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Full-Text Articles in Life Sciences
Identification Of A Short Cell-Penetrating Peptide From Bovine Lactoferricin For Intracellular Delivery Of Dna In Human A549 Cells, Betty Revon Liu, Yue-Wern Huang, Robert Aronstam, Han-Jung Lee
Identification Of A Short Cell-Penetrating Peptide From Bovine Lactoferricin For Intracellular Delivery Of Dna In Human A549 Cells, Betty Revon Liu, Yue-Wern Huang, Robert Aronstam, Han-Jung Lee
Biological Sciences Faculty Research & Creative Works
Cell-penetrating peptides (CPPs) have been shown to deliver cargos, including protein, DNA, RNA, and nanomaterials, in fully active forms into live cells. Most of the CPP sequences in use today are based on non-native proteins that may be immunogenic. Here we demonstrate that the L5a CPP (RRWQW) from bovine lactoferricin (LFcin), stably and noncovalently complexed with plasmid DNA and prepared at an optimal nitrogen/phosphate ratio of 12, is able to efficiently enter into human lung cancer A549 cells. The L5a CPP delivered a plasmid containing the enhanced green fluorescent protein (EGFP) coding sequence that was subsequently expressed in …
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
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
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 …
Nona-Arginine Facilitates Delivery Of Quantum Dots Into Cells Via Multiple Pathways, Yi Xu, Betty Revon Liu, Han Jung Lee, Katie Shannon, Jeffrey G. Winiarz, Tien-Chun Wang, Huey-Jenn Chiang, Yue-Wern Huang
Nona-Arginine Facilitates Delivery Of Quantum Dots Into Cells Via Multiple Pathways, Yi Xu, Betty Revon Liu, Han Jung Lee, Katie Shannon, Jeffrey G. Winiarz, Tien-Chun Wang, Huey-Jenn Chiang, Yue-Wern Huang
Biological Sciences Faculty Research & Creative Works
Semiconductor quantum dots (QDs) have recently been used to deliver and monitor biomolecules, such as drugs and proteins. However, QDs alone have a low efficiency of transport across the plasma membrane. In order to increase the efficiency, we used synthetic nona-arginine (SR9), a cell-penetrating peptide, to facilitate uptake. We found that SR9 increased the cellular uptake of QDs in a noncovalent binding manner between QDs and SR9. Further, we investigated mechanisms of QD/SR9 cellular internalization. Low temperature and metabolic inhibitors markedly inhibited the uptake of QD/SR9, indicating that internalization is an energy-dependent process. Results from both the pathway inhibitors and …
Mad2 And Bubr1 Function In A Single Checkpoint Pathway That Responds To A Loss Of Tension, Katie Shannon, Julie C. Canman, Edward D. Salmon
Mad2 And Bubr1 Function In A Single Checkpoint Pathway That Responds To A Loss Of Tension, Katie Shannon, Julie C. Canman, Edward D. Salmon
Biological Sciences Faculty Research & Creative Works
The spindle checkpoint monitors microtubule attachment and tension at kinetochores to ensure proper chromosome segregation. Previously, PtK1 cells in hypothermic conditions (23°C) were shown to have a pronounced mitotic delay, despite having normal numbers of kinetochore microtubules. At 23°C, we found that PtK1 cells remained in metaphase for an average of 101 min, compared with 21 min for cells at 37°C. The metaphase delay at 23°C was abrogated by injection of Mad2 inhibitors, showing that Mad2 and the spindle checkpoint were responsible for the prolonged metaphase. Live cell imaging showed that kinetochore Mad2 became undetectable soon after chromosome congression. Measurements …
Anaphase Onset Does Not Require The Microtubule-Dependent Depletion Of Kinetochore And Centromere-Binding Proteins, Julie C. Canman, Nitin Sharma, Aaron F. Straight, Katie Shannon, Guowei Fang, Edward D. Salmon
Anaphase Onset Does Not Require The Microtubule-Dependent Depletion Of Kinetochore And Centromere-Binding Proteins, Julie C. Canman, Nitin Sharma, Aaron F. Straight, Katie Shannon, Guowei Fang, Edward D. Salmon
Biological Sciences Faculty Research & Creative Works
Spindle checkpoint proteins, such as Mad2 and BubR1, and the motors dynein/dynactin and CENP-E usually leave kinetochores prior to anaphase onset by microtubule-dependent mechanisms. Likewise, 'chromosome passenger proteins' including INCENP are depleted from the centromeres after anaphase onset and then move to the midzone complex, an event that is essential for cytokinesis. Here we test whether the cell cycle changes that occur at anaphase onset require or contribute to the depletion of kinetochore and centromere proteins independent of microtubules. This required the development of a novel non-antibody method to induce precocious anaphase onset in vivo by using a bacterially expressed …
Mutations In Two Ku Homologs Define A Dna End-Joining Repair Pathway In Saccharomyces Cerevisiae, George Todd Milne, Shengfang Jin, Katie Shannon, David T. Weaver
Mutations In Two Ku Homologs Define A Dna End-Joining Repair Pathway In Saccharomyces Cerevisiae, George Todd Milne, Shengfang Jin, Katie Shannon, David T. Weaver
Biological Sciences Faculty Research & Creative Works
DNA double-strand break (DSB) repair in mammalian cells is dependent on the Ku DNA binding protein complex. However, the mechanism of Ku-mediated repair is not understood. We discovered a Saccharomyces cerevisiae gene (KU80) that is structurally similar to the 80-kDa mammalian Ku subunit. Ku80 associates with the product of the HDF1 gene, forming the major DNA end-binding complex of yeast cells. DNA end binding was absent in ku80Δ, hdf1Δ, or ku80Δ hdf1Δ strains. Antisera specific for epitope tags on Ku80 and Hdf1 were used in supershift and immunodepletion experiments to show that both proteins …