Publications by Keitaro Umezawa

Fluorogenic Probes for Multicolor Imaging in Living Cells

Kai Johnsson, Luc Reymond, Grazvydas Lukinavicius, Olivier Vincent Sallin, Keitaro Umezawa

Here we present a far-red, silicon-rhodamine-based fluorophore (SiR700) for live-cell multicolor imaging. SiR700 has excitation and emission maxima at 690 nm and 715 nm, respectively. SiR700-based probes for F-actin, microtubules, lysosomes and SNAP-tag ar ...

American Chemical Society2016

Cell permeable, fluorescent dye

Kai Johnsson, Grazvydas Lukinavicius, Keitaro Umezawa

The invention pertains to a near-infrared fluorescent dye that is cell permeable and can be attached to selected proteins in living cells. The dye has the general formula (I) or its or its corresponding spirolactone (II) wherein Y is chosen from the group ...

2013

Selective Chemical Crosslinking Reveals a Cep57-Cep63-Cep152 Centrosomal Complex

Kai Johnsson, Pierre Gönczy, Luc Reymond, Grazvydas Lukinavicius, Keitaro Umezawa

The centrosome functions as the main microtubule-organizing center of animal cells and is crucial for several fundamental cellular processes [1]. Abnormalities in centrosome number and composition correlate with tumor progression [2, 3] and other diseases ...

Elsevier2013

A Fluorescent Sensor for GABA and Synthetic GABA(B) Receptor Ligands

Kai Johnsson, Luc Reymond, Anastasiya Masharina, Keitaro Umezawa

While gamma-aminobutyric acid (GABA) is the main inhibitory neurotransmitter, suitable tools to measure its concentration in living cells with high spatiotemporal resolution are missing. Herein, we describe the first ratiometric fluorescent sensor for GABA ...

American Chemical Society2012

Visualizing Biochemical Activities in Living Cells through Chemistry

Kai Johnsson, Luc Reymond, Rudolf Griss, Alberto Schena, Grazvydas Lukinavicius, Karolina Bojkowska, Birgit Mollwitz, Matthias Albert Brun, Keitaro Umezawa, Anastasiya Masharina

The development of molecular probes to visualize cellular processes is an important challenge in chemical biology. One possibility to create such cellular indicators is based on the selective labeling of proteins with synthetic probes in living cells. Over ...

2011