Chlorella virus MT325 encodes water and potassium channels that interact synergistically.
Fast and selective transport of water through cell membranes is facilitated by water channels. Water channels belonging to the major intrinsic proteins (MIPs) family have been found in all three domains of life, Archaea, Bacteria, and Eukarya. Here we show that Chlorella virus MT325 has a water channel gene, aqpv1, that forms a functional aquaglyceroporin in oocytes. aqpv1 is transcribed during infection together with MT325 kcv, a gene encoding a previously undescribed type of viral potassium channel. Coexpression of AQPV1 and MT325-Kcv in Xenopus oocytes synergistically increases water transport, suggesting a possible concerted action of the two channels in the infection cycle. The two channels operate by a thermodynamically coupled mechanism that simultaneously alters water conductance and driving force for water movement. Considering the universal role of osmosis, this mechanism is relevant to any cell coexpressing water and potassium channels and could have pathological as well as basic physiological relevance.
Dipartimento di Biologia and Istituto di Biofisica-Consiglio Nazionale delle Ricerche, Università degli Studi di Milano, Via Celoria 26, 20133 Milan, Italy.
Sabrina
S
Gazzarrini
Ming
M
Kang
Svetlana
S
Epimashko
James L
JL
Van Etten
Jack
J
Dainty
Gerhard
G
Thiel
Anna
A
Moroni
D000595:Amino Acid Sequence; D000818:Animals; D051397:Aquaglyceroporins / Q000737:chemistry / Q000235:genetics*; D004267:DNA Viruses / Q000235:genetics* / Q000378:metabolism; D005814:Genes, Viral; D008969:Molecular Sequence Data; D009995:Osmosis; D015221:Potassium Channels / Q000737:chemistry / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D014867:Water / Q000378:metabolism*; D014981:Xenopus
D051397:Aquaglyceroporins; D015221:Potassium Channels; D014867:Water