RRC ID |
49626
|
Author |
Homareda H, Otsu M, Yamamoto S, Ushimaru M, Ito S, Fukutomi T, Jo T, Eishi Y, Hara Y.
|
Title |
A possible mechanism for low affinity of silkworm Na+/K+-ATPase for K.
|
Journal |
J Bioenerg Biomembr
|
Abstract |
The affinity for K+ of silkworm nerve Na+/K+-ATPase is markedly lower than that of mammalian Na+/K+-ATPase (Homareda 2010). In order to obtain clues on the molecular basis of the difference in K+ affinities, we cloned cDNAs of silkworm (Bombyx mori) nerve Na+/K+-ATPase α and β subunits, and analyzed the deduced amino acid sequences. The molecular masses of the α and β subunits were presumed to be 111.5 kDa with ten transmembrane segments and 37.7 kDa with a single transmembrane segment, respectively. The α subunit showed 75% identity and 93% homology with the pig Na+/K+-ATPase α1 subunit. On the other hand, the amino acid identity of the β subunit with mammalian counterparts was as low as 30%. Cloned α and β cDNAs were co-expressed in cultured silkworm ovary-derived cells, BM-N cells, which lack endogenous Na+/K+-ATPase. Na+/K+-ATPase expressed in the cultured cells showed a low affinity for K+ and a high affinity for Na+, characteristic of the silkworm nerve Na+/K+-ATPase. These results suggest that the β subunit is responsible for the affinity for K+ of Na+/K+-ATPase.
|
Volume |
49(6)
|
Pages |
463-472
|
Published |
2017-12-1
|
DOI |
10.1007/s10863-017-9729-5
|
PII |
10.1007/s10863-017-9729-5
|
PMID |
29047027
|
MeSH |
Amino Acid Sequence
Animals
Bombyx / enzymology*
DNA, Complementary
Potassium / metabolism*
Protein Binding
Protein Subunits / metabolism
Protein Subunits / physiology
Sodium-Potassium-Exchanging ATPase / chemistry*
Sodium-Potassium-Exchanging ATPase / metabolism
|
IF |
2.524
|
Times Cited |
0
|
Resource |
Silkworms |
p20 |
Human and Animal Cells |
BM-N(RCB0457) |