Transient Interaction

Protein-protein interactions between heterodimeric protein pairs that form only transient interactions can be detected, y-secre-tase is presenilin-1 (PS1) dependent [51-53]. PS1 is a 467-amino acid, 9-transmembrane domain protein. Over 100 documented single point mutations are known to cause autosomal-dominant familial AD (FAD) [54], in which the ratio of the more fibrilogenic variety of A ft (A/142) to the less fibrilogenic variety (A/140) is increased. Chinese hamster ovary (CHO) cells were stably transfected with human APP and either wild type or mutant PS1 [4, 55]. 

In the absence of aging (deactivation) of the catalyst, a phenomenological definition of catalysis would be enhancement of chemical reactions or a change of their rate under the influence of substances — catalysts — which several times enter into transient chemical interactions with reaction participants and then, after each cycle of transient interactions, regenerate their chemical identity [1]. 

The discovery of self-focussing of intense laser beams 318 ) and the phenomena of self-induced transparency 318b) have stimulated a whole new class of experimental investigations which give information about the transient interaction between light and matter 318c)... 

The contractile force of muscle is generated by the interaction of two proteins, myosin and actin. These proteins are arranged in filaments that undergo transient interactions and slide past each other to bring about contraction. Together, actin and myosin make up more than 80% of the protein mass of muscle. 

The signaling process appears to involve a series of molecular ON and OFF switches that are driven by binding interactions between components of the ternary complex, guanine nucleotides, and effectors (Vetter and Wittinghofer, 2001). In cells, the transient interaction of a ligand-activated receptor with a heterotrimeric G protein causes the rapid ejection of an otherwise stably bound GDP nucleotide from the nucleotide-binding... 

Other Transient Interactions. The PVA/borax example dealt with the effects of surface exposure of a two-component polymer system to a wetting liquid. We discovered a practical example of this class of phenomena in a plasticized poly (vinyl chloride) (PVC) system. A peculiar plasticizer (tetraethyl methylene bisphosphonate) for PVC has been found (6) which has the unusual property of exuding out of PVC immediately upon exposure to high humidity. The plasticizer quickly re-enters the resin when the humidity is reduced. A film of 60% resin and 40% plasticizer was solvent cast from tetrahydrofuran onto an impedometer bar and was subjected to sudden high humidity exposure. 

Mizzen, L. A., Kabiling, A. N., and Welch, W. J. (1991). The two mammalian mitochondrial stress proteins, grp 75 and hsp 58, transiently interact with newly synthesized mitochondrial proteins. Cell Regal. 2, 165—179. 

Y2H screening is probably more sensitive for detecting transient interactions whereas TAP-TAG is more efficient at detecting connections between proteins in stable complexes although the washing step during the elution process may fail to identify complexes which components are linked by weak interactions. On one hand Y2H gives comprehensive data on binary interactions, on the other hand TAP-TAG... 

Seraphin, B. (2002) Identification of transiently interacting proteins and of stable protein complexes. In Advances in Protein Chemistry. J. Janin and S.J. Wodak, eds. (U S A. Elsevier Science), vol. 61, pp. 99-117. 

Seraphin, B. 2002. Identification of transiently interacting proteins and of stable protein complexes. Adv Protein Chem 61 99-117. 

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