1: Biochem Int  1992 Apr;26(5):943-51 

Photomodulation of the nucleating activity of a photocleavable crosslinked actin
dimer.

Marriott G, Miyata H, Kinosita K Jr.

Department of Physics, Faculty of Science and Technology, Keio University,
Yokohama, Japan.

The ability to generate substrate concentration jumps through photo-deprotection
of amine, carboxyl and phosphate groups has been an important development for
investigations of protein activity in complex systems. To broaden the
versatility and applications of photo-deprotection techniques for the
photomodulation of protein activity we describe the synthesis and
characterisation of a reagent for generating free thiol from thioether groups
and a related photocleavable, heterobifunctional crosslinking reagent. Chemical
and spectroscopic studies of a model thiol protected derivative were used to
show some features of thiol group photodeprotection. To demonstrate how the
photocleavable crosslinking reagent may be used to modulate the activity of
proteins we investigated the effect of light on the nucleating activity of
crosslinked actin dimer; thus following near-ultraviolet irradiation of the
actin dimer the crosslink was cleaved, presumeably at the thioether bond,
resulting in the concomitant dissociation of dimer, loss of nucleating activity
and creation of a concentration jump of polymerisable G-actin monomer. On the
basis of this initial study we discuss applications and limitations of these
reagents for the photomodulation of protein activity in vitro and in vivo.

PMID: 1610392 [PubMed - indexed for MEDLINE]