Osatm dual mutants, gregorian chromosomes cannot be joined, but there is still severe adhesion between chromosomes and large numbers of chromosomal fragments. This suggests that Osatm decompression of the abnormality of the split chromosome does not depend on the same-origin recombination process, and OsATM may play a role in the dna double-stranded fracture repair pathway parallel to the same-origin recombination.
after solibulic cells produce DNA double-stranded fracture damage, the histoprotein H2AX attached to the damaged bit is rapidly phosphorylated by ATM (called γ-H2AX) to initiate the damage response. As a result, wild cells were able to observe a large number of γ-H2AX signals, which were barely observed in Osatm, after the rice root tip was treated with the DNA double-stranded fracture injury induced reagent Bollymycin.
further observations by the researchers found that γ-H2AX signals were still observed in Osatm pollen mother cells, and that there was no significant difference between the number of signal points and the wild type. The results show that there may be a mechanism difference in phosphateization between rice soy cells and reproductive cellSH2AX. (Source: Li Chen Wang Yifan, China Science Journal)
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