Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.3.1.108 (
TAT
)
2,389
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The protein transduction domain (PTD) from the HIV-1 TAT protein has been widely utilized to deliver biologically active macromolecules, including full-length proteins, into a variety of cell types in vitro and in vivo. Without additional targeting signals, the intracellular localization of the proteins delivered in this fashion appears to be cytoplasmic, nuclear or, as recently reported, endosomal. In this study, we show that the presence of the mitochondrial targeting signal (MTS) from hMnSOD on the N-terminus of
TAT
-fusion proteins directs them into mitochondria of breast cancer cells. We generated and purified fusion proteins containing GFP (MTS-GFP-
TAT
) or
Exonuclease III
(MTS-ExoIII-
TAT
) from Escherichia coli. The results of Western blots of subcellular fractions and fluorescent microscopic analyses revealed efficient protein transduction and mitochondrial localization of the fusion proteins. Specific exonuclease activity was found in the mitochondrial extracts isolated from MTS-ExoIII-
TAT
transduced cells. This increased exonuclease activity reduced the repair of mtDNA damage following oxidative stress. This diminished mtDNA repair led to a decrease in survival of breast cancer cells. Thus, the present study demonstrates the applicability of this new approach for intramitochondrial targeting of
TAT
-fusion proteins capable of modulating mitochondrial function and cell survival.
...
PMID:TAT-mediated protein transduction and targeted delivery of fusion proteins into mitochondria of breast cancer cells. 1572 31