Lifetime-based pH sensors: indicators for acidic environments.
AuthorsLin HJ, Szmacinski H, Lakowicz JR
JournalAnal Biochem
PubMed ID10094788
'We characterized the pH-dependent intensity decays of three fluorophores, Oregon green 514 carboxylic acid, Cl-NERF, and DM-NERF, using frequency-domain fluorometry, with the objective of identifying lifetime-based sensors for low pH values. These three probes were originally designed as dual excitation wavelength-ratiometric probes, with high photostability and high quantum yields in ... More
Changes in yolk platelet pH during Xenopus laevis development correlate with yolk utilization. A quantitative confocal microscopy study.
AuthorsFagotto F, Maxfield FR
JournalJ Cell Sci
PubMed ID7706389
'The variations of the pH in Xenopus yolk platelets have been estimated by fluorescence confocal microscopy and computer image processing. For pH measurements in vitellogenic oocytes, the pH-sensitive fluorescent dye, DM-NERF, was coupled to vitellogenin, and the DM-NERF-vitellogenin was taken up by oocytes via receptor-mediated endocytosis. Dual emission ratio measurements ... More
Elicitor-activated phospholipase A(2) generates lysophosphatidylcholines that mobilize the vacuolar H(+) pool for pH signaling via the activation of Na(+)-dependent proton fluxes.
AuthorsViehweger K, Dordschbal B, Roos W
JournalPlant Cell
PubMed ID12119371
The elicitation of phytoalexin biosynthesis in cultured cells of California poppy involves a shift of cytoplasmic pH via the transient efflux of vacuolar protons. Intracellular effectors of vacuolar proton transport were identified by a novel in situ approach based on the selective permeabilization of the plasma membrane for molecules of ... More
ATP regulates the differentiation of mammalian skeletal muscle by activation of a P2X5 receptor on satellite cells.
AuthorsRyten M, Dunn PM, Neary JT, Burnstock G
JournalJ Cell Biol
PubMed ID12135987
ATP is well known for its role as an intracellular energy source. However, there is increasing awareness of its role as an extracellular messenger molecule (Burnstock, 1997). Although evidence for the presence of receptors for extracellular ATP on skeletal myoblasts was first published in 1983 (Kolb and Wakelam), their physiological ... More
Fluorescence lifetime-resolved pH imaging of living cells.
AuthorsLin HJ, Herman P, Lakowicz JR
JournalCytometry A
PubMed ID12655651
BACKGROUND: The regulation and maintenance of intracellular pH are critical to diverse metabolic functions of the living cells. Fluorescence time-resolved techniques and instrumentations have advanced rapidly and enabled the imaging of intracellular pH based on the fluorescence lifetimes. METHODS: The frequency-domain fluorescence lifetime imaging microscopy (FLIM) and fluorophores displaying appropriate ... More
Fluorescent rhodol derivatives: versatile, photostable labels and tracers.
AuthorsWhitaker JE, Haugland RP, Ryan D, Hewitt PC, Haugland RP, Prendergast FG
JournalAnal Biochem
PubMed ID1481981
A series of chemically reactive, fluorescent rhodol derivatives was prepared and evaluated. Reactive functional groups included activated esters, amines, haloacetamides, fixable hydrazide derivatives, acrylamides, and photoaffinity reagents. Depending on the choice of substituents, absorption maxima of the dyes varied from 490 to 550 nm with extinction coefficients that were generally ... More