Identification of miR390-TAS3-ARF pathway in response to salt stress in Helianthus tuberosus L.

MicroRNA390 (miR390), an ancient and highly conserved miRNA family in land plants, plays multiple roles in plant growth, development and stress responses. In this study, we isolated and identified MIR390, miR390, TAS3a/b/c, tasiARF-1/2/3 (trans-acting small interfering RNAs influencing Auxin Response Factors) and ARF2/3/4 in Jerusalem artichoke (Helianthus tuberosus L.).

Identification of a group of XTHs genes responding to heavy metal mercury, salinity and drought stresses in Medicago truncatula.

Xyloglucan endotransglucosylase/hydrolases (XTH) are one of the key enzymes regulating cell wall construction, extension and metabolism. In the study, 44 XTH protein genes from Medicago truncatula genome were identified using bioinformatics, microarray and RT-PCR. Each XTH was showed to possess a highly conserved domain ((D/N)-E-(I/L/F/V)-D-(F/I/L)-E-(F/L)-L-G), and most of XTHs possess four Cys in the C terminal region, which suggests the potential for generating disulfide bonds.

A cotton miRNA is involved in regulation of plant response to salt stress.

The present study functionally identified a new microRNA (microRNA ovual line 5, miRNVL5) with its target gene GhCHR from cotton (Gossypium hirsutum). The sequence of miRNVL5 precursor is 104 nt long, with a well developed secondary structure. GhCHR contains two DC1 and three PHD Cys/His-rich domains, suggesting that GhCHR encodes a zinc-finger domain-containing transcription factor.

The F-box family genes as key elements in response to salt, heavy mental, and drought stresses in Medicago truncatula.

F-box protein is a subunit of Skp1-Rbx1-Cul1-F-box protein (SCF) complex with typically conserved F-box motifs of approximately 40 amino acids and is one of the largest protein families in eukaryotes. F-box proteins play critical roles in selective and specific protein degradation through the 26S proteasome. In this study, we bioinformatically identified 972 putative F-box proteins from Medicago truncatula genome.

Molecular dissection of mercury-responsive transcriptome and sense/antisense genes in Medicago truncatula.

We described a newly developed approach, namely next-generation tag sequencing, to identify global gene transcripts and complexity regulated by heavy metals in Medicago truncatula. Two cDNA libraries were generated from M. truncatula seedlings: treated and non-treated with the toxic heavy metal mercury Hg(II).

Genome-wide identification of Brassica napus microRNAs and their targets in response to cadmium.

MicroRNAs (miRNAs) are a distinct class of small RNAs in plants that not only regulate biological processes but also regulate response to environmental stresses. The toxic heavy metal cadmium (Cd) induces expression of several miRNAs in rapeseed (Brassica napus), but it is not known on a genome-wide scale how the expression of miRNAs and their target genes, is regulated by Cd. In this study, four small RNA libraries and four degradome libraries were constructed from Cd-treated and non-Cd-treated roots and shoots of B.

Molecular dissection of atrazine-responsive transcriptome and gene networks in rice by high-throughput sequencing.

The residue of atrazine (a herbicide) has become hazards in environments due to its intensive use. However, its molecular toxicity to on plants and human beings is not fully understood. In this study, we performed high-throughput sequencing of atrazine-exposed rice (Oryza sativa) to analyze global expression and complexity of genes in the crop.

Genome-wide identification of Medicago truncatula microRNAs and their targets reveals their differential regulation by heavy metal.

We adopted a deep sequencing approach developed by Solexa (Illumina Inc., San Diego, CA, USA) to investigate global expression and complexity of microRNAs (miRNAs) and their targets from Medicago truncatula. Two small RNA libraries and two degradome libraries were constructed from mercury (Hg)-treated and Hg-free M.

Bioinformatic identification and expression analysis of new microRNAs from Medicago truncatula.

MicroRNAs (miRNAs) are a class of non-protein coding small RNAs that regulate gene post-transcriptional expression in plants and animals. Although more than 1280 miRNAs in plant kingdom have been discovered thus far, only a handful of plant miRNAs has been intensively identified. The legume Medicago truncatula is a model system widely used to investigate gene transcription or post-transcriptional processes for arbuscular mycorrhiza development.

Biological detection and analysis of mercury toxicity to alfalfa (Medicago sativa) plants.

Mercury has become one of the major causes of toxic metal pollution in agricultural lands. Accumulation of mercury by plants may disrupt many cellular functions and block growth and development. To assess mercury toxicity, we performed an experiment focusing on the responses of alfalfa (Medicago sativa) to Hg(2+)-induced oxidative stress.

Metabolic adaptations to mercury-induced oxidative stress in roots of Medicago sativa L.

Alfalfa (Medicago sativa) roots were treated with mercuric ions in a concentration- and time-dependent manner, and lipid peroxidation was studied biochemically as well as histochemically along with other physiological responses. Histochemical staining with Schiff's reagent and Evans blue revealed that the peroxidation of membrane lipids and loss of plasma membrane integrity in Hg-treated roots occurred in the meristem and the elongation zone. The histochemical observations were supported by the quantitative determinations of thiobarbituric acid reactive substances (TBARS).