Properties and Genetic Control

The Human Hemoglobins Their Properties and Genetic Control Harvey A. Itano... 

JONSSON, L.M.V., AARSMAN, M.E.G., POULTON, J.E., SCHRAM, A.W., Properties and genetic control of four methyltransferases involved in the methylation of anthocyanins in flowers of Petunia hybrida. Planta, 1983,160, 174-179. 

Kamsteeg, J., Van Brederode, J., Hommels, C.H. and Van Nigtevecht, G. (1980) Identification, properties and genetic control of hydroxycinnamoy 1-coenzyme A antho-cyanidin 3-rhamnosyl (1 6) glucoside, 4 -hydroxycinnamoyl transferase isolated from petals of Silene dioica. Biochem. Physiol. Pfanzen, 175, 403-11. 

The genes encoding the polypeptide backbones of a number of mucins derived from various tissues (eg, pancreas, small intestine, trachea and bronchi, stomach, and salivary glands) have been cloned and sequenced. These studies have revealed new information about the polypeptide backbones of mucins (size of tandem repeats, potential sites of N-glycosylation, etc) and ultimately should reveal aspects of their genetic control. Some important properties of mucins are summarized in Table 47-8. 

In one way or another, all these changes involve chemistry, the study of the composition, properties, and transformations of matter. Chemistry is deeply involved in both the changes that take place in nature and the profound social changes of the past two centuries. In addition, chemistry is central to the current revolution in molecular biology that is now exploring the details of how life is genetically controlled. No educated person today can understand the modern world without a basic knowledge of chemistry. 

In a previous section, data and plots were given showing the rapid rise in consumption and production of manufactured fibers at the expense of natural fibers. The principal reason for this has been the wide range of manufactured fiber variants that can be produced from a single fiber-forming polymer. The wide range of polymers available, each with its particular properties, adds yet another dimension. This is not to say that there is only one type of cotton, wool, silk, or asbestos fiber there are many varieties of natural fibers, but their supply is limited by natural factors such as climate and genetics. The relative availabilities of manufactured fiber types can be altered by controlled chemical-process... 

The genetic material controls the properties and functions of the cell and detcT-mines, for example, whether the cell is a brain cell, a liver cell, a blood cell, or even a cancer cell. The genetic material controls the location of the eyes in the body, how fast we grow and how much we weigh, and, in some cases, personality traits. 

These differences between BN and LEW rats in susceptibility to metal-induced autoimmunity and nephropathy are associated with intrinsic differences in the immune system of these two strains. Indeed, from an immunological point of view, the balance between "type 1" (Thl/Tcl) and "type 2" (Th2/Tc2) cells is opposite in BN and LEW rats. BN rats are susceptible to "type 2"-mediated immunological disorders, to which the LEW strain is resistant. Conversely, "type l"-mediated organ-specific autoimmune disease are easily induced in LEW, but not in BN rats [155]. These immunological features depend on inherent properties of T lymphocytes. In vitro and in vivo studies have shown an inherent bias in T lymphocytes (CD4 and CDS) from BN and from LEW rats to produce respectively "type 2" (IL-4, IL-5, IL-13) and "type 1" (IFN-y cytokines [156-158]. The difference in susceptibility to metal-induced autoimmunity and nephropathy of BN and LEW strains provides a unique tool to study their genetic control. 

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