Cell-surface accumulation of flock house virus-derived peptide leads to efficient internalization via macropinocytosis.

Arginine-rich cell-penetrating peptides (CPPs), including human immunodeficiency virus type 1 (HIV-1) Tat (48-60) and oligoarginines, have been applied as carriers for delivery of cargo molecules, because of their capacity to internalize into cells and penetrate biological membranes. Despite the fact that they have been extensively studied, the factors required for the efficient internalization of CPPs are still unclear. In this report, we evaluated the internalization efficiencies of seven CPPs derived from DNA/RNA-binding peptides, and discovered that a peptide derived from the flock house virus (FHV) coat protein was internalized most efficiently into Chinese hamster ovary (CHO-K1), HeLa, and Jurkat cells.

Novel system to achieve one-pot modification of cargo molecules with oligoarginine vectors for intracellular delivery.

There is a growing number of reports showing the usefulness of cell-penetrating peptides (CPPs) including oligoarginines for intracellular delivery of macromolecules. Although the covalent attachment of the CPP segments to the cargo molecules is usually required to ensure effective delivery, conventional methods of conjugation need several manipulation steps that are often time-consuming and laborious. Here, we report a novel approach to allow easy modification of cargo molecules with oligoarginine CPPs.

Acid wash in determining cellular uptake of Fab/cell-permeating peptide conjugates.

Successful intracellular delivery of various bioactive molecules has been reported using cell-permeating peptides (CPPs) as delivery vectors. To determine the effects of CPPs on the cellular uptake of immunoglobulin Fab fragment, conjugates of a radio-iodinated Fab fragment with CPPs (CPP-(125)I-Fab) derived from HIV-1 TAT, HIV-1 REV, and Antennapedia (ANP) were prepared. These vectors are rich in basic amino acids, and their strong adsorption on cell surfaces often results in overestimation of internalized peptides.

Interaction of arginine-rich peptides with membrane-associated proteoglycans is crucial for induction of actin organization and macropinocytosis.

Arginine-rich peptides, including octaarginine (R8), HIV-1 Tat, and branched-chain arginine-rich peptides, belong to one of the major classes of cell-permeable peptides which deliver various proteins and macromolecules to cells. The importance of the endocytic pathways has recently been demonstrated in the cellular uptake of these peptides. We have previously shown that macropinocytosis is one of the major pathways for cellular uptake and that organization of the F-actin accompanies this process.

Direct and rapid cytosolic delivery using cell-penetrating peptides mediated by pyrenebutyrate.

Intracellular delivery of bioactive molecules using arginine-rich peptides, including oligoarginine and HIV-1 Tat peptides, is a recently developed technology. Here, we report a dramatic change in the methods of internalization for these peptides brought about by the presence of pyrenebutyrate, a counteranion bearing an aromatic hydrophobic moiety. In the absence of pyrenebutyrate, endocytosis plays a major role in cellular uptake.

Arginine carrier peptide bearing Ni(II) chelator to promote cellular uptake of histidine-tagged proteins.

Arginine-rich peptide-mediated protein delivery into living cells is a novel technology for controlling cell functions with therapeutic potential. In this report, a novel approach for the intracellular delivery of histidine-tagged proteins was introduced where a Ni(II) chelate of octaarginine peptide bearing nitrilotriacetic acid [R8-NTA-Ni(II)] was used as a membrane-permeable carrier molecule. Significant internalization of histidine-tagged enhanced green fluorescent protein (EGFP) into HeLa cells was observed by confocal microscopic observation in the presence of R8-NTA-Ni(II).

Interaction of the Escherichia coli lipoprotein NlpI with periplasmic Prc (Tsp) protease.

Escherichia coli spr (suppressor of prc) mutants and nlpI mutants show thermosensitive growth. The thermosensitivity of the spr mutants was suppressed by the nlpI mutations. Expression of the fusion genes encoding hexa-histidine-tagged NlpI (NlpI-His) and purification of the tagged NlpI showed that NlpI-His bound with Prc protease and IbpB chaperone.