Quantitative proteomic analysis of down syndrome biomarkers in maternal serum using isobaric tags for relative and absolute quantification (iTRAQ).

Prenatal diagnosis of Down syndrome (DS) is based on calculated risk involving maternal age, biochemical and ultrasonographic markers, and, more recently, cell-free DNA (cfDNA). The present study was designed to identify Down Syndrome biomarkers in maternal serum. We quantified the changes in maternal serum protein levels between 10 non-pregnant women, 10 pregnant women with healthy fetuses, and 10 pregnant women with DS fetuses using isobaric tags for relative and absolute quantification (iTRAQ). We subsequently conducted a Gene Ontology (GO) analysis. A total of 470 proteins were identified, 11 of which had significantly different serum levels between the DS fetus group and Healthy fetuses group. Our data shows the identified proteins may be relevant to DS and constitute potential DS biomarkers.

[Characteristics and phylogenetic analysis of mitochondrial genome in the gobies].

The vast number of species, small size and high variation of morphology make the morphological identification and classification of gobies very difficult. In this study, the complete mitochondrial genome (mitogenome) of 26 species of gobies was analyzed, aiming at accumulating the molecular information on the identification, classification and molecular evolution of gobies. The results showed that the gene composition and arrangement of mitogenome of gobies are similar to most vertebrates. Due to various degrees of repetitive sequences in the control region, the mitogenome of 26 gobies exhibits a great variation in length. The A+T content of the mitogenome is greater than 50% and the lowest frequency is for G among the four bases. Thirty-seven coding gene sequences were used to calculate the average Kimura 2-parameter genetic distance of 26 species of gobies. Acanthogobius hasta and A. ommaturus, Glossogobius olivaceus and G circumspectus were synonyms, respectively. By comparing the control region sequences of 26 gobies, the terminal associated sequences, central conserved sequence block and conserved sequence block were identified, respectively. Thirty-six coding gene sequences of 26 gobies were used to construct the phylogenetic tree and the results were different from the traditional morphological classification. The five subfamilies of Gobiidae were obviously evolved: Amblyopinae, Oxudercinae and Sicydiinae were clustered into a group and then formed a sister group with Gobionellinae; the fishes of Gobiinae had distant relationship with the four subfamilies and formed a group alone. Molecular clock analysis estimated that gobies probably originated in the late Eocene to Oligocene time and further evolved into modern characteristic gobies in the Miocene.

[Ion distribution, absorption and translocation characteristics of Alhagi sparsifolia in adaptation to saline habitat.] / 疏叶骆驼刺适应盐渍生境的离子分布、吸收和运输特征.

In order to explore the adaptive capacity of Alhagi sparsifolia to soil salinity (mild, mo-derate, severe saline soil), the distribution, adsorption and translocation characteristics of Na+, K+, Ca2+, Mg2+ in different organs of A. sparsifolia, which is a dominant native vegetation in southern edge of Tarim basin, were investigated. The results showed that when grown on a mild and moderate saline soil, Na+ distribution in different organs of A. sparsifolia followed the order of stem≈thorn>leaf>root; when grown on a severe saline soil, Na+ distribution followed leaf>stem≈thorn>root. The distribution of Ca2+ and Mg2+ followed leaf >thorn>stem>root. With the increase of soil salt level, Na+ content in different organs of A. sparsifolia increased, while K+ content in leave decreased; meanwhile the increasing soil salt level significantly decreased the K+/Na+ ratio in both root and leave, as well as the Ca2+/Na+ and Mg2+/Na+ ratios in all organs. The selective transportation coefficients for Ca2+-Na+ and Mg2+-Na+ followed order of stem-leaf>stem-thorn>root-stem under saline habitats. Based on the integrated analysis, in order to adapt to salinity habitat, A. sparsifolia could use multiple organs to accumulate Na+, depending on soil salt level. Na+ could accumulate in stem and thorn at a relative low level, but in leaves at high levels. Besides, Ca2+ and Mg2+ could be the inorganic osmotic adjustment substances for A. sparsifolia to adapt the saline environment.