Dataset Information

Identification of Lysine Histidine Transporter 2 as an 1-Aminocyclopropane Carboxylic Acid Transporter in Arabidopsis thaliana by Transgenic Complementation Approach.

ABSTRACT: 1-Aminocyclopropane-1-carboxylic acid (ACC), a biosynthetic precursor of ethylene, has long been proposed to act as a mobile messenger in higher plants. However, little is known about the transport system of ACC. Recently, our genetic characterization of an ACC-resistant mutant with normal ethylene sensitivity revealed that lysine histidine transporter 1 (LHT1) functions as a transporter of ACC. As amino acid transporters might have broad substrate specificity, we hypothesized that other amino acid transporters including LHT1 paralogs might have the ACC-transporter activity. Here, we took a gain-of-function approach by transgenic complementation of lht1 mutant with a selected set of amino acid transporters. When we introduced transgene into the lht1 mutant, the transgenic expression of LHT2, but not of LHT3 or amino acid permease 5 (AAP5), restored the ACC resistance phenotype of the lht1 mutant. The result provides genetic evidence that some, if not all, amino acid transporters in Arabidopsis can function as ACC transporters. In support, when expressed in Xenopus laevis oocytes, both LHT1 and LHT2 exhibited ACC-transporting activity, inducing inward current upon addition of ACC. Interestingly, the transgenic expression of LHT2, but not of LHT3 or AAP5, could also suppress the early senescence phenotypes of the lht1 mutant. Taking together, we propose that plants have evolved a multitude of ACC transporters based on amino acid transporters, which would contribute to the differential distribution of ACC under various spatiotemporal contexts.

SUBMITTER: Choi J

PROVIDER: S-EPMC6749071 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Identification of Lysine Histidine Transporter 2 as an 1-Aminocyclopropane Carboxylic Acid Transporter in <i>Arabidopsis thaliana</i> by Transgenic Complementation Approach.

Choi Jungki J Eom Sanung S Shin Kihye K Lee Rin-A RA Choi Soobin S Lee Jun-Ho JH Lee Sumin S Soh Moon-Soo MS

Frontiers in plant science 20190911

1-Aminocyclopropane-1-carboxylic acid (ACC), a biosynthetic precursor of ethylene, has long been proposed to act as a mobile messenger in higher plants. However, little is known about the transport system of ACC. Recently, our genetic characterization of an ACC-resistant mutant with normal ethylene sensitivity revealed that lysine histidine transporter 1 (LHT1) functions as a transporter of ACC. As amino acid transporters might have broad substrate specificity, we hypothesized that other amino a ...[more]

PMID: 31572413

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Project description:Using microarray technology and a set of chickpea (Cicer arietinum L.) unigenes and grasspea (Lathyrus sativus L.) ESTs, chickpea responses to treatments with the defence signalling compounds salicylic acid (SA), methyl jasmonate (MeJA), and aminocyclopropane carboxylic acid (ACC) were studied in four chickpea genotypes with ranging levels of resistance to ascochyta blight (Ascochyta rabiei (Pass.) L.). The experimental system minimized environmental effects and was conducted in reference design, where samples from untreated controls acted as references against post-treatment samples. Robust data quality was achieved through the use of three biological replicates (including a dye-swap), the inclusion of negative controls, and strict selection criteria for differentially expressed genes including a fold change cut-off determined by self-to-self hybridizations, Students t test and multiple testing correction (P<0.05). Microarray observations were also validated by quantitative RT-PCR. The time-course expression patterns of 715 experimental microarray features resulted in differential expression of 425 genes in at least one condition. The A. rabiei resistant chickpea genotypes showed a more substantial range of defence-related gene induction by all treatments, indicating that they may possess stronger abilities to resist infection. Further, the involvement of SA, MeJA, and ACC signalling was identified for the regulation of some important A. rabiei responsive genes, as well as cross-talk between these pathways. This study also found evidence to suggest the involvement of A. rabiei-specific signalling mechanisms for the induction of several genes that were previously implicated in A. rabiei resistance. Overall, this study characterised the regulatory mechanisms of many chickpea genes that may be important in defence against various pathogens, as well as other cellular functions. Although the size of the microarray was limited, the results provided novel insights to the molecular control of chickpea cellular processes, which may assist the understanding of chickpea defence mechanisms and allow enhanced development of disease resistant cultivars. Keywords: time course defence-signalling teatment analysis

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Dataset Information

Identification of Lysine Histidine Transporter 2 as an 1-Aminocyclopropane Carboxylic Acid Transporter in Arabidopsis thaliana by Transgenic Complementation Approach.

Publications

Identification of Lysine Histidine Transporter 2 as an 1-Aminocyclopropane Carboxylic Acid Transporter in <i>Arabidopsis thaliana</i> by Transgenic Complementation Approach.

Similar Datasets

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