Linked Life Data

18550686

Source:http://linkedlifedata.com/resource/pubmed/id/18550686

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2008-8-5
pubmed:abstractText
Many plant species avoid the phytotoxic effects of aluminum (Al) by exuding dicarboxylic and tricarboxylic acids that chelate and immobilize Al(3+) at the root surface, thus preventing it from entering root cells. Several novel genes that encode membrane transporters from the ALMT and MATE families recently were cloned and implicated in mediating the organic acid transport underlying this Al tolerance response. Given our limited understanding of the functional properties of ALMTs, in this study a detailed characterization of the transport properties of TaALMT1 (formerly named ALMT1) from wheat (Triticum aestivum) expressed in Xenopus laevis oocytes was conducted. The electrophysiological findings are as follows. Although the activity of TaALMT1 is highly dependent on the presence of extracellular Al(3+) (K(m1/2) of approximately 5 microm Al(3+) activity), TaALMT1 is functionally active and can mediate ion transport in the absence of extracellular Al(3+). The lack of change in the reversal potential (E(rev)) upon exposure to Al(3+) suggests that the "enhancement" of TaALMT1 malate transport by Al is not due to alteration in the transporter's selectivity properties but is solely due to increases in its anion permeability. The consistent shift in the direction of the E(rev) as the intracellular malate activity increases indicates that TaALMT1 is selective for the transport of malate over other anions. The estimated permeability ratio between malate and chloride varied between 1 and 30. However, the complex behavior of the E(rev) as the extracellular Cl(-) activity was varied indicates that this estimate can only be used as a general guide to understanding the relative affinity of TaALMT1 for malate, representing only an approximation of those expected under physiologically relevant ionic conditions. TaALMT1 can also mediate a large anion influx (i.e. outward currents). TaALMT1 is permeable not only to malate but also to other physiologically relevant anions such as Cl(-), NO(3)(-), and SO(4)(2-) (to a lesser degree).
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-10398755, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-10694252, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-11038549, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-11154337, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-11244125, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-11351102, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-12114573, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-14871306, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-1528115, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-1528120, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-15377228, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-15471989, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-15591441, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-15769806, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-16391684, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-16441747, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-16740662, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-17028155, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-17418140, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-17721535, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-18005230, http://linkedlifedata.com/resource/pubmed/commentcorrection/18550686-18069943
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
147
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2131-46
pubmed:dateRevised
2010-9-22
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Novel properties of the wheat aluminum tolerance organic acid transporter (TaALMT1) revealed by electrophysiological characterization in Xenopus Oocytes: functional and structural implications.
pubmed:affiliation
United States Department of Agriculture-Agricultural Research Service, Cornell University, Ithaca, New York 14853-2901, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't