This review is about intracellular pH sensors, includingsmall fluorescent organic molecules, nanoparticles, andfluorescent proteins, e.g., GFP. It focuses on their preparations, photophysical properties, and advantages/disadvantagesfor intracellular pH measurements. The discussion is limitedto fluorescent indicators that have been applied to measureintracellular pH values since 1980. ... More
Synthesis and photophysical properties of new fluorinated benzo[c]xanthene dyes as intracellular pH indicators.
AuthorsLiu J, Diwu Z, Leung WY
JournalBioorg Med Chem Lett
PubMed ID11677123
Two new fluorinated benzo[c]xanthene dyes were synthesized by reaction of fluorinated 1,6-dihydroxynaphthalenes with 2,4- (and 2,5)-dicarboxy-3'-dimethylamino-2'-hydroxybenzophenone. The two critical fluorinated 1,6-dihydroxynaphthalene intermediates were prepared via a regioselective route. The fluorinated benzo[c]xanthene dyes exhibit desired lower pK(a) values (6.4 and 7.2, respectively) than their parent compound (pK(a)=7.5) while the pH-dependent dual-emission ... More
Tissue-specific regulation of sodium/proton exchanger isoform 3 activity in Na(+)/H(+) exchanger regulatory factor 1 (NHERF1) null mice. cAMP inhibition is differentially dependent on NHERF1 and exchange protein directly activated by cAMP in ileum versus proximal tubule.
AuthorsMurtazina R, Kovbasnjuk O, Zachos NC, Li X, Chen Y, Hubbard A, Hogema BM, Steplock D, Seidler U, Hoque KM, Tse CM, De Jonge HR, Weinman EJ, Donowitz M,
JournalJ Biol Chem
PubMed ID17580307
The multi-PDZ domain containing protein Na(+)/H(+) Exchanger Regulatory Factor 1 (NHERF1) binds to Na(+)/H(+) exchanger 3 (NHE3) and is associated with the brush border (BB) membrane of murine kidney and small intestine. Although studies in BB isolated from kidney cortex of wild type and NHERF1(-/-) mice have shown that NHERF1 ... More
Intracellular pH distribution in Saccharomyces cerevisiae cell populations, analyzed by flow cytometry.
AuthorsValli M, Sauer M, Branduardi P, Borth N, Porro D, Mattanovich D
JournalAppl Environ Microbiol
PubMed ID15746355
Intracellular pH has an important role in the maintenance of the normal functions of yeast cells. The ability of the cell to maintain this pH homeostasis also in response to environmental changes has gained more and more interest in both basic and applied research. In this study we describe a ... More
pH-Dependence of extrinsic and intrinsic H(+)-ion mobility in the rat ventricular myocyte, investigated using flash photolysis of a caged-H(+) compound.
AuthorsSwietach P, Spitzer KW, Vaughan-Jones RD
JournalBiophys J
PubMed ID17056723
Passive H(+)-ion mobility within eukaryotic cells is low, due to H(+)-ion binding to cytoplasmic buffers. A localized intracellular acidosis can therefore persist for seconds or even minutes. Because H(+)-ions modulate so many biological processes, spatial intracellular pH (pH(i))-regulation becomes important for coordinating cellular activity. We have investigated spatial pH(i)-regulation in ... More
Coverslip hypoxia: a novel method for studying cardiac myocyte hypoxia and ischemia in vitro.
AuthorsPitts KR, Toombs CF
JournalAm J Physiol Heart Circ Physiol
PubMed ID15155258
In vitro experimental models designed to study the effects of hypoxia and ischemia typically employ oxygen-depleted media and/or hypoxic chambers. These approaches, however, allow for metabolites to diffuse away into a large volume and may not replicate the high local concentrations that occur in ischemic myocardium in vivo. We describe ... More