Non-essential contribution of LRRC8A to volume regulation

  • Lalida Sirianant
  • Podchanart Wanitchakool
  • Jiraporn Ousingsawat
  • Roberta Benedetto
  • Anna Zormpa
  • Ines Cabrita
  • Rainer Schreiber
  • Karl Kunzelmann
Ion channels, receptors and transporters


Volume regulation is an essential property of any living cell and needs to be tightly controlled. While different types of K+ channels have been found to participate in the regulation of cell volume, the newly identified volume-regulated anion channel (VRAC) LRRC8 has been claimed to be essential for volume regulation. In unbiased genome-wide small interfering RNA (siRNA) screens, two independent studies identified LRRC8A/Swell1 as an essential component of VRAC, thus being indispensable for cellular volume regulation. We reanalyzed the role of LRRC8A for VRAC and regulatory volume decrease (RVD) in several cell types and under various conditions. While the role of LRRC8A for VRAC and its contribution to RVD is confirmed, we find that it is not essential for swelling-activated anion currents or cellular volume regulation, or apoptotic cell shrinkage. The contribution of LRRC8A is variable and largely depending on the cell type.


LRRC8A VRAC Volume-activated anion channels Volume regulation: regulatory volume decrease RVD, apoptotic volume decrease AVD 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Lalida Sirianant
    • 1
  • Podchanart Wanitchakool
    • 1
  • Jiraporn Ousingsawat
    • 1
  • Roberta Benedetto
    • 1
  • Anna Zormpa
    • 1
  • Ines Cabrita
    • 1
  • Rainer Schreiber
    • 1
  • Karl Kunzelmann
    • 1
  1. 1.Institut für PhysiologieUniversität RegensburgRegensburgGermany

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