Open AccessA sulphur deficiency‐induced gene, sdi1 , involved in the utilization of stored sulphate pools under sulphur‐limiting conditions has potential as a diagnostic indicator of sulphur nutritional status
Author(s) -
Howarth Jonathan R.,
Parmar Saroj,
Barraclough Peter B.,
Hawkesford Malcolm J.
Publication year - 2009
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/j.1467-7652.2008.00391.x
Subject(s) - biology , sulfur , gene , sulfur metabolism , nutrient , mutant , gene expression , arabidopsis , arabidopsis thaliana , limiting , genomic dna , botany , biochemistry , genetics , ecology , chemistry , mechanical engineering , organic chemistry , engineering
Summary A sulphate deficiency‐induced gene, sdi1 , has been identified by cDNA‐amplified fragment length polymorphism (AFLP) analysis utilizing field‐grown, nutrient‐deficient wheat ( Triticum aestivum var. Hereward). The expression of sdi1 was specifically induced in leaf and root tissues in response to sulphate deficiency, but was not induced by nitrogen, phosphorus, potassium or magnesium deficiency. Expression was also shown to increase in plant tissues as the external sulphate concentration in hydroponically grown plants was reduced from 1.0 to 0.0 m m . On this basis, sdi1 gene expression has potential as a sensitive indicator of sulphur nutritional status in wheat. Genome‐walking techniques were used to clone the 2.7‐kb region upstream of sdi1 from genomic DNA, revealing several cis ‐element motifs previously identified as being associated with sulphur responses in plants. The Arabidopsis thaliana gene most highly homologous to sdi1 is At5g48850, which was also demonstrated to be induced by sulphur deficiency, an observation confirmed by the analysis of microarray data available in the public domain. The expression of Atsdi1 was induced more rapidly than previously characterized sulphur‐responsive genes in the period immediately following the transfer of plants to sulphur‐deficient medium. Atsdi1 T‐DNA ‘knockout’ mutants were shown to maintain higher tissue sulphate concentrations than wild‐type plants under sulphur‐limiting conditions, indicating a role in the utilization of stored sulphate under sulphur‐deficient conditions. The structural features of the sdi1 gene and its application in the genetic determination of the sulphur nutritional status of wheat crops are discussed.