Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Peptide Bonds02:43

Peptide Bonds

A peptide bond covalently attaches amino acids through a dehydration reaction. One amino acid's carboxyl group and another amino acid's amino group combine, releasing a water molecule. The resulting bond is the peptide bond. The products that such linkages form are peptides. As more amino acids join this growing chain, the resulting chain is a polypeptide. Each polypeptide has a free amino group at one end. This end has the N-terminal, or the amino-terminal, and the other end has a free...
The Proteasome Structure01:17

The Proteasome Structure

The ubiquitin-proteasome pathway is a well-known mechanism utilized by eukaryotic cells to remove cytoplasmic proteins that are misfolded, damaged, or no longer needed. In this pathway, the protein that needs to be eliminated undergoes a process called ubiquitination, where a chain of ubiquitin molecules is attached to the 48th lysine residue of the target protein. This ubiquitin modification helps the proteasome distinguish between a target protein and a healthy protein.
The proteasome is an...
The Proteasome02:18

The Proteasome

Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
The Proteasome01:13

The Proteasome

Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
Peptide Identification Using Tandem Mass Spectrometry01:33

Peptide Identification Using Tandem Mass Spectrometry

Tandem mass spectrometry, also known as MS/MS or MS2, is an analytical technique that employs two mass analyzers. Essentially it is a series of mass spectrometers that helps isolate a particular biomolecule and then helps study its chemical properties.
This technique helps gather information regarding the protein from which the peptide was obtained and to study the peptides’ amino acid sequence. Identifying peptides from a complex mixture is an important component of the growing field of...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Exploring rifamycin cytotoxic potential through targeted liposomal formulations.

International journal of pharmaceutics·2026
Same author

Targeted degradation of MK2 is insufficient to block inflammatory cytokine production in human cells due to cooperativity with MK3 and MK5.

Frontiers in immunology·2026
Same author

High Shear Wet Granulation Process Common Deficiencies Observed in Recently Submitted New and Abbreviated Drug Applications.

AAPS PharmSciTech·2026
Same author

Discovery of Selective and Orally Bioavailable Heterobifunctional Degraders of Cyclin-Dependent Kinase 2.

Journal of medicinal chemistry·2025
Same author

Hybrid micellar preparations for co-delivery of PARP-1 siRNA and quercetin for cataract treatment.

Journal of controlled release : official journal of the Controlled Release Society·2025
Same author

Therapeutic potential of allosteric HECT E3 ligase inhibition.

Cell·2025

Related Experiment Video

Updated: Jun 21, 2026

Delivery of Proteins, Peptides or Cell-impermeable Small Molecules into Live Cells by Incubation with the Endosomolytic Reagent dfTAT
10:30

Delivery of Proteins, Peptides or Cell-impermeable Small Molecules into Live Cells by Incubation with the Endosomolytic Reagent dfTAT

Published on: September 2, 2015

TAT peptide and its conjugates: proteolytic stability.

Jacob Grunwald1, Tomas Rejtar, Rupa Sawant

  • 1Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts 02115, USA.

Bioconjugate Chemistry
|July 16, 2009
PubMed
Summary
This summary is machine-generated.

Proteolytic cleavage of TATp was significantly reduced by PEGylation and micelle formation. TATp-Mic micelles demonstrated over 100-fold increased stability against proteolysis, enhancing its potential for drug delivery.

More Related Videos

MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent
06:54

MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent

Published on: September 3, 2013

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
11:44

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities

Published on: October 2, 2018

Related Experiment Videos

Last Updated: Jun 21, 2026

Delivery of Proteins, Peptides or Cell-impermeable Small Molecules into Live Cells by Incubation with the Endosomolytic Reagent dfTAT
10:30

Delivery of Proteins, Peptides or Cell-impermeable Small Molecules into Live Cells by Incubation with the Endosomolytic Reagent dfTAT

Published on: September 2, 2015

MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent
06:54

MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent

Published on: September 3, 2013

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
11:44

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities

Published on: October 2, 2018

Area of Science:

  • Bioconjugate Chemistry
  • Drug Delivery Systems
  • Proteomics

Background:

  • The TAT peptide (TATp) is a cell-penetrating moiety used in drug delivery.
  • PEGylation and micelle formation are strategies to improve drug stability and delivery.
  • Understanding the proteolytic stability of TATp conjugates is crucial for their in vivo application.

Purpose of the Study:

  • To investigate the proteolytic cleavage of free TATp, a TATp-PEG(1000)-PE conjugate (TATp-conjugate), and TATp incorporated into mixed micelles (TATp-Mic).
  • To determine the impact of PEGylation and micelle formation on the stability of TATp against proteolytic degradation.
  • To assess the potential of TATp-Mic as a stable cell-penetrating moiety for drug delivery systems.

Main Methods:

  • High-performance liquid chromatography (HPLC) with fluorenylmethyl chloroformate (FMOC) labeling for fluorescent detection.
  • Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) for structural analysis.
  • Kinetic analysis of proteolytic cleavage in human blood plasma and trypsin-containing phosphate-buffered saline (PBS) at pH 7.4.

Main Results:

  • Proteolytic cleavage primarily occurred via endocleavage at the carboxyl terminus, forming an Arg-Arg (RR) dimer.
  • Free TATp exhibited rapid cleavage with a half-life (t(1/2)) of approximately 3.5 minutes.
  • TATp-conjugate showed increased stability with a t(1/2) of approximately 10 minutes (3-fold increase).
  • TATp-Mic demonstrated significant protection against proteolysis, with a t(1/2) exceeding 430 minutes (over 100-fold increase).

Conclusions:

  • PEGylation of TATp increases its proteolytic stability.
  • Incorporation of TATp into PEGylated micelles (TATp-Mic) provides substantial protection against enzymatic degradation.
  • The TATp-Mic formulation is a promising platform for developing stable, cell-penetrating moieties for advanced drug delivery systems.