Interspecific differences in root architecture among maize and triticale genotypes grown under drought,waterlogging and soil compaction

Environmental stresses (soil compaction, drought, waterlogging) cause changes in plants’ root system structure, also affecting the growth of above-ground parts. The aim of this study was to estimate phenotypic variation among maize and triticale genotypes in root penetration ability through petrolatum-wax-layer (RPA). Also, the effect of shortage or excess of soil water on dry matter of shoots and roots and morphological changes in root system structure in sensitive and resistant maize and triticale genotypes grown in low or high soil compaction level was evaluated. To estimate RPA index, the petrolatum-wax-layer method (PWL) was used. The strength of three petrolatum-wax concentrations 60, 50 and 40 % was 0.52, 1.07 and 1.58 MPa, respectively. High coefficients of variation (CV) were observed in 0.52 and 1.07 MPa and for maize were 19.2 and 21.7 %, and for triticale, 12.5 and 18.3 %, respectively. The data indicate that the use of PWL technique is an effective screening method, and makes it possible to divide the genotypes into resistant and sensitive groups. The second part of this study investigated a multistress effect of soil compaction combined with drought or waterlogging on root and shoot growth and morphological changes in root system structure of maize and triticale genotypes differing in susceptibility to environmental stresses. Seedlings were grown for 4 weeks in root-boxes under conditions of low (LSC 1.1 g cm^?3) or severe (SSC 1.6 g cm^?3) soil compaction. Drought or waterlogging stresses were applied for 2 weeks from 14th to 28th day. In comparison to LSC treatment, in SSC treatment the decrease in dry matter of shoots and roots was greater for sensitive genotypes of maize and triticale (Ancora, CHD-147). Soil drought or waterlogging caused greater decrease of dry matter of shoots and roots in seedlings grown in SSC in comparison to LSC. The root penetration index (RPI) was estimated as a ratio of root dry matter in 15–40 cm root-box layer to total root dry matter. On the basis of RPI it was possible to group the genotypes according to their ability to distribute roots in soil profile. In comparison to LSC, SSC exerted a strong influence on the length of seminal and seminal adventitious roots, as well as the number and length of L- and S-type lateral roots developed on seminal and nodal roots. In both species the restriction effect of soil compaction on number and length of roots was more severe in sensitive (Ankora, CHD-147) than in resistant (Tina, CHD-247) genotypes. The restriction in roots propagation was greater in triticale than in maize. Exposure to drought or waterlogging in the case of genotypes grown in LSC and SSC treatments caused a decrease in number and length of particular components of root system structure. In both species the decrease of root number and length in plants grown under waterlogging was greater than under drought. The observed changes in root system were greater in sensitive (Ankora, CHD147) than in resistant (Tina, CHD-247) genotypes. Statistically significant correlations were found between RPA and RPI and also between these indexes and soil compaction, drought and waterlogging susceptibility indexes. This indicates that genotypes resistant to soil compaction were resistant to drought or waterlogging and also that genotypes resistant to drought were resistant to waterlogging.     

Spatial patterns in brown bear Ursus arctos diet: the role of geographical and environmental factors

• 1 We reviewed worldwide spatial patterns in the food habits of the brown bear Ursus arctos in relation to geographical (latitude, longitude, altitude) and environmental (temperature, snow cover depth and duration, precipitation, primary productivity) variables.
• 2 We collected data from 28 studies on brown bear diet based on faecal analysis, covering the entire geographical range of this widely distributed large carnivore. We analysed separately four data sets based on different methods of diet assessment.
• 3 Temperature and snow conditions were the most important factors determining the composition of brown bear diet. Populations in locations with deeper snow cover, lower temperatures and lower productivity consumed significantly more vertebrates, fewer invertebrates and less mast. Trophic diversity was positively correlated with temperature, precipitation and productivity but negatively correlated with the duration of snow cover and snow depth. Brown bear populations from temperate forest biomes had the most diverse diet. In general, environmental factors were more explicative of diet than geographical variables.
• 4 Dietary spatial patterns were best revealed by the relative biomass and energy content methods of diet analysis, whereas the frequency of occurrence and relative biomass methods were most appropriate for investigating variation in trophic diversity.
• 5 Spatial variation in brown bear diet is the result of environmental conditions, especially climatic factors, which affect the nutritional and energetic requirements of brown bears as well as the local availability of food. The trade‐off between food availability on the one hand, and nutritional and energetic requirements on the other hand, determines brown bear foraging decisions. In hibernating species such as the brown bear, winter severity seems to play a role in determining foraging strategies. Large‐scale reviews of food habits should be based on several measures of diet composition, with special attention to those methods reflecting the energetic value of food.

     

Androgens and FSH affect androgen receptor and aromatase distribution in the porcine ovary

In the present study the authors investigated whether androgens could interact with FSH to induce aromatase and androgen receptor expression in porcine granulosa cells. Dissected whole porcine follicles (small, medium, and large) were incubated for 8 hours in M199 medium supplemented with testosterone (10(-7) M), FSH (100 ng/ml) or both those hormones. After incubation, the follicles were fixed and immunostained to visualise androgen receptor and aromatase. In cultures of granulosa cells isolated from small and large follicles, oestrogen secretion was measured by appropriate RIA. Incubation of follicles with testosterone and FSH increased aromatase immunoreactivity in preantral and early antral (i.e. small) follicles. The immunostaining for androgen receptor was slightly higher in medium follicles, while such hormonal stimulation had no effect on small and large follicles. Moreover, granulosa cells isolated from small follicles cultured with both testosterone and FSH produced more estradiol than control cultures (40 pg vs. 100 pg/10(5) cells). The level was relatively close to that obtained in the culture of control granulosa cells isolated from large preovulatory follicles (105 pg/10(5) cells). These results indicate that testosterone acts synergistically with FSH to increase aromatase expression in the small porcine follicles.     

Using biosorption to enrich the biomass of <Emphasis Type="Italic">Chlorella vulgaris </Emphasis>with microelements to be used as mineral feed supplement

The paper discusses biosorption of Cr(III), Cu(II), Mn(II), Zn(II) and Co(II) to the biomass of Chlorella vulgaris, to produce a biologically bound, concentrated form of microelements. The kinetics of biosorption was described with a pseudo-second order equation and equilibrium with the Langmuir isotherm. The mechanism of biosorption was identified as cation-exchange with alkaline metals. Cation-exchange capacity was evaluated as 4.07 meq g⁻¹. The effect of operation conditions, pH and temperature, on biosorption performance was investigated and the best operation conditions for biosorption were selected (pH 5, temperature 25 °C). The maximum sorption capacity of microelements was determined in single-metal system at pH 5 and 25 °C: Zn(II) 3.30 meq g⁻¹, Cu(II) 1.77 meq g⁻¹, Co(II) 1.75 meq g⁻¹, Cr(III) 1.74 meq g⁻¹, Mn(II) 0.764 meq g⁻¹. Biosorption experiments were also carried out in multi-metal system. The biomass of C. vulgaris enriched with microelements via the process of biosorption in both single- and multi-metal system was discussed in terms of preparation of feed supplement for laying hens and piglets. The experiments showed that 1 kg of conventional feed for laying hens can be supplemented with 0.20 g of the biomass enriched with microelements and for piglets with 0.15 g of the preparation.     

Site-specific Phosphorylation of Kindlin-3 Protein Regulates Its Capacity to Control Cellular Responses Mediated by Integrin αIIbβ3

The contributions of integrins to cellular responses depend upon their activation, which is regulated by binding of proteins to their cytoplasmic tails. Kindlins are integrin cytoplasmic tail binding partners and are essential for optimal integrin activation, and kindlin-3 fulfills this role in hematopoietic cells. Here, we used human platelets and human erythroleukemia (HEL) cells, which express integrin α_IIbβ₃, to investigate whether phosphorylation of kindlin-3 regulates integrin activation. When HEL cells were stimulated with thrombopoietin or phorbol 12-myristate 13-acetate (PMA), α_IIbβ₃ became activated as evidenced by binding of an activation-specific monoclonal antibody and soluble fibrinogen, adherence and spreading on fibrinogen, colocalization of β₃ integrin and kindlin-3 in focal adhesions, and enhanced β₃ integrin-kindlin-3 association in immunoprecipitates. Kindlin-3 knockdown impaired adhesion and spreading on fibrinogen. Stimulation of HEL cells with agonists significantly increased kindlin-3 phosphorylation as detected by mass spectrometric sequencing. Thr⁴⁸² or Ser⁴⁸⁴ was identified as a phosphorylation site, which resides in a sequence not conserved in kindlin-1 or kindlin-2. These same residues were phosphorylated in kindlin-3 when platelets were stimulated with thrombin. When expressed in HEL cells, T482A/S484A kindlin-3 decreased soluble ligand binding and cell spreading on fibrinogen compared with wild-type kindlin-3. A membrane-permeable peptide containing residues 476–485 of kindlin-3 was introduced into HEL cells and platelets; adhesion and spreading of both cell types were blunted compared with a scrambled control peptide. These data identify a role of kindlin-3 phosphorylation in integrin β₃ activation and provide a basis for functional differences between kindlin-3 and the two other kindlin paralogs.     

The influence of a seabird colony on abundance and species composition of water bears (Tardigrada) in Hornsund (Spitsbergen,Arctic)

Seabirds in the Arctic are known to link marine and terrestrial ecosystems. They feed in the sea and breed on land, where they deposit enormous amounts of guano. Soil in the vicinity of seabird colonies is much more enriched with nutrients as compared to areas beyond their impact, which positively affects primary and secondary production. Water bears (Tardigrada) are microinvertebrates which constitute a permanent and ubiquitous faunal component of polar regions. Here, we tested the influence of seabird guano on Tardigrada communities; we established two transects in Hornsund (SW Spitsbergen): (1) SEABIRD where little auks (Alle alle) nested, and (2) CONTROL, an area without a little auk colony. In total, we collected 160 moss, lichen and mixed (moss/lichen) samples from those areas. In total, we found 1990 specimens belonging to 32 taxa (25 identified to species level). The average density of water bears was higher in the SEABIRD transect (9.31 ind g^?1), where mosses predominated over lichens, in comparison with the CONTROL transect (5.83 ind g^?1), where more lichens occurred. Thus, ornithogenic enrichment of soil and locally facilitated development of mosses over lichens might be important factors responsible for the increase in invertebrate abundance. According to canonical correspondence analysis, the little auk colony effect explained 13.2 % of the tardigrade species composition, and this factor appeared to be more important than the vegetation type itself. Four taxa, i.e. Isohypsibius cf. reticulatus, Microhypsibius bertolanii, Minibiotus cf. formosus and Ramazzottius cf. rupeus, have been recorded in the Svalbard archipelago for the first time.     

Differential expression of Snail1 transcription factor and Snail1-related genes in alveolar and embryonal rhabdomyosarcoma subtypes

Rhabdomyosarcoma (RMS) represents the most common sarcoma of soft tissue among children. Two main RMS subtypes are alveolar (ARMS) and embryonal (ERMS). The major goal of this study was to find differentially expressed genes between RMS subtypes that could explain higher metastatic potential in ARMS and would be useful for the differential diagnosis. Using RQ-PCR analysis we compared expression of Snail1 and Snail-related genes among 7 ARMS and 8 ERMS patients' samples obtained from the primary tumors and among 2 alveolar and 2 embryonal cell lines. Our results show that Snail1 is highly expressed both in ARMS patients' samples and the alveolar cell lines. We also found that the expression of E-Cadherin was downregulated and the expression of Matrix Metalloproteinases 2 and 9 (MMP-2 and MMP-9) was upregulated in ARMS. We assume that, as in many tumors, also in RMS Snail1 acts as a regulator for pathways known for their role in cells' metastasis and that Snail1 activity results in increased MMPs and decreased E-Cadherin expression. Our findings may explain higher ARMS aggressiveness. Moreover, we suggest that further studies should be performed to verify if Snail1 can be considered as a potential target for ARMS therapy.     

MKS and NPHP modules cooperate to establish basal body/transition zone membrane associations and ciliary gate function during ciliogenesis

Meckel-Gruber syndrome (MKS), nephronophthisis (NPHP), and related ciliopathies present with overlapping phenotypes and display considerable allelism between at least twelve different genes of largely unexplained function. We demonstrate that the conserved C. elegans B9 domain (MKS-1, MKSR-1, and MKSR-2), MKS-3/TMEM67, MKS-5/RPGRIP1L, MKS-6/CC2D2A, NPHP-1, and NPHP-4 proteins exhibit essential, collective functions at the transition zone (TZ), an underappreciated region at the base of all cilia characterized by Y-shaped assemblages that link axoneme microtubules to surrounding membrane. These TZ proteins functionally interact as members of two distinct modules, which together contribute to an early ciliogenic event. Specifically, MKS/MKSR/NPHP proteins establish basal body/TZ membrane attachments before or coinciding with intraflagellar transport-dependent axoneme extension and subsequently restrict accumulation of nonciliary components within the ciliary compartment. Together, our findings uncover a unified role for eight TZ-localized proteins in basal body anchoring and establishing a ciliary gate during ciliogenesis, and suggest that disrupting ciliary gate function contributes to phenotypic features of the MKS/NPHP disease spectrum.