Researchers have found that a protein necessary for sperm fusion with oocytes is also a component of a protein virus that invades the host, and this finding will help prevent and treat parasitic diseases such as malaria.
The same is true of sexual reproduction and viral infection. The latest study suggests that both processes require the same protein: HAP2, which is used to facilitate the seamless fusion of the two cells, such as sperm cells and egg cells, or Virus and cell membrane fusion. This protein is widespread in viruses, unicellular protozoa and many plants and arthropods, suggesting that this protein may have appeared early in the history of the earth.
The discovery, published in the Feb. 23 issue of the journal, reveals a new concept of sexual evolution that serves as a nearly common biochemical "key" factor that helps the two cell membranes blend into one, promoting genetic material Of the reorganization, which is a necessary step for sexual reproduction.
"Our findings suggest that nature has a limited number of ways to help cell cells fuse into a single cell," said William Snell, professor of cell biology and molecular biology at the University of Maryland.
"This protein is still used by many of the Earth's organisms for sexual reproduction, and that is, dengue and card card virus into the human cells used in the protein," Snell that this protein "in a".
Snell and his colleagues analyzed HAP2 protein in single cell green algae (<EM> Chlamydomonas reinhardtii </ EM>). Although HAP2 is not present in fungi or vertebrates (such as humans), it is common in single-cell protozoa, plants, and arthropods, and the Snell team has previously found that HAP2 is a biological organism that has this protein Essential elements, but the molecular mechanism is not clear.
On this basis, the researchers used the complex computer analysis tool to compare the amino acid sequence of HAP2 in the above green algae with the sequence of the known virus fusion protein. The results have found surprising similarity, especially in areas known as "fusion loops" that can help viral proteins successfully invade cells. If HAP2 functions like a viral fusion protein, Snell makes it inference that interfering with the formation of HAP2 fusion loops can block the ability of its fusion cells.
Surely, when Snell et al. Changed an amino acid in the HAP2 fusion loop, the protein completely lost its function. Sperm and egg cells can still be bonded together (determined by other proteins), but can not complete the final fusion of the cell membrane. Similarly, when the researchers add antibodies that cover the HAP2 fusion loop, the cells can not fuse.
"These results make us very excited because it supports our proposed new model of HAP2 functionality," Snell said, "but also need to take the three-dimensional structure of the HAP2 protein to see if it is similar to the virus fusion protein."
Snell contacted a structural biologist at the Pasteur Institute: Felix Rey, who studied the structure of Chlamydomonas reinhardtii HAP2 using X-ray crystallography. Rey's findings suggest that HAP2 does have the same function as dengue and zombie virus fusion proteins. Rey said, "Chlamydomonas sp. HAP2 protein folded with the same virus protein," which means that from a simple amino acid chain to build the three-dimensional structure of the protein molecular folding process.
HAP2 appears to be essential in the process of cell fusion in a variety of organisms, including pathogenic protozoa, invasive plants and destructive pests. Up to now, known HAP2 has the same key amino acid in the fusion loop region. Therefore, HAP2 can be used as vaccine, disease treatment and other new targets for prevention and control.
"If we were able to develop a vaccine that attenuated the integration of Plasmodium falciparum, it would be a huge step forward." Our findings suggest a new strategy for malaria parasite HAP2. "
prev:PNAS: the best breakthrough in the spread of cancer(2017-02-23)
next:The first use of CRISPR to achieve special stem cell adult gene repair(2017-02-27)