Biosynthesis peptide hormones

Numerically the largest group of signaling substances, these arise by protein biosynthesis (see p. 382). The smallest peptide hormone, thyroliberin (362 Da), is a tripeptide. Proteohormones can reach masses of more than 20 kDa—e.g., thyrotropin (28 kDa). Similarities in the primary structures of many peptide hormones and proteohormones show that they are related to one another. They probably arose from common predecessors in the course of evolution. 

The biosynthesis of peptide hormones and proteohormones, as well as their secretion, is controlled by higher-order regulatory systems (see p. 372). Calcium ions are among the substances involved in this regulation as second messengers an increase in calcium ions stimulates synthesis and secretion. 

Another technique that is utilized to help ensure that label is incorporated into the pheromone is to apply the precursor at the same time as pheromone biosynthesis activating neuropeptide (PBAN). PBAN is a peptide hormone that regulates pheromone biosynthesis in most, but not all, moths. So, first it must be demonstrated that PBAN regulates pheromone production. In the case of the cabbage looper,... 

The biosynthesis of the protein hormones involves the synthesis of molecular forms larger than the polypeptide secreted from the cell [4,5]. The genetic information in DNA which codes for peptide hormones is discontinuous with intervening se-... 

The number of reports suggesting that peptides in plants play an important role as hormone-like molecules has been increasing in recent years. Most of the biologically active peptides are biosynthesized from precursors by processing and/or specific modification, as was the case with PSK and CLE peptides. In order to develop peptide hormone research, it is necessary to accurately determine the chemical structures of mature peptides. Once the chemical structures of the peptides are determined, it is expected that research will further expand, focusing on biosynthesis, receptors, and signal transduction. 

We used the Bombyx adult heads as a source of PTTH (5) along with bombyxins (formerly 4K-PTTH, insulin-related peptides possessing PTTH activity in the brainless pupae of Sarnia cynthia ricini) (6), eclosion hormone (7), melanization and reddish coloration hormone (8) and pheromone biosynthesis activating neuropeptide (9). All these peptide hormones have been isolated and characterized. 

The allatostatins are a family of brain peptides which rapidly and reversibly inhibit juvenile hormone biosynthesis in isolated insect corpora allata. Five allatostatic peptides from brains of the cockroach Diploptera punctata have now been structurally identified (i 2 our unpublished results), their size ranging from octapeptide to octadecapeptide. The currently identified allatostatins all possess the consensus C-terminal sequence (L/V)YXFGL-amide, which has no significant homology with other known peptides. It is likely that they are released locally from nerve terminals within the glands (3). 

Wegrzyn J, Lee J, Neveu JM, Lane WS, Hook V. Proteomics of neuroendocrine secretory vesicles reveal distinct functional systems for biosynthesis and exocytosis of peptide hormones and neurotransmitters. J. Proteome Res. 2007 6 1652-1665. 

Voet, D. and Voet, X G. (1995) Biochemistry, 2nd edition, Chaps. 24, 30 and 34. (Amino add metabolism, protein biosynthesis, blood clotting, peptide hormones and neurotransmitters). 

The biosynthesis of the glucocorticoids and mineralocorticoids are regulated by independent mechanisms. The glucocorticoids, such as cortisol, are biosynthesized and released under the influence of peptide hormones secreted by the hypothalamus and anterior pituitary (adenohypophysis) to activate the adrenal cortex (the... 

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