Hetero-oligomers

APP is a type-I transmembrane protein that is part of an evolutionarily conserved protein family, including the amyloid precursor-like proteins 1 (APLP1) and 2 (APLP2). APP and APLPs are functionally redundant and form homo- and hetero-oligomers. The absence of the A 3 sequence in the APLPs underlines the importance of APP that can only give rise to the A 3 species. Decreasing the formation of soluble A 3... 

Rocheville, M, Lange, DC, Kumar, U, Patel, SC, Patel, RC and Patel, YC (2000) Receptors for dopamine and somatostatin formation of hetero-oligomers with enhanced functional activity. Science 288(5463) 154-157. 

With this protocol nine different primary amines (Fig. 7.6) were used to generate different 9-residue homo-oligomers, one 20-residue homo-oligomer and one 9-residue hetero - oligomer. 

Harvengt P, Vlerick A, Fuks B, Wattiez R, Ruysschaert J-M, Flomble F. 2000. Lentil seed aquaporins form a hetero-oligomer which is phosphorylated by a Mg2+-dependent and Ca2+ regulated kinase. BiochemJ352 183-190. 

Daniels DJ, Kulkarni A, Portoghese PS. Bivalent ligands designed to probe receptor heterodimers/hetero-oligomers pharmacological evidence for interactions between opioid receptor types. International Narcotic Research Conference, Monterey, CA, 2002 S47. 

Fig 1311 Hypothetical model for ligand interactions with the opioid receptor (Only k-8 hetero oligomers shown, but scheme also applies to the complex) The interactions between the... 

Gibbons, W. A., Hughes, R. A., Charalambous, M., et al. (1990) Synthesis, resolution and structural elucidation of lipidic amino acids and their homo- and hetero-oligomers. Liebigs Ann. Chem. 12, 1175-1183. 

K. Das, R.Y. Lewis, P.E. Scherer, and M.P. Lisanti, The membrane-spanning domains of caveolins-1 and -2 mediate the formation of caveolin hetero-oligomers. Implications for the assembly of caveolae membranes in vivo, J. Biol. Chem., 1999, 274, 18721-18728. 

In several systems, natural antagonistic ligands have been identified that bind on the extracellular side to the receptor and inhibit receptor activation. Furthermore, certain tissues express naturally occurring receptor variants that are deficient in tyrosine kinase activity. Expression of these mutants may lead to dominant negative inhibition of full-length receptors through formation of inactive hetero-dimers or hetero-oligomers. 

Calix[n]arenes are cyclic condensation products of para-substituted phenol derivatives and formaldehyde [29], They are highly interesting for the development of sensitive coatings due to their conformational flexibility and the ease by which they may be modified chemically. Chemical modification can be done either in the meta position, or by reactions at the hydroxy group. In this way, bulky substituents [30], chelating substituents [31], aromatic residues [32], crown ethers [33,34], peptides [35,36], etc. can be introduced. A first approach to combinatorial synthesis of calix[4]arene receptors has been published by Reinhoudt and co-workers [37,38], who prepared calixarenes with different substituents. In solution, these calixarenes lead to formation of hetero-oligomers with barbiturates, and these hetero-oligomers were detected by MALDI-TOF mass spectrometry and H-NMR spectroscopy. 

Preparation of racemic and optically-active fatty amino acids, their homo- and hetero-oligomers and conjugates, as pharmaceuticals Gibbons, William A. 

The RIS of an hetero-oligomer is that of one of the subunits. The functional unit size will correspond to that of the subunit responsible for the biological activity. However, confusion might occur if the same RIS is obtained by rearranging two or more smaller subunits in a manner to obtain a similar RIS value. In this case a target size analysis of all subunits with a purified system might help distinguish between the possibilities. 

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