Reversible photocontrol of DNA coacervation

Reversible photocontrol of DNA binding by a designed GCN4-bZIP protein.

Synthetic photocontrolled proteins could be powerful tools for probing cellular chemistry. Several previous attempts to produce such systems by incorporating photoisomerizable chromophores into biomolecules have led to photocontrol but with incomplete reversibility, where the chromophore becomes trapped in one photoisomeric state. We report here the design of a modified GCN4-bZIP DNA-binding pr...

Photocontrol of reversible amyloid formation with a minimal-design peptide.

Amyloid aggregates are highly ordered fibrillar assemblies of polypeptides involved in a number of neurodegenerative diseases. Very little is known on the pathways of self-assembly of peptides into the final amyloid fibrils, which is due in part to the difficulty of triggering the aggregation process in a controlled manner. Here we present the design and validation of a cross-linked hexapeptide...

Photocontrol of DNA duplex formation by using azobenzene-bearing oligonucleotides.

The duplex-forming activities of oligonucleotides can be photomodulated by incorporation of an azobenzene unit. Upon isomerizing the trans-azobenzene to the cis form by irradiation with UV light, the T(m) value of the duplex (with the complementary DNA) is lowered so that the duplex is dissociated. The duplex is formed again when the cis-azobenzene is converted to the trans-azobenzene by irradi...

Reversible photocontrol of biological systems by the incorporation of molecular photoswitches.

Photocontrol of Smectic Spacing

We report on the results of optical, X-ray and NMR studies of light-induced phenomena in smectic phases triggered by molecular phototransformations. UV irrddiation causes trans-to-cis isomerization of the dopant molecules while irradiation in thc visible part of the spectrum facilitates cis-to-trans lelaxation. Cis-to-trans isomerization decrcaws the smectic layers' spacing; as the result. a sm...