Unknown

Dataset Information

0

Plant K+ channel alpha-subunits assemble indiscriminately.


ABSTRACT: In plants a large diversity of inwardly rectifying K+ channels (K(in) channels) has been observed between tissues and species. However, only three different types of voltage-dependent plant K+ uptake channel subfamilies have been cloned so far; they relate either to KAT1, AKT1, or AtKC1. To explore the mechanisms underlying the channel diversity, we investigated the assembly of plant inwardly rectifying alpha-subunits. cRNA encoding five different K+ channel alpha-subunits of the three subfamilies (KAT1, KST1, AKT1, SKT1, and AtKC1) which were isolated from different tissues, species, and plant families (Arabidopsis thaliana and Solanum tuberosum) was reciprocally co-injected into Xenopus oocytes. We identified plant K+ channels as multimers. Moreover, using K+ channel mutants expressing different sensitivities to voltage, Cs+, Ca2+, and H+, we could prove heteromers on the basis of their altered voltage and modulator susceptibility. We discovered that, in contrast to animal K+ channel alpha-subunits, functional aggregates of plant K(in) channel alpha-subunits assembled indiscriminately. Interestingly, AKT-type channels from A. thaliana and S. tuberosum, which as homomers were electrically silent in oocytes after co-expression, mediated K+ currents. Our findings suggest that K+ channel diversity in plants results from nonselective heteromerization of different alpha-subunits, and thus depends on the spatial segregation of individual alpha-subunit pools and the degree of temporal overlap and kinetics of expression.

SUBMITTER: Dreyer I 

PROVIDER: S-EPMC1184408 | biostudies-other | 1997 May

REPOSITORIES: biostudies-other

altmetric image

Publications

Plant K+ channel alpha-subunits assemble indiscriminately.

Dreyer I I   Antunes S S   Hoshi T T   Müller-Röber B B   Palme K K   Pongs O O   Reintanz B B   Hedrich R R  

Biophysical journal 19970501 5


In plants a large diversity of inwardly rectifying K+ channels (K(in) channels) has been observed between tissues and species. However, only three different types of voltage-dependent plant K+ uptake channel subfamilies have been cloned so far; they relate either to KAT1, AKT1, or AtKC1. To explore the mechanisms underlying the channel diversity, we investigated the assembly of plant inwardly rectifying alpha-subunits. cRNA encoding five different K+ channel alpha-subunits of the three subfamili  ...[more]

Similar Datasets

| S-EPMC6052497 | biostudies-literature
| S-EPMC2849892 | biostudies-literature
| S-EPMC4487825 | biostudies-literature
| S-EPMC4193333 | biostudies-literature
| S-EPMC2662182 | biostudies-literature
| S-EPMC1413874 | biostudies-other
| S-EPMC3006222 | biostudies-literature
| S-EPMC3181431 | biostudies-literature