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Updated: Aug 8, 2026

Measurement of Vacuolar and Cytosolic pH In Vivo in Yeast Cell Suspensions
Published on: April 19, 2013
Changes in Intracellular pH Are Not Correlated with the Circadian Rhythm of Neurospora
1Biological Laboratories, Harvard University, Cambridge, Massachusetts 02138.
Abstract:
Intracellular pH (pH(i)) was measured during the circadian cycle of Neurospora. Internal pH of Neurospora cultures in liquid medium was assayed by the 5,5-dimethyl-2,4-oxazolidinedione method and gave values for pH(i) which were similar to those previously obtained by other workers using pH-microelectrodes with agar-grown cultures. Cytoplasmic pH changed in liquid medium cultures, but these changes were not related to the circadian clock. Furthermore, treatments which raise or lower pH(i) do not phase-shift the circadian rhythm. These results indicate that pH(i) plays no specific role in regulating the circadian clock of Neurospora.
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