PMID- 10455019
OWN - NLM
STAT- MEDLINE
DCOM- 19991101
LR  - 20191210
IS  - 0264-6021 (Print)
IS  - 0264-6021 (Linking)
VI  - 342 ( Pt 2)
DP  - 1999 Sep 1
TI  - Inwardly rectifying K+ channel Kir7.1 is highly expressed in thyroid follicular
      cells, intestinal epithelial cells and choroid plexus epithelial cells:
      implication for a functional coupling with Na+,K+-ATPase.
PG  - 329-36
AB  - A novel inwardly rectifying K+ channel, Kir7.1, with unique pore properties, was 
      cloned recently. Working in the field of osmoregulation, we have also identified 
      the same human and rat channel and found that the channel is unique not only in
      its pore sequence but also in its dense localization in the follicular cells of
      the thyroid gland. Northern blot analysis revealed that the channel message was
      abundantly expressed in the thyroid gland and small intestine, and moderately in 
      the kidney, stomach, spinal cord and brain. Immunohistochemistry of the rat
      thyroid, intestine and choroid plexus demonstrated the expression of the channel 
      protein in the follicular cells and epithelial cells, suggesting a role in the
      regulation of the ion-transporting functions of these specialized cells. The
      unique pore properties of Kir7.1 make it a strong candidate for the hypothetical 
      low-conductance K+ channel that is functionally coupled with Na+,K(+)-ATPase by
      recycling K+. We therefore further examined the co-localization of Kir7.1 and
      Na+,K(+)-ATPase and found that both are localized in the basolateral membrane of 
      the thyroid follicular cell; in the choroid plexus, which is known to be unique
      in having Na+,K(+)-ATPase in the apical side of the epithelial cells, Kir7.1 was 
      found in the apical membrane, implying a close functional coupling between the
      channel and Na+,K(+)-ATPase.
FAU - Nakamura, N
AU  - Nakamura N
AD  - Department of Biological Sciences, Tokyo Institute of Technology, Yokohama
      226-8501, Japan.
FAU - Suzuki, Y
AU  - Suzuki Y
FAU - Sakuta, H
AU  - Sakuta H
FAU - Ookata, K
AU  - Ookata K
FAU - Kawahara, K
AU  - Kawahara K
FAU - Hirose, S
AU  - Hirose S
LA  - eng
SI  - GENBANK/AB013889
SI  - GENBANK/AB013890
SI  - GENBANK/AB013891
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Biochem J
JT  - The Biochemical journal
JID - 2984726R
RN  - 0 (Potassium Channels)
RN  - 0 (Potassium Channels, Inwardly Rectifying)
RN  - EC 7.2.2.13 (Sodium-Potassium-Exchanging ATPase)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Cell Line
MH  - Choroid Plexus/metabolism
MH  - Epithelial Cells/metabolism
MH  - Female
MH  - Gene Expression
MH  - Humans
MH  - Immunohistochemistry
MH  - Intestinal Mucosa/metabolism
MH  - Male
MH  - Molecular Sequence Data
MH  - Potassium Channels/*genetics/*metabolism
MH  - *Potassium Channels, Inwardly Rectifying
MH  - Pregnancy
MH  - Rats
MH  - Sequence Homology, Amino Acid
MH  - Sodium-Potassium-Exchanging ATPase/*metabolism
MH  - Thyroid Gland/metabolism
MH  - Tissue Distribution
PMC - PMC1220469
EDAT- 1999/08/24 00:00
MHDA- 1999/08/24 00:01
CRDT- 1999/08/24 00:00
PHST- 1999/08/24 00:00 [pubmed]
PHST- 1999/08/24 00:01 [medline]
PHST- 1999/08/24 00:00 [entrez]
PST - ppublish
SO  - Biochem J. 1999 Sep 1;342 ( Pt 2):329-36.