Life Sciences Commons^™

Endocytic Trafficking Of Nanoparticles Delivered By Cell-Penetrating Peptides Comprised Of Nona-Arginine And A Penetration Accelerating Sequence, Betty Revon Liu, Shih-Yen Lo, Chia-Chin Liu, Chia-Lin Chyan, Yue-Wern Huang, Robert Aronstam, Han-Jung Lee

Biological Sciences Faculty Research & Creative Works

Cell-penetrating peptides (CPPs) can traverse cellular membranes and deliver biologically active molecules into cells. In this study, we demonstrate that CPPs comprised of nona-arginine (R9) and a penetration accelerating peptide sequence (Pas) that facilitates escape from endocytic lysosomes, denoted as PR9, greatly enhance the delivery of noncovalently associated quantum dots (QDs) into human A549 cells. Mechanistic studies, intracellular trafficking analysis and a functional gene assay reveal that endocytosis is the main route for intracellular delivery of PR9/QD complexes. Endocytic trafficking of PR9/QD complexes was monitored using both confocal and transmission electron microscopy (TEM). Zeta-potential and size analyses indicate the importance …

Intracellular Delivery Of Nanoparticles And Dnas By Ir9 Cell-Penetrating Peptides, Betty Revon Liu, Ji-Sing Liou, Yue-Wern Huang, Robert Aronstam, Han-Jung Lee

Biological Sciences Faculty Research & Creative Works

Cell-penetrating peptides (CPPs) comprised of basic amino residues are able to cross cytoplasmic membranes and are able to deliver biologically active molecules inside cells. However, CPP/cargo entrapment in endosome limits biomedical utility as cargoes are destroyed in the acidic environment. In this study, we demonstrate protein transduction of a novel CPP comprised of an INF7 fusion peptide and nona-arginine (designated IR9). IR9 noncovalently interacts with quantum dots (QDs) and DNAs to form stable IR9/QD and IR9/DNA complexes which are capable of entering human A549 cells. Zeta-potentials were a better predictor of transduction efficiency than gel shift analysis, emphasizing the importance …

Mechanistic Studies Of Intracellular Delivery Of Proteins By Cell-Penetrating Peptides In Cyanobacteria, Betty Revon Liu, Yue-Wern Huang, Han-Jung Lee

Biological Sciences Faculty Research & Creative Works

Background: The plasma membrane plays an essential role in selective permeability, compartmentalization, osmotic balance, and cellular uptake. The characteristics and functions of cyanobacterial membranes have been extensively investigated in recent years. Cell-penetrating peptides (CPPs) are special nanocarriers that can overcome the plasma membrane barrier and enter cells directly, either alone or with associated cargoes. However, the cellular entry mechanisms of CPPs in cyanobacteria have not been studied.

Results: In the present study, we determine CPP-mediated transduction efficiency and internalization mechanisms in cyanobacteria using a combination of biological and biophysical methods. We demonstrate that both Synechocystis sp. PCC 6803 and Synechococcus …