Cell-specific expression of the mercury-insensitive plasma-membrane aquaporin NtAQP1 from Nicotiana tabacum.
The aquaporin NtAQP1 from Nicotiana tabacum L. is insensitive to heavy-metal ions. In addition to water, the transport of urea or glycerol is facilitated by this plasma-membrane-located water channel. Northern hybridization and whole-mount in situ hybridization revealed a high steady-state level of NtAQP1-RNA in roots, a decreased content in shoots and a low content in leaves. By immunolocalization with an antibody targeted to the N-terminus of the aquaporin, the localization of NtAQP1-protein at sites of expected high water transport rates from and to the apoplast or symplast could be demonstrated. The specific pattern of NtAQP1 distribution in petioles strongly indicates a transcellular movement of water.
Otto
B
B
Julius-van-Sachs-Institut für Biowissenschaften, Molekulare Pflazenphysiologie und Biophysik, Universität Würzburg, Germany.
Kaldenhoff
R
R
D051398:Aquaporin 1; D020346:Aquaporins / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D002462:Cell Membrane / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D005990:Glycerol / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology / Q000378:metabolism; D018520:Plant Shoots / Q000166:cytology / Q000378:metabolism; D010947:Plants, Toxic; D014026:Nicotiana / Q000166:cytology / Q000187:drug effects / Q000235:genetics*; D014508:Urea / Q000378:metabolism
D020346:Aquaporins; D051398:Aquaporin 1; D014508:Urea; D005990:Glycerol