A putative role for the plasma membrane potential in the control of the expression of the gene encoding the tomato high-affinity potassium transporter HAK5

A putative role for the plasma membrane potential in the control of the expression of the gene... A chimeric CaHAK1–LeHAK5 transporter with only 15 amino acids of CaHAK1 in the N-terminus mediates high-affinity K+ uptake in yeast cells. Kinetic and expression analyses strongly suggest that LeHAK5 mediates a significant proportion of the high-affinity K+ uptake shown by K+-starved tomato (Solanum lycopersicum) plants. The development of high-affinity K+ uptake, putatively mediated by LeHAK5, was correlated with increased LeHAK5 mRNA levels and a more negative electrical potential difference across the plasma membrane of root epidermal and cortical cells. However, this increase in high-affinity K+ uptake was not correlated with the root K+ content. Thus, (i) growth conditions that result in a hyperpolarized root plasma membrane potential, such as K+ starvation or growth in the presence of NH4 +, but which do not decrease the K+ content, lead to increased LeHAK5 expression; (ii) the presence of NaCl in the growth solution, which prevents the hyperpolarization induced by K+ starvation, also prevents LeHAK5 expression. Moreover, once the gene is induced, depolarization of the plasma membrane potential then produces a decrease in the LeHAK5 mRNA. On the basis of these results, we propose that the plant membrane electrical potential plays a role in the regulation of the expression of this gene encoding a high-affinity K+ transporter. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Plant Molecular Biology Springer Journals

A putative role for the plasma membrane potential in the control of the expression of the gene encoding the tomato high-affinity potassium transporter HAK5

Loading next page...
 
/lp/springer_journal/a-putative-role-for-the-plasma-membrane-potential-in-the-control-of-HbyayZQhTH
Publisher
Springer Netherlands
Copyright
Copyright © 2008 by Springer Science+Business Media B.V.
Subject
Life Sciences; Plant Pathology; Biochemistry, general; Plant Sciences
ISSN
0167-4412
eISSN
1573-5028
D.O.I.
10.1007/s11103-008-9388-3
Publisher site
See Article on Publisher Site

Abstract

A chimeric CaHAK1–LeHAK5 transporter with only 15 amino acids of CaHAK1 in the N-terminus mediates high-affinity K+ uptake in yeast cells. Kinetic and expression analyses strongly suggest that LeHAK5 mediates a significant proportion of the high-affinity K+ uptake shown by K+-starved tomato (Solanum lycopersicum) plants. The development of high-affinity K+ uptake, putatively mediated by LeHAK5, was correlated with increased LeHAK5 mRNA levels and a more negative electrical potential difference across the plasma membrane of root epidermal and cortical cells. However, this increase in high-affinity K+ uptake was not correlated with the root K+ content. Thus, (i) growth conditions that result in a hyperpolarized root plasma membrane potential, such as K+ starvation or growth in the presence of NH4 +, but which do not decrease the K+ content, lead to increased LeHAK5 expression; (ii) the presence of NaCl in the growth solution, which prevents the hyperpolarization induced by K+ starvation, also prevents LeHAK5 expression. Moreover, once the gene is induced, depolarization of the plasma membrane potential then produces a decrease in the LeHAK5 mRNA. On the basis of these results, we propose that the plant membrane electrical potential plays a role in the regulation of the expression of this gene encoding a high-affinity K+ transporter.

Journal

Plant Molecular BiologySpringer Journals

Published: Aug 27, 2008

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve Freelancer

DeepDyve Pro

Price
FREE
$49/month

$360/year
Save searches from
Google Scholar,
PubMed
Create lists to
organize your research
Export lists, citations
Read DeepDyve articles
Abstract access only
Unlimited access to over
18 million full-text articles
Print
20 pages/month
PDF Discount
20% off