Root Hair Electrophysiology

Lew, Roger R.

doi:10.1007/978-3-540-79405-9_9

Cited by 3 publications

(1 citation statement)

References 91 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Under these conditions

J_{{normalH}^{+},eff}^{net}

has to be adjusted by feedback control to regulate the P‐type ATPase and/or the cotransporters which catalyze a backflow of H + across the plasma membrane. There are controversial concepts and reports in the literature concerning the regulation of H + ‐ATPase by its substrate, and by the pmf: while some authors consider the pump to be an ideal current source which is independent of the pmf over a wide range (Lew, 2009), others found a strong increase in the pump activity with the apoplastic pH, and with a decrease in the pH gradient across the membrane (e.g. Zhu et al ., 2007).…”

Section: The Biophysical Ph Clampmentioning

confidence: 99%

Biochemical and biophysical pH clamp controlling Net H⁺ efflux across the plasma membrane of plant cells

Wegner

Zhang

et al. 2021

New Phytologist

View full text Add to dashboard Cite

Summary P‐type H+ ATPases mediate active H+ efflux from plant cells. They generate a proton motive force across the plasma membrane, providing the free energy to drive the transport of other solutes, partly by coupling to H+ influx. Wegner & Shabala (2020) recently suggested that passive H+ influx can exceed pump‐driven efflux due to ‘active buffering’, that is, cytosolic H+ scavenging and apoplastic H+ generation by metabolism (‘biochemical pH clamp’). Charge balance is provided by K+ efflux or anion influx. Here, this hypothesis is extended to net H+ efflux: even though H+ pumping is faster than backflow via symporters and antiporters, a progressive increase in the transmembrane pH gradient is avoided. Cytosolic H+ release is associated with bicarbonate formation from CO2. Bicarbonate serves as substrate for the PEPCase, catalyzing the reaction from phosphoenolpyruvate to oxaloacetate, which is subsequently reduced to malate. Organic anions such as malate and citrate are released across the plasma membrane and are (partly) protonated in the apoplast, thus limiting pump‐induced acidification. Moreover, a ‘biophysical pH clamp’ is introduced, that is, adjustment of apoplastic/cytosolic pH involving net H+ fluxes across the plasma membrane, while the gradient between compartments is maintained. The clamps are not mutually exclusive but are likely to coexist.

show abstract

“…Under these conditions

J_{{normalH}^{+},eff}^{net}

Section: The Biophysical Ph Clampmentioning

confidence: 99%

Biochemical and biophysical pH clamp controlling Net H⁺ efflux across the plasma membrane of plant cells

Wegner

Zhang

et al. 2021

New Phytologist

View full text Add to dashboard Cite

show abstract

Electrotonic potentials in Aloe vera L.: Effects of intercellular and external electrodes arrangement

Volkov

Nyasani

Tuckett

et al. 2017

Bioelectrochemistry

View full text Add to dashboard Cite

Electrical signal propagation within and between tomato plants

Volkov

Shtessel

2018

Bioelectrochemistry

View full text Add to dashboard Cite

Root Hair Electrophysiology

Cited by 3 publications

References 91 publications

Biochemical and biophysical pH clamp controlling Net H⁺ efflux across the plasma membrane of plant cells

Biochemical and biophysical pH clamp controlling Net H⁺ efflux across the plasma membrane of plant cells

Electrotonic potentials in Aloe vera L.: Effects of intercellular and external electrodes arrangement

Electrical signal propagation within and between tomato plants

Contact Info

Product

Resources

About

Root Hair Electrophysiology

Cited by 3 publications

References 91 publications

Biochemical and biophysical pH clamp controlling Net H+ efflux across the plasma membrane of plant cells

Biochemical and biophysical pH clamp controlling Net H+ efflux across the plasma membrane of plant cells

Electrotonic potentials in Aloe vera L.: Effects of intercellular and external electrodes arrangement

Electrical signal propagation within and between tomato plants

Contact Info

Product

Resources

About

Biochemical and biophysical pH clamp controlling Net H⁺ efflux across the plasma membrane of plant cells

Biochemical and biophysical pH clamp controlling Net H⁺ efflux across the plasma membrane of plant cells