Gene control research gets a boost

Article Abstract:

Scientists from five research teams in the US and Europe have made a significant advance in understanding how cells regulate their genes. They have isolated an important gene that controls synthesis of the TATA protein, a critical link in the biochemical communication network that achieves genetic transcription. Transcription is the process of reading the genetic code in DNA to make a complementary set of units in RNA. The RNA pattern becomes a mirror image of the DNA pattern, analogous to a negative or mold or matrix from which a positive is produced. The purpose of gene transcription is to build important proteins on a complex time schedule so that the organism, whether a virus or a mammal, can function. Turning genes on and off to manufacture the corresponding proteins regulates development of the embryo, directs the daily functioning of the adult organism, and, when the process malfunctions, may cause cancer and other diseases. Molecular biologists studying gene expression have had much success in understanding bacteria, but have found higher organisms much more difficult to analyze. In mammals, several regulatory proteins apparently must cooperate to turn a gene on, and these proteins have been hard to locate for further study. The TATA protein is critical because it binds to the gene first. After much difficulty isolating TATA, the gene for it in yeast has now been cloned (identically replicated). This brings scientists over an important hurdle. TATA was named for its molecular structure, an alternating sequence of the base molecules called thymine and adenine. TATA was discovered when scientists identified the protein that recognizes TATA, which they named transcription factor IID. The five research groups have now cloned the gene for transcription factor IID from yeast. A similar protein has not yet been isolated in mammalian cells. Advances in understanding yeast gene transcription should provide a foundation for deciphering the mammalian system.

Analysis, Genetic aspects, Fungi, Genetic regulation, Cloning, Gene expression, Genetic transcription, Transcription (Genetics)

---

Wider used of AIDS drugs advocated

Article Abstract:

United States health officials have released results of clinical trials showing that the drug AZT, 3'-azido- 3'deoxythimidine, can delay the development of AIDS in patients who are infected with the virus but do not show clinical symptoms. In patients with AIDS, there is a reduction in the number of T4 cells, cells of the immune system which are involved in the immune response against foreign entities, including the AIDS virus. Patients are no longer able to mount an immune response and therefore eventually develop the disease. In a study of 3,200 people, 1,300 had T4 immune cell counts that were very low. These people, who were infected but showed no symptoms of AIDS, were separated into three groups: those who were given high doses of AZT, those given low doses, and those given a placebo. The results indicated that patients were twice as likely to get worse if they were given a placebo rather than the active drug. In addition, the low dose was as effective as the high dose in slowing the progress of the disease, which would benefit those who experience side effects of the drug. This could also mean a reduction in the cost of treatment by as much as one half. The cost of treatment a year is now $7,000. With the finding that AZT can delay the symptoms of AIDS, nearly 600,000 people will be taking AZT. There is concern that the virus can become resistant to the drug treatment. However, the benefits of delaying the disease currently outweigh the risks. It must be remembered that AZT is not a cure for AIDS and other drugs are being developed.

Evaluation, Drug therapy, Zidovudine

---

NCI Team remodels key AIDS virus enzyme

Article Abstract:

Commercial researchers at Merck Sharp & Dohme Research Laboratories announced that they are now able to determine the three-dimensional shape of an enzyme that is essential to the AIDS virus. The original work was done by crystallography, but it has recently been challenged by several other laboratories, including the original researchers. The enzyme, a protease, is responsible for joining large proteins into larger polyproteins that are involved in the fabrication of the virus. The new data confirms that elements of the originally proposed structure are wrong, although only about 15 percent of the total structure appears to be in error. Corrections will be made to the original model. The structure of the protein is crucial if attempts to develop agents that recognize and block its action are to be developed. Methods such as this could be used to combat the virus directly. Similarly, detecting even small differences in the protein's structure may give researchers new understanding of its method of operation and therefore ways of producing drugs to combat it.

HIV (Viruses), HIV, AIDS research, United States. National Cancer Institute

Similar abstracts:

• Abstracts: Thought control: quality is a much about attitudes as procedures and systems. Train of thought
• Abstracts: Pressure to change. In the land of the dreamtime. Side splitting; jokes, ice water and magnetism can change your view of the world - literally
• Abstracts: Footprints to fill: Flat feet and doubts about makers of the Laetoli tracks. Fighting the darkness in El Dorado
• Abstracts: Recording CDs. Booster rocket blues. The shadow war
• Abstracts: Adam's rib? Broadening Viagra's reach may elucidate the physiology of female sexuality. Leaping leptin

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.