Catálogo de publicaciones - libros

Gene cloning requires, as an initial step, isolation of a specific gene encoding for the protein of interest. Locating and selecting a single gene among thousands of genes in a genome is not a simple task.

Fruit ripening involves biochemical and physiological changes that are primary factors influencing quality attributes, such as color, flavor and texture of the product. Tissue softening of fruits during ripening is the result of solubilization of the cell wall by a group of enzymes. One of the key enzymes is polygalacturonase (PG), functioning in the breakdown of pectin, a polymer of galacturonic acids that forms part of the structural support in cell wall.

Public concerns over the environmental and health effects of chemical pesticides have intensified the effort to search for alternatives. One of the attractive options is the use of biopesticides from microorganisms. The role of biopesticides in crop protection is not new. In fact the first such product, based on the insecticidal activity of , has been in commercial applications for more than 20 years. With the advent of recombinant DNA technology, scientists have produced transgenic crop plants engineered with insecticidal activity.

Herbicides act by inhibiting the function of a protein or an enzyme that is involved in certain vital biological possesses. For example, glyphosate and chlorosulfuron inactivate key enzymes in the biosynthesis of amino acids. Bromoxynil and atrazine interfere with photosynthesis by binding with the Q protein. Herbicides are therefore non-selective, because the biosynthetic pathways involved are present in both the weed and the crop plant. The effectiveness of a herbicide on the control of weeds depends on the differential uptake or metabolism of the herbicide between the weed and the crop.

The aquaculture industry in the U.S. produces ∼500 million pounds of processed fish yearly. Much of the improvement in fish farming has been done by traditional breeding methods. In the past two decades, there has been marked progress in employing recombinant DNA technology to produce transgenic fish with desirable traits, such as increased growth rate and disease resistance.

The early success of recombinant DNA technology relies heavily on the elucidation of the biological possesses at the molecular level in microbial systems. The first commercial application is realized in the microbial production of human insulin.

Among the 4000 known human genetic disorders, only a handful of disease-causing genes have been mapped. To locate a gene (say an average of 10,000 bp length) in the midst of a 3.2 billion bp chromosomal DNA is hardly a simple task.

There are more than 4,000 known inherited disorders. The majority of them have minimal effects, but a few causes physical and mental abnormalities that may be life threatening. Genetic diseases that are candidates for gene therapies include severe combined immunodeficiency, thalassaemia, and cystic fibrosis. Since these genetic diseases are each caused by a single defective gene, one potential treatment is to introduce a normal functional copy of the appropriate gene into the cell tissue that is affected. In effect, the normal (therapeutic) gene augments the defective gene in the patient. Gene therapy is not restricted to only treating genetic disorders. The general technology of transferring genetic materials into a patient is also applied to diseases such as cancer, AIDS, and cardiovascular diseases. Many of the approved clinical trials on gene therapy are for the treatment of diseases other than genetic disorders.

The delivery systems used in gene therapy are non-specific, infecting more than one cell type. In or manipulation this is not a serious problem. However, if therapy is to be developed, then cell specificity becomes desirable. In such a case, the gene carriers can be injected into the bloodstream much like administering many drugs.

DNA typing (fingerprinting, profiling) has become one of the most powerful tools for paternity/maternity testing, criminal identification and forensic investigation. It is also an important tool in evolutionary studies of relatedness in animals, insects, and microorganisms.