Genetic relationships and genome selection signatures between soybean cultivars from Brazil and United States after decades of breeding.

Soybean is one of the most important crops worldwide. Brazil and the United States (US) are the world's two biggest producers of this legume. The increase of publicly available DNA sequencing data as well as high-density genotyping data of multiple soybean germplasms has made it possible to understand the genetic relationships and identify genomics regions that underwent selection pressure during soy domestication and breeding.

Genetic Diversity and Selection Footprints in the Genome of Brazilian Soybean Cultivars.

Although Brazil is currently the largest soybean producer in the world, only a small number of studies have analyzed the genetic diversity of Brazilian soybean. These studies have shown the existence of a narrow genetic base. The objectives of this work were to analyze the population structure and genetic diversity, and to identify selection signatures in the genome of soybean germplasms from different companies in Brazil.

An integrated analysis of mRNA and sRNA transcriptional profiles in Coffea arabica L. roots: insights on nitrogen starvation responses.

Coffea arabica L. is an important agricultural commodity, accounting for 60% of traded coffee worldwide. Nitrogen (N) is a macronutrient that is usually limiting to plant yield; however, molecular mechanisms of plant acclimation to N limitation remain largely unknown in tropical woody crops.

Moving up, down, and everywhere: signaling of micronutrients in plants.

To cope with the variable availability of micronutrients, plants have evolved a complex set of physiological and developmental processes, which are under tight control of short-range and long-range signaling pathways. These signals act at the cellular and whole-plant scale to coordinate micronutrient homeostasis at the systemic and local level. Recently, several molecular components of the local and long-distance regulatory circuits as well as their putative positions in the signaling cascade have been identified.

CE of phytosiderophores and related metal species in plants.

Phytosiderophores (PS) and the closely related substance nicotianamine (NA) are key substances in metal uptake into graminaceous plants. Here, the CE separation of these substances and related metal species is demonstrated. In particular, the three PS 2'-deoxymugineic acid (DMA), mugineic acid (MA), and 3-epi-hydroxymugineic acid (epi-HMA), and NA, are separated using MES/Tris buffer at pH 7.

PIC1, an ancient permease in Arabidopsis chloroplasts, mediates iron transport.

In chloroplasts, the transition metals iron and copper play an essential role in photosynthetic electron transport and act as cofactors for superoxide dismutases. Iron is essential for chlorophyll biosynthesis, and ferritin clusters in plastids store iron during germination, development, and iron stress. Thus, plastidic homeostasis of transition metals, in particular of iron, is crucial for chloroplast as well as plant development.

Iron acquisition by phytosiderophores contributes to cadmium tolerance.

Based on the ability of phytosiderophores to chelate other heavy metals besides iron (Fe), phytosiderophores were suggested to prevent graminaceous plants from cadmium (Cd) toxicity. To assess interactions between Cd and phytosiderophore-mediated Fe acquisition, maize (Zea mays) plants were grown hydroponically under limiting Fe supply. Exposure to Cd decreased uptake rates of 59Fe(III)-phytosiderophores and enhanced the expression of the Fe-phytosiderophore transporter gene ZmYS1 in roots as well as the release of the phytosiderophore 2'-deoxymugineic acid (DMA) from roots under Fe deficiency.

Separation and identification of phytosiderophores and their metal complexes in plants by zwitterionic hydrophilic interaction liquid chromatography coupled to electrospray ionization mass spectrometry.

A sensitive method for the separation of different phytosiderophores (PS) of the mugineic acid (MA) family, and the candidate ligand for intracellular metal transport in plants nicotianamine (NA), and respective metal complexes in plants by zwitterionic hydrophilic interaction liquid chromatography (ZIC-HILIC) coupled to electrospray ionization mass spectrometry (ESI-MS) is described. Separation of mugineic acid, 2'-deoxymugineic acid (DMA), 3-epi-hydroxymugineic acid (epi-HMA), nicotianamine, Fe(III)-DMA, Fe(III)-NA, M(II)-DMA, and M(II)-NA complexes (M(II)=Zn(II), Cu(II), Ni(II), and Fe(II)), was achieved within 22 min on the ZIC-HILIC column by using a gradient elution with a mobile phase consisting of ammonium acetate and acetonitrile at pH 7.3, at a flow rate of 0.

AtIREG2 encodes a tonoplast transport protein involved in iron-dependent nickel detoxification in Arabidopsis thaliana roots.

Iron acquisition in Arabidopsis depends mainly on AtIRT1, a Fe2+ transporter in the plasma membrane of root cells. However, substrate specificity of AtIRT1 is low, leading to an excess accumulation of other transition metals in iron-deficient plants. In the present study we describe AtIREG2 as a nickel transporter at the vacuolar membrane that counterbalances the low substrate specificity of AtIRT1 and possibly other iron transport systems in iron-deficient root cells.