Certain Protein Hormones

The Purification and Properties of Certain Protein Hormones Bacon F. Chow... 

The interactions between immune and inflammatory cells are mediated in large part by certain proteins, called lym-phokines, or interleukins (IL), that are able to promote cell growth, differentiation, and functional activation. Interleukins resemble hormones, which also function as intercellular messengers. In contrast to hormones, however, they are secreted by isolated cells rather than discrete glands. Several interleukins have been described each has unique biological activities as well as some that overlap with the oth-... 

Radioimmunoassay (RIA) of steroid hormones, a rapidly maturing branch of biochemistry, forms the subject of a monograph.The method depends upon the ability of certain proteins to bind steroids selectively and reversibly ... 

The major cell types of the adrenal medulla and extra-adrenal paraganglia include the catecholamine-synthesizing cells and the supporting or sustentacular cells. ° Both catecholamines and catecholamine-synthesizing enzymes have been demonstrated in the former cells with immunofluorescent techniques in frozen sections and immunoperoxidase techniques in paraffin-embedded material.The catecholamine-synthesizing cells typically exhibit positivity for a variety of generic NE markers and are variably positive for certain peptide hormones. Sustentacular cells, in contrast, are positive for S-100 protein. ... 

Among the common macromolecules that vertebrate cells internalize by receptor-mediated endocytosis are cholesterol-containing particles called low-density lipoprotein (LDL) the iron-binding protein transferrin many protein hormones (e.g., insulin) and certain glycoproteins. Receptor-mediated endocytosis of such ligands generally occurs via clathrin/AP2-... 

Lectins, proteins with highly specific carbohydrate-binding domains, are commonly found on the outer surface of cells, where they initiate interaction with other cells. In vertebrates, oligosaccharide tags read by lectins govern the rate of degradation of certain peptide hormones, circulating proteins, and blood cells. 

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