N-Methyl-Substituted Fluorescent DAG-Indololactone Isomers Exhibit Dramatic Differences in Membrane Interactions and Biological Activity

• Published in: Chembiochem : a European journal of chemical biology 2011-10, Vol.12 (15), p.2331-2340
• Main Authors: Gal, Noga, Kolusheva, Sofiya, Kedei, Noemi, Telek, Andrea, Naeem, Taiyabah A., Lewin, Nancy E., Lim, Langston, Mannan, Poonam, Garfield, Susan H., El Kazzouli, Saïd, Sigano, Dina M., Marquez, Victor E., Blumberg, Peter M., Jelinek, Raz
• Format: Article
• Language: English
• Subjects: Animals; Cell Membrane - drug effects; Cell Membrane - metabolism; CHO Cells; Cricetinae; diacylglycerol-lactones; Diglycerides - chemistry; Diglycerides - pharmacology; FRET; Guanine Nucleotide Exchange Factors - metabolism; Humans; Indoles - chemistry; Indoles - pharmacokinetics; Indoles - pharmacology; Isomerism; kinases; Lactones - chemistry; Lactones - pharmacokinetics; Lactones - pharmacology; phorbol esters; Protein Isoforms - antagonists & inhibitors; Protein Isoforms - metabolism; Protein Kinase C - antagonists & inhibitors; Protein Kinase C - metabolism; Protein Kinase C-alpha - antagonists & inhibitors; Protein Kinase C-alpha - metabolism; Protein Kinase Inhibitors - chemistry; Protein Kinase Inhibitors - pharmacokinetics; Protein Kinase Inhibitors - pharmacology; Protein Transport - drug effects; vesicles
• ISSN: 1439-4227; 1439-7633
• DOI: 10.1002/cbic.201100246

N‐methyl‐substituted diacylglycerol–indololactones (DAG–indololactones) are newly synthesized effectors of protein kinase C (PKC) isoforms and exhibit substantial selectivity between RasGRP3 and PKCα. We present a comprehensive analysis of membrane interactions and biological activities of several DAG–indololactones. Translocation and binding activity assays underline significant variations between the PKC translocation characteristics affected by the ligands as compared to their binding activities. In parallel, the fluorescent properties of the ligands were employed for analysis of their membrane association profiles. Specifically, we found that a slight change in the linkage to the indole ring resulted in significant differences in membrane binding and association of the DAG–indololactones with lipid bilayers. Our analysis shows that seemingly small structural modifications of the hydrophobic regions of these biomimetic PKC effectors contribute to pronounced modulation of membrane interactions of the ligands. Bound up: We have analyzed the membrane interactions and biological activities of several diacylglycerol–indololactones (DAG–indololactones). The positional isomers of the tested compounds were found to exhibit pronounced differences in their PKC translocation activities and their interactions with lipid bilayers (see figure).