Molecular studies regulation

In early studies of the molecular weight-regulating efficiency of various olefins in the metathesis polymerization of cyclopentene, the results of... 

Steroid hormones regulate a very extensive assembly of functions in numerous corporal tissues. Estrogens, the steroid hormones to which the majority of this chapter is dedicated, regulate from basic functions related to reproduction, the development of the skeleton, the maintenance of arterial tension, or diverse nervous functions. The molecular studies on the mechanism of action of estrogens have set the foundations that will permit us to understand how they carry out such diverse functions in such dissimilar tissues as well as how some substances that act through the estrogen signaling pathway can exercise opposite functions in different tissues. In this respect, there are five facts of particular importance that constitute the central nucleus of this revision ... 

Progress has also been made in molecular studies of cytochrome P-450 monooxygenases that are known to play an important role in insecticide resistance. The cytochrome P-450 gene from the house fly has been cloned, which should enable studies of the genetic regulation of insect cytochrome P-450 and further elucidation of its role in insecticide resistance (fil)-... 

Molecular studies on various GDH s are now proceeding rapidly since elucidation of the primary structures of some of these enzymes. It is essential to note, however, that these enzymes vary not only in coenzyme specificity but also in other properties, e.g., induction and repression of synthesis by metabolites, regulation of activity by purine nucleoside di-and triphosphates, e.g., ADP, GDP, ATP, GTP, and other ligands, and in molecular properties. The successful isolation from some species of modified forms of the enzyme produced by mutant strains, particularly of Neurospora, now permits identification of residues important for maintenance of normal activity. 

Ethylene is amongst the best known plant hormones because of the extensive biochemical and molecular studies on its biosynthesis and its regulation. Ethylene is synthesized in both higher plants and microorganisms, but via different biosynthetic pathways. 

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