Mammals regulation

Weltzin, J. F., Archer, S., and Heitschmidt, R. K. (1997). Small-mammal regulation of vegetation structure in a temperate savanna. Ecology 78, 751-763. 

The prolactin receptor, PER, which regulates milk production in mammals, belongs to the same receptor class as the growth hormone receptor. In addition to binding the hormone prolactin, PER also binds and is activated by growth hormone. The extracellular domain of PER forms a very stable 1 1 complex with growth hormone in solution this complex has been crystallized and its structure determined (Figure 13.21). We shall compare this structure with the 1 2 complex of the same hormone with GHR. 

Mammals, fungi, and higher plants produce a family of proteolytic enzymes known as aspartic proteases. These enzymes are active at acidic (or sometimes neutral) pH, and each possesses two aspartic acid residues at the active site. Aspartic proteases carry out a variety of functions (Table 16.3), including digestion pepsin and ehymosin), lysosomal protein degradation eathepsin D and E), and regulation of blood pressure renin is an aspartic protease involved in the production of an otensin, a hormone that stimulates smooth muscle contraction and reduces excretion of salts and fluid). The aspartic proteases display a variety of substrate specificities, but normally they are most active in the cleavage of peptide bonds between two hydrophobic amino acid residues. The preferred substrates of pepsin, for example, contain aromatic residues on both sides of the peptide bond to be cleaved. 

Friedman JM, Halaas JL (1998) Leptin and the regulation of body weight in mammals. Nature 395 763-770... 

In contemporary societies replete with various industries and automobiles, NO (NO, N02, and N03) has been recognized to be one of the important factors responsible for air pollution. Only two decades ago, NO was found to be an essential molecule that regulates cellular/molecular functions in mammals. NO is also enzymatically synthesized in nonmammals, invertebrates, and yeasts. Therefore, the origin of NO may date back to the birth of life arising from single cell organisms living around 3-billion years ago. 

Nelson, W.J. (1992). Regulation of cell surface polarity from bacteria to mammals. Science 258, 948-955. 

Coppola D.M. and Vandenbergh J.G. (1987). Induction of a puberty-regulating chemosignal in wild house mouse population. J Mammal 68, 86-91. 

McClintock M. (1983). Pheromomal regulation of the ovarian cycle enhancement, suppression and synchrony. In Pheromones and Reproduction in Mammals (Vandenberg J.G., ed.). Academic Press, New York, pp. 113-150. 

Figure 1. Hierarchy of control of gene expression. A total of about 50,000 to 100,000 genes are necessary to encode a mammal, most of which encode housekeeping, structural component, or terminal differentiation gene products. Transcription factor genes regulate expression of the lower-level genes and are in turn controlled by other upper-level transcription factors.

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