SERS nanosensors that report pH of endocytic compartments during FcεRI transit

Nowak-Lovato, K. L.; Wilson, Bridget S.; Rector, Kirk D.
November 2010
Analytical & Bioanalytical Chemistry;Nov2010, Vol. 398 Issue 5, p2019
Academic Journal
Recently, the development of an IgE receptor (FcεRI)-targeted, pH-sensitive, surface-enhanced Raman spectroscopy (SERS) nanosensor has been demonstrated by Nowak-Lovato and Rector (Appl Spectrosc 63:387-395, ). The targeted nanosensor enables spatial and temporal pH measurements as internalized receptors progress through endosomal compartments in live cells. Trafficking of receptor-bound nanosensors was compared at physiological temperature (37 °C) versus room temperature (25 °C). As expected, we observed markedly slower progression of receptors through low-pH endocytic compartments at the lower temperature. We also demonstrate the utility of the nanosensors to measure directly changes in the pH of intracellular compartments after treatment with bafilomycin or amiloride. We report an increase in endosome compartment pH after treatment with bafilomycin, an H ATPase pump inhibitor. Decreased endosomal luminal pH was measured in cells treated with amiloride, an inhibitor of Na/H exchange. The decrease in amiloride-treated cells was transient, followed by a recovery period of approximately 15-20 min to restore endosomal pH. These experiments demonstrate the novel application of Raman spectroscopy to monitor local pH environment in live cells with the use of targeted SERS nanosensors. [Figure not available: see fulltext.]


Related Articles

  • Organelle-specific, rapid induction of molecular activities and membrane tethering. Komatsu, Toru; Kukelyansky, Igor; McCaffery, J. Michael; Ueno, Tasuku; Varela, Lidenys C.; Inoue, Takanari // Nature Methods;Mar2010, Vol. 7 Issue 3, p206 

    Using new chemically inducible dimerization probes, we generated a system to rapidly target proteins to individual intracellular organelles. Using this system, we activated Ras GTPase at distinct intracellular locations and induced tethering of membranes from two organelles, endoplasmic...

  • Selective involvement of BH3-only proteins and differential targets of Noxa in diverse apoptotic pathways. Zhang, L.; Lopez, H.; George, N. M.; Liu, X.; Pang, X.; Luo, X. // Cell Death & Differentiation;May2011, Vol. 18 Issue 5, p864 

    The BH3-only proteins of the Bcl-2 family are known to mediate mitochondrial dysfunction during apoptosis. However, the identity of the critical BH3-only proteins and the mechanism of their action following treatment by diverse apoptotic stimuli remain to be fully resolved. We therefore used...

  • Origin and evolution of the peroxisomal proteome. Gabaldón, Toni; Snel, Berend; Van Zimmeren, Frank; Hemrika, Wieger; Tabak, Henk; Huynen, Martijn A. // Biology Direct;2006, Vol. 1, p8 

    Background: Peroxisomes are ubiquitous eukaryotic organelles involved in various oxidative reactions. Their enzymatic content varies between species, but the presence of common protein import and organelle biogenesis systems support a single evolutionary origin. The precise scenario for this...

  • Probabilistic density maps to study global endomembrane organization. Schauer, Kristine; Duong, Tarn; Bleakley, Kevin; Bardin, Sabine; Bornens, Michel; Goud, Bruno // Nature Methods;Jul2010, Vol. 7 Issue 7, p560 

    We developed a computational imaging approach that describes the three-dimensional spatial organization of endomembranes from micromanipulation-normalized mammalian cells with probabilistic density maps. Applied to several well-known marker proteins, this approach revealed the average...

  • Silencing by small RNAs is linked to endosomal trafficking. Lee, Young Sik; Pressman, Sigal; Andress, Arlise P.; Kim, Kevin; White, Jamie L.; Cassidy, Justin J.; Xin Li; Lubell, Kim; Do Hwan Lim; Ik Sang Cho; Nakahara, Kenji; Preall, Jonathan B.; Bellare, Priya; Sontheimer, Erik J.; Carthew, Richard W. // Nature Cell Biology;Sep2009, Vol. 11 Issue 9, p1150 

    Small RNAs direct RNA-induced silencing complexes (RISCs) to regulate stability and translation of mRNAs. RISCs associated with target mRNAs often accumulate in discrete cytoplasmic foci known as GW-bodies. However, RISC proteins can associate with membrane compartments such as the Golgi and...

  • Endosome-mitochondria juxtaposition during apoptosis induced by H. pylori VacA. Calore, F.; Genisset, C.; Casellato, A.; Rossato, M.; Codolo, G.; Esposti, M. D.; Scorrano, L.; de Bernard, M. // Cell Death & Differentiation;Nov2010, Vol. 17 Issue 11, p1707 

    The vacuolating cytotoxin (VacA) is an important virulence factor of Helicobacter pylori with pleiotropic effects on mammalian cells, including the ability to trigger mitochondria-dependent apoptosis. However, the mechanism by which VacA exerts its apoptotic function is unclear. Using a genetic...

  • Structural features within the nascent chain regulate alternative targeting of secretory proteins to mitochondria. Pfeiffer, Natalie V; Dirndorfer, Daniela; Lang, Sven; Resenberger, Ulrike K; Restelli, Lisa M; Hemion, Charles; Miesbauer, Margit; Frank, Stephan; Neutzner, Albert; Zimmermann, Richard; Winklhofer, Konstanze F; Tatzelt, Jörg // EMBO Journal;4/3/2013, Vol. 32 Issue 7, p1036 

    Protein targeting to specified cellular compartments is essential to maintain cell function and homeostasis. In eukaryotic cells, two major pathways rely on N-terminal signal peptides to target proteins to either the endoplasmic reticulum (ER) or mitochondria. In this study, we show that the ER...

  • Intracellular transport and localization of microsomal cytochrome P450. Neve, Etienne P. A.; Ingelman-Sundberg, Magnus // Analytical & Bioanalytical Chemistry;Nov2008, Vol. 392 Issue 6, p1075 

    The cytochrome P450 (P450) enzymes are mainly localized to the endoplasmic reticulum (ER), where they function within catalytic complexes metabolizing xenobiotics and some endogenous substrates. However, certain members of families 1–3 were also found in other subcellular compartments,...

  • Death receptor ligation triggers membrane scrambling between Golgi and mitochondria. Ouasti, S.; Matarrese, P.; Paddon, R.; Khosravi-Far, R.; Sorice, M.; Tinari, A.; Malorni, W.; Degli Esposti, M. // Cell Death & Differentiation;Mar2007, Vol. 14 Issue 3, p453 

    Subcellular organelles such as mitochondria, endoplasmic reticulum (ER) and the Golgi complex are involved in the progression of the cell death programme. We report here that soon after ligation of Fas (CD95/Apo1) in type II cells, elements of the Golgi complex intermix with mitochondria. This...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics