start-ver=1.4 cd-journal=joma no-vol=10 cd-vols= no-issue=10 article-no= start-page=2006 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2021 dt-pub=20210924 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Identification and Characterization of Rice OsHKT1;3 Variants en-subtitle= kn-subtitle= en-abstract= kn-abstract=In rice, the high-affinity K+ transporter, OsHKT1;3, functions as a Na+-selective transporter. mRNA variants of OsHKT1;3 have been reported previously, but their functions remain unknown. In this study, five OsHKT1;3 variants (V1-V5) were identified from japonica rice (Nipponbare) in addition to OsHKT1;3_FL. Absolute quantification qPCR analyses revealed that the transcript level of OsHKT1;3_FL was significantly higher than other variants in both the roots and shoots. Expression levels of OsHKT1;3_FL, and some variants, increased after 24 h of salt stress. Two electrode voltage clamp experiments in a heterologous expression system using Xenopus laevis oocytes revealed that oocytes expressing OsHKT1;3_FL and all of its variants exhibited smaller Na+ currents. The presented data, together with previous data, provide insights to understanding how OsHKT family members are involved in the mechanisms of ion homeostasis and salt tolerance in rice.

en-copyright= kn-copyright= en-aut-name=ImranShahin en-aut-sei=Imran en-aut-mei=Shahin kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=TsuchiyaYoshiyuki en-aut-sei=Tsuchiya en-aut-mei=Yoshiyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=TranSen Thi Huong en-aut-sei=Tran en-aut-mei=Sen Thi Huong kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=KatsuharaMaki en-aut-sei=Katsuhara en-aut-mei=Maki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Institute of Plant Science and Resources, Okayama University kn-affil= affil-num=2 en-affil=Institute of Plant Science and Resources, Okayama University kn-affil= affil-num=3 en-affil=Institute of Plant Science and Resources, Okayama University kn-affil= affil-num=4 en-affil=Institute of Plant Science and Resources, Okayama University kn-affil= en-keyword=Na+ transport kn-keyword=Na+ transport en-keyword=rice kn-keyword=rice en-keyword=OsHKT1 kn-keyword=OsHKT1 en-keyword=3 kn-keyword=3 en-keyword=mRNA variants kn-keyword=mRNA variants en-keyword=TEVC kn-keyword=TEVC END start-ver=1.4 cd-journal=joma no-vol=21 cd-vols= no-issue=19 article-no= start-page=7135 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200927 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=A Survey of Barley PIP Aquaporin Ionic Conductance Reveals Ca2+-Sensitive HvPIP2;8 Na+ and K+ Conductance en-subtitle= kn-subtitle= en-abstract= kn-abstract=Some plasma membrane intrinsic protein (PIP) aquaporins can facilitate ion transport. Here we report that one of the 12 barley PIPs (PIP1 and PIP2) tested, HvPIP2;8, facilitated cation transport when expressed in Xenopus laevis oocytes. HvPIP2;8-associated ion currents were detected with Na+ and K+, but not Cs+, Rb+, or Li+, and was inhibited by Ba2+, Ca2+, and Cd2+ and to a lesser extent Mg2+, which also interacted with Ca2+. Currents were reduced in the presence of K+, Cs+, Rb+, or Li+ relative to Na+ alone. Five HvPIP1 isoforms co-expressed with HvPIP2;8 inhibited the ion conductance relative to HvPIP2;8 alone but HvPIP1;3 and HvPIP1;4 with HvPIP2;8 maintained the ion conductance at a lower level. HvPIP2;8 water permeability was similar to that of a C-terminal phosphorylation mimic mutant HvPIP2;8 S285D, but HvPIP2;8 S285D showed a negative linear correlation between water permeability and ion conductance that was modified by a kinase inhibitor treatment. HvPIP2;8 transcript abundance increased in barley shoot tissues following salt treatments in a salt-tolerant cultivar Haruna-Nijo, but not in salt-sensitive I743. There is potential for HvPIP2;8 to be involved in barley salt-stress responses, and HvPIP2;8 could facilitate both water and Na+/K+ transport activity, depending on the phosphorylation status. en-copyright= kn-copyright= en-aut-name=Sen Thi HuongTran en-aut-sei=Sen Thi Huong en-aut-mei=Tran kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=HorieTomoaki en-aut-sei=Horie en-aut-mei=Tomoaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=ImranShahin en-aut-sei=Imran en-aut-mei=Shahin kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=QiuJiaen en-aut-sei=Qiu en-aut-mei=Jiaen kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=McGaugheySamantha en-aut-sei=McGaughey en-aut-mei=Samantha kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=ByrtCaitlin S. en-aut-sei=Byrt en-aut-mei=Caitlin S. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=TyermanStephen D. en-aut-sei=Tyerman en-aut-mei=Stephen D. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=KatsuharaMaki en-aut-sei=Katsuhara en-aut-mei=Maki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= affil-num=1 en-affil=Institute of Plant Science and Resources, Okayama University kn-affil= affil-num=2 en-affil=Division of Applied Biology, Faculty of Textile Science and Technology, Shinshu University kn-affil= affil-num=3 en-affil=Institute of Plant Science and Resources, Okayama University kn-affil= affil-num=4 en-affil=Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Institute and School of Agriculture, Food and Wine, The University of Adelaide kn-affil= affil-num=5 en-affil=Research School of Biology, Australian National University kn-affil= affil-num=6 en-affil=Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Institute and School of Agriculture, Food and Wine, The University of Adelaide kn-affil= affil-num=7 en-affil=Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Institute and School of Agriculture, Food and Wine, The University of Adelaide kn-affil= affil-num=8 en-affil=Institute of Plant Science and Resources, Okayama University kn-affil= en-keyword=aquaporins kn-keyword=aquaporins en-keyword=barley kn-keyword=barley en-keyword=ion transport kn-keyword=ion transport en-keyword=oocytes kn-keyword=oocytes en-keyword=plasma membrane intrinsic proteins (PIPs) kn-keyword=plasma membrane intrinsic proteins (PIPs) END start-ver=1.4 cd-journal=joma no-vol=9 cd-vols= no-issue=1 article-no= start-page=16 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2019 dt-pub=20191221 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Expression and Ion Transport Activity of Rice OsHKT1;1 Variants en-subtitle= kn-subtitle= en-abstract= kn-abstract=OsHKT1;1 in rice, belongs to the high-affinity K+ Transporter family, has been found to be involved in salt tolerance. OsHKT1;1 in japonica rice (Nipponbare) produces mRNA variants, but their functions remain elusive. In salt tolerant rice, Pokkali, eight OsHKT1;1 variants (V1-V8) were identified in addition to the full-length OsHKT1;1 (FL) cDNA. Absolute quantification by qPCR revealed that accumulation of OsHKT1;1-FL mRNA is minor in contrast to that of OsHKT1;1-V1, -V2, -V4, and -V7 mRNAs, all of which are predominant in shoots, while only V1 and V7 mRNAs are predominant in roots. Two electrode voltage clamp (TEVC) experiments using Xenopus laevis oocytes revealed that oocytes-expressing OsHKT1;1-FL from Pokkali exhibited inward-rectified currents in the presence of 96 mM Na+ as reported previously. Further TEVC analyses indicated that six of eight OsHKT1;1 variants elicited currents in a Na+ or a K+ bath solution. OsHKT1;1-V6 exhibited a similar inward rectification to the FL protein. Contrastingly, however, the rests mediated bidirectional currents in both Na+ and K+ bath solutions. These data suggest possibilities that novel mechanisms regulating the transport activity of OsHKT1;1 might exist, and that OsHKT1;1 variants might also carry out distinct physiological roles either independently or in combination with OsHKT1;1-FL. en-copyright= kn-copyright= en-aut-name=ImranShahin en-aut-sei=Imran en-aut-mei=Shahin kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=HorieTomoaki en-aut-sei=Horie en-aut-mei=Tomoaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KatsuharaMaki en-aut-sei=Katsuhara en-aut-mei=Maki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Institute of Plant Science and Resources, Okayama University kn-affil= affil-num=2 en-affil=Division of Applied Biology, Faculty of the Textile Science and Technology, Shinshu University kn-affil= affil-num=3 en-affil=Institute of Plant Science and Resources, Okayama University kn-affil= en-keyword=HKT kn-keyword=HKT en-keyword=rice kn-keyword=rice en-keyword=salt tolerance kn-keyword=salt tolerance en-keyword=Na+ transport kn-keyword=Na+ transport en-keyword=K+ transport kn-keyword=K+ transport en-keyword=mRNA variants kn-keyword=mRNA variants END start-ver=1.4 cd-journal=joma no-vol=42 cd-vols= no-issue=2 article-no= start-page=437 end-page=447 dt-received= dt-revised= dt-accepted= dt-pub-year=2018 dt-pub=20180716 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=The mechanism of SO2 -induced stomatal closure differs from O3 and CO2 responses and is mediated by nonapoptotic cell death in guard cells. en-subtitle= kn-subtitle= en-abstract= kn-abstract= Plants closing stomata in the presence of harmful gases is believed to be a stress avoidance mechanism. SO2 , one of the major airborne pollutants, has long been reported to induce stomatal closure, yet the mechanism remains unknown. Little is known about the stomatal response to airborne pollutants besides O3 . SLOW ANION CHANNEL-ASSOCIATED 1 (SLAC1) and OPEN STOMATA 1 (OST1) were identified as genes mediating O3 -induced closure. SLAC1 and OST1 are also known to mediate stomatal closure in response to CO2 , together with RESPIRATORY BURST OXIDASE HOMOLOGs (RBOHs). The overlaying roles of these genes in response to O3 and CO2 suggested that plants share their molecular regulators for airborne stimuli. Here, we investigated and compared stomatal closure event induced by a wide concentration range of SO2 in Arabidopsis through molecular genetic approaches. O3 - and CO2 -insensitive stomata mutants did not show significant differences from the wild type in stomatal sensitivity, guard cell viability, and chlorophyll content revealing that SO2 -induced closure is not regulated by the same molecular mechanisms as for O3 and CO2 . Nonapoptotic cell death is shown as the reason for SO2 -induced closure, which proposed the closure as a physicochemical process resulted from SO2 distress, instead of a biological protection mechanism. en-copyright= kn-copyright= en-aut-name=Ooi Lia en-aut-sei=Ooi en-aut-mei=Lia kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=MatsuuraTakakazu en-aut-sei=Matsuura en-aut-mei=Takakazu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=MunemasaShintaro en-aut-sei=Munemasa en-aut-mei=Shintaro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=MurataYoshiyuki en-aut-sei=Murata en-aut-mei=Yoshiyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=KatsuharaMaki en-aut-sei=Katsuhara en-aut-mei=Maki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=HirayamaTakashi en-aut-sei=Hirayama en-aut-mei=Takashi kn-aut-name=•½ŽRûéŽu kn-aut-sei=•½ŽR kn-aut-mei=ûéŽu aut-affil-num=6 ORCID= en-aut-name=MoriIzumi C. en-aut-sei=Mori en-aut-mei=Izumi C. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= affil-num=1 en-affil= Institute of Plant Science and Resources, Okayama University kn-affil= affil-num=2 en-affil= Institute of Plant Science and Resources, Okayama University kn-affil= affil-num=3 en-affil=Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=4 en-affil=Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=5 en-affil= Institute of Plant Science and Resources, Okayama University kn-affil= affil-num=6 en-affil= Institute of Plant Science and Resources, Okayama University kn-affil= affil-num=7 en-affil= Institute of Plant Science and Resources, Okayama University kn-affil= en-keyword=airborne pollutants kn-keyword=airborne pollutants en-keyword=nonapoptotic cell death kn-keyword=nonapoptotic cell death en-keyword=stomatal closure kn-keyword=stomatal closure en-keyword=sulfur dioxide kn-keyword=sulfur dioxide END start-ver=1.4 cd-journal=joma no-vol=31 cd-vols= no-issue= article-no= start-page=21 end-page=25 dt-received= dt-revised= dt-accepted= dt-pub-year=2009 dt-pub=200912 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=Cooling effect on buildings by the roof greening at Research Institute for Bioresources, Okayama University kn-title=‰ªŽR‘åŠwŽ‘Œ¹¶•¨‰ÈŠwŒ¤‹†Š‚É‚¨‚¯‚鉮ã—Ή»‚É‚æ‚錚•¨—â‹pŒø‰Ê en-subtitle= kn-subtitle= en-abstract= kn-abstract=Roof greening is known to be environmentally friendly technology. Recently developed new roof greening systems, such as the thin-layer/Excel soil? system and the wetland type greening system, were tested at the roof top of buildings of Research Institute for Bioresources, Okayama University. After a multi-year test, these new systems have been established during high-temperature and less-rainfall summer seasons in the south Okayama region. Data indicated that roof greening effectively reduced the temperature of the concrete surface (more than 10‹C). The room temperature under the green roof was also reduced both in a stock room (up to 6‹C) and in an office room (about 2‹C). We also provided the estimation indicating that this roof greening is useful for the decrease in CO(2) emission through the reduction of the electric power for air-conditioning in the summer. en-copyright= kn-copyright= en-aut-name=KatsuharaMaki en-aut-sei=Katsuhara en-aut-mei=Maki kn-aut-name=ŠŽŒ´^–Ø kn-aut-sei=ŠŽŒ´ kn-aut-mei=^–Ø aut-affil-num=1 ORCID= en-aut-name=TanakamaruShigemi en-aut-sei=Tanakamaru en-aut-mei=Shigemi kn-aut-name=“c’†ŠÛd”ü kn-aut-sei=“c’†ŠÛ kn-aut-mei=d”ü aut-affil-num=2 ORCID= en-aut-name=MoriIzumi C. en-aut-sei=Mori en-aut-mei=Izumi C. kn-aut-name=Xò kn-aut-sei=X kn-aut-mei=ò aut-affil-num=3 ORCID= en-aut-name=TaniAkio en-aut-sei=Tani en-aut-mei=Akio kn-aut-name=’J–¾¶ kn-aut-sei=’J kn-aut-mei=–¾¶ aut-affil-num=4 ORCID= en-aut-name=UtsugiShigeko en-aut-sei=Utsugi en-aut-mei=Shigeko kn-aut-name=‰F“s–ؔɎq kn-aut-sei=‰F“s–Ø kn-aut-mei=”ÉŽq aut-affil-num=5 ORCID= en-aut-name=EnomotoTakashi en-aut-sei=Enomoto en-aut-mei=Takashi kn-aut-name=‰|–{Œh kn-aut-sei=‰|–{ kn-aut-mei=Œh aut-affil-num=6 ORCID= en-aut-name=MaitaniToshihiko en-aut-sei=Maitani en-aut-mei=Toshihiko kn-aut-name=•Ä’Jr•F kn-aut-sei=•Ä’J kn-aut-mei=r•F aut-affil-num=7 ORCID= affil-num=1 en-affil= kn-affil=‰ªŽR‘åŠwŽ‘Œ¹¶•¨‰ÈŠwŒ¤‹†Š affil-num=2 en-affil= kn-affil=‰ªŽR‘åŠwŽ‘Œ¹¶•¨‰ÈŠwŒ¤‹†Š affil-num=3 en-affil= kn-affil=‰ªŽR‘åŠwŽ‘Œ¹¶•¨‰ÈŠwŒ¤‹†Š affil-num=4 en-affil= kn-affil=‰ªŽR‘åŠwŽ‘Œ¹¶•¨‰ÈŠwŒ¤‹†Š affil-num=5 en-affil= kn-affil=‰ªŽR‘åŠwŽ‘Œ¹¶•¨‰ÈŠwŒ¤‹†Š affil-num=6 en-affil= kn-affil=‰ªŽR‘åŠwŽ‘Œ¹¶•¨‰ÈŠwŒ¤‹†Š affil-num=7 en-affil= kn-affil=‰ªŽR‘åŠwŽ‘Œ¹¶•¨‰ÈŠwŒ¤‹†Š en-keyword=Roof greening kn-keyword=Roof greening en-keyword=wetland type greening kn-keyword=wetland type greening en-keyword=thin-Iayer/ Excel soil? system kn-keyword=thin-Iayer/ Excel soil? system en-keyword=cooling effect kn-keyword=cooling effect END start-ver=1.4 cd-journal=joma no-vol=456 cd-vols= no-issue=4 article-no= start-page=687 end-page=691 dt-received= dt-revised= dt-accepted= dt-pub-year=2008 dt-pub=20080626 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Barley plasma membrane intrinsic proteins (PIP aquaporins) as water and CO2 transporters en-subtitle= kn-subtitle= en-abstract= kn-abstract=

We identified barley aquaporins and demonstrated that one, HvPIP2;1, transports water and CO2. Regarding water homeostasis in plants, regulations of aquaporin expression were observed in many plants under several environmental stresses. Under salt stress, a number of plasma membrane-type aquaporins were down-regulated, which can prevent continuous dehydration resulting in cell death. The leaves of transgenic rice plants that expressed the largest amount of HvPIP2;1 showed a 40% increase in internal CO2 conductance compared with leaves of wild-type rice plants. The rate of CO2 assimilation also increased in the transgenic plants. The goal of our plant aquaporin research is to determine the key aquaporin species responsible for water and CO2 transport, and to improve plant water relations, stress tolerance, CO2 uptake or assimilation, and plant productivity via molecular breeding of aquaporins.

en-copyright= kn-copyright= en-aut-name=KatsuharaMaki en-aut-sei=Katsuhara en-aut-mei=Maki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=HanbaYuko T. en-aut-sei=Hanba en-aut-mei=Yuko T. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= affil-num=1 en-affil= kn-affil=Research Institute for Bioresources, Okayama University affil-num=2 en-affil= kn-affil=Center for Bioresource Field Science, Kyoto Institute of Technology en-keyword=barley kn-keyword=barley en-keyword=CO2 kn-keyword=CO2 en-keyword=plant aquaporins kn-keyword=plant aquaporins en-keyword=salt stress kn-keyword=salt stress en-keyword=water transport kn-keyword=water transport END start-ver=1.4 cd-journal=joma no-vol=3 cd-vols= no-issue=2 article-no= start-page=145 end-page=149 dt-received= dt-revised= dt-accepted= dt-pub-year=1995 dt-pub=1995 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=Cloning of PCR-Products Encoding Potassium Channel Proteins from Mesembryanthemum crystallinum kn-title=Mesembryanthemum crystallinum(ice plant)‚É‚¨‚¯‚éƒJƒŠƒEƒ€ƒ`ƒƒƒ“ƒlƒ‹‚ðƒR[ƒh‚·‚éPCRŽY•¨‚̃Nƒ[ƒjƒ“ƒO en-subtitle= kn-subtitle= en-abstract=‘ω–«A‘ÏŠ£«‚Ì‹É‚ß‚Ä‚‚¢ Mesembryanthemum crystallinum ‚©‚çPCR–@‚ð—p‚¢‚ăJƒŠƒEƒ€ƒ`ƒƒƒ“ƒlƒ‹ˆâ“`Žq’f•Ð‚𓾂½B2‚‚̃Nƒ[ƒ“‚ª“Æ—§‚É“¾‚ç‚ꂽ‚ªAŒÝ‚¢‚É‚æ‚­Ž—‚Ä‚¢‚ÄAƒVƒƒCƒkƒiƒYƒi‚̃JƒŠƒEƒ€ƒ`ƒƒƒ“ƒlƒ‹‚Æ‚Í67‚©‚ç88“‚Ì‘Š“¯«‚ðŽ¦‚µ‚½BƒTƒUƒ“ƒnƒCƒuƒŠƒ_ƒCƒ[[ƒVƒ‡ƒ“‚ÌŒ‹‰Ê‚©‚çA¡‰ñ“¾‚ç‚ꂽˆâ“`Žq‚̓Vƒ“ƒOƒ‹ƒRƒs[‚Å‚ ‚èA‚Ü‚½ƒJƒŠƒEƒ€ƒ`ƒƒƒ“ƒlƒ‹ˆâ“`Žqƒtƒ@ƒ~ƒŠ[‚ª‘¶Ý‚·‚é‰Â”\«‚ªŽ¦´‚³‚ꂽB kn-abstract=Gene fragments of potassium channels were cloned from Mesembryanthemum crystallinum by using RT-PCR (reverse transcription-polymerase chain reaction). The two fragments were isolated independently and showed high similarity with each other. About 80% identity was found between the two fragments and potassium-channel genes of Arabidopsis. Southern hybridization indicated that the potassium channel gene may be a single copy gene or that a small gene family of potassium channels exists. en-copyright= kn-copyright= en-aut-name=KatsuharaMaki en-aut-sei=Katsuhara en-aut-mei=Maki kn-aut-name=ŠŽŒ´^–Ø kn-aut-sei=ŠŽŒ´ kn-aut-mei=^–Ø aut-affil-num=1 ORCID= en-aut-name=BohnertHans J. en-aut-sei=Bohnert en-aut-mei=Hans J. kn-aut-name=BohnertHans J. kn-aut-sei=Bohnert kn-aut-mei=Hans J. aut-affil-num=2 ORCID= affil-num=1 en-affil= kn-affil=‰ªŽR‘åŠw affil-num=2 en-affil= kn-affil=‰ªŽR‘åŠw en-keyword=Mesembryanthemum crystallinum kn-keyword=Mesembryanthemum crystallinum en-keyword=Potassium channel kn-keyword=Potassium channel en-keyword=RT-PCR kn-keyword=RT-PCR END