Hybrid motifs

Hybrid motifs are apparendy unique to fibrillins and LTBPs. They contain primary structural features of both TB motifs towards their N-termini and cbEGF-like domains towards their C-termini. No high-resolution structures have yet been determined for these motifs. Most hybrid motifs contain eight cysteines, but the first hybrid motif of fibril-lin-1 contains nine cysteines one of these cysteines is predicted to be important in forming intermolecular disulphide bonds that stabilize assembled fibrillin-1 (see Section III below Reinhardt et al, 2000b). 

The reaction of a ID organostannoxane coordination polymer (121) with bis(biphenyloxy)bis(4-pyridylo3y) cyclophosphazene (122) afforded molecular (123) and polymeric cyclophosphazene-organostannoxane hybrid motifs (124) (Scheme 16). These compounds have been structurally characterized by NMR and X-ray crystallography. Previous work on the metalation studies of cyclophosphazene ligands has been summarised in two comprehensive review articles. ... 

Vandermeulen GWM, Tziatzios C, Klok HA (2003) Reversible self-organization of poly (ethylene glycol)-based hybrid block copolymers mediated by a de novo four- stranded alpha-helical coiled coil motif Macromolecules 36 4107 114... 

Whereas the mono- and the S/S-dithioether moieties have been used to date, the 1,3-dithianyl motif was used for the first time in 2005 by Ricci et al. as a new hybrid ligand in asymmetric catalysis. Hence, a series of new chiral oxazoline-1,3-dithianes have been successfully applied to the copper-catalysed conjugate addition of ZnEt2 to enones (Scheme 2.16). The expected products were obtained in almost quantitative yields and enantioselectivities of up to 69% ee. 

We have previously shown that a 209 amino acid region (aa288-497, asymmetric localization domain) of Insc is necessary and sufficient for apical cortical localization and for mitotic spindle orientation along the apical-basal axis (Tio et al 1999). In a yeast two-hybrid screen we identified Partner of Inscuteable (Pins), a novel 658aa protein with multiple repeats of the Tetratricopeptide (TPR) motif. Affinity purification experiments using embryonic extracts demonstrate that Pins complexes with Insc in vivo. In vitro protein interaction assays demonstrates that Pins interacts with the Insc asymmetric localization domain (see Yu et al 2000). 

Synthesis of novel polyelectrochromic materials with the new structural motif utilizing stabilized carbocations has been demonstrated by several examples. The Wurster type violene-cyanine hybrid systems (22z+ and 232+) exhibit the presumed two color changes. The new cyanine-cyanine hybrid system (24 ) with a cyanine unit at the one terminus exhibits three color changes. 

Su(var)3-9 in the yeast two-hybrid interaction assay and increase the Su(var)3-9-mediated H3K9 methylation on autosomes and the male X chromosome. Su(var)3-7, contains seven widely spaced zinc-finger motifs, is involved in the recruitment of Su(var)3-9 (Schotta et al, 2002 Delattre et al, 2004). 

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