Expression of TASK and TREK, two-pore domain K+ channels, in human myometrium.
Two-pore domain K+ channels are an emerging family of K+ channels that may contribute to setting membrane potential in both electrically excitable and non-excitable cells and, as such, influence cellular function. The human uteroplacental unit contains both excitable (e.g. myometrial) and non-excitable cells, whose function depends upon the activity of K+ channels. We have therefore investigated the expression of two members of this family, TWIK (two-pore domain weak inward rectifying K+ channel)-related acid-sensitive K+ channel (TASK) and TWIK-related K+ channel (TREK) in human myometrium. Using RT-PCR the mRNA expression of TASK and TREK isoforms was examined in myometrial tissue from pregnant women. mRNAs encoding TASK1, 4 and 5 and TREK1 were detected whereas weak or no signals were observed for TASK2, TASK3 and TREK2. Western blotting for TASK1 gave two bands of approximately 44 and 65 kDa, whereas TREK1 gave bands of approximately 59 and 90 kDa in myometrium from pregnant women. TASK1 and TREK1 immunofluorescence was prominent in intracellular and plasmalemmal locations within myometrial cells. Therefore, we conclude that the human myometrium is a site of expression for the two-pore domain K+ channel proteins TASK1 and TREK1.
Bai
Xilian
X
Maternal and Fetal Health Research Centre, St Mary's Hospital, University of Manchester, Hathersage Road, Manchester M13 0JH, UK.
Bugg
George J
GJ
Greenwood
Susan L
SL
Glazier
Jocelyn D
JD
Sibley
Colin P
CP
Baker
Philip N
PN
Taggart
Michael J
MJ
Fyfe
Gregor K
GK
D015153:Blotting, Western / Q000379:methods; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008564:Membrane Potentials; D009215:Myometrium / Q000737:chemistry* / Q000166:cytology / Q000378:metabolism; D009419:Nerve Tissue Proteins; D024683:Potassium Channels, Tandem Pore Domain / Q000032:analysis* / Q000235:genetics; D011247:Pregnancy / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
D009419:Nerve Tissue Proteins; D024683:Potassium Channels, Tandem Pore Domain; D012333:RNA, Messenger; C103742:potassium channel protein TREK-1; C420132:potassium channel subfamily K member 3