Homology modeling and functional annotation of bubaline pregnancy associated glycoprotein 2

Background: Pregnancy associated glycoproteins form a diverse family of glycoproteins that are variably expressed at different stages of gestation. They are probably involved in immunosuppression of the dam against the feto- maternal placentome. The presence of the products of binucleate cells in maternal circulation has also been correlated with placentogenesis and placental re-modeling. The exact structure and function of the gene product is unknown due to limitations on obtaining purified pregnancy associated glycoprotein preparations. Results: Our study describes an in silico derived 3D model for bubaline pregnancy associated glycoprotein 2. Structure-activity features of the protein were characterized, and functional studies predict bubaline pregnancy associated glycoprotein 2 as an inducible, extra-cellular, non-essential, N-glycosylated, aspartic pro-endopeptidase that is involved in down-regulation of complement pathway and immunity during pregnancy. The protein is also predicted to be involved in nutritional processes, and apoptotic processes underlying fetal morphogenesis and re- modeling of feto-maternal tissues. Conclusion: The structural and functional annotation of buPAG2 shall allow the designing of mutants and inhibitors for dissection of the exact physiological role of the protein.     

Homology modeling and functional annotation of bubaline pregnancy associated glycoprotein 2

Background

Pregnancy associated glycoproteins form a diverse family of glycoproteins that are variably expressed at different stages of gestation. They are probably involved in immunosuppression of the dam against the feto-maternal placentome. The presence of the products of binucleate cells in maternal circulation has also been correlated with placentogenesis and placental re-modeling. The exact structure and function of the gene product is unknown due to limitations on obtaining purified pregnancy associated glycoprotein preparations.

Results

Our study describes an in silico derived 3D model for bubaline pregnancy associated glycoprotein 2. Structure-activity features of the protein were characterized, and functional studies predict bubaline pregnancy associated glycoprotein 2 as an inducible, extra-cellular, non-essential, N-glycosylated, aspartic pro-endopeptidase that is involved in down-regulation of complement pathway and immunity during pregnancy. The protein is also predicted to be involved in nutritional processes, and apoptotic processes underlying fetal morphogenesis and re-modeling of feto-maternal tissues.

Conclusion

The structural and functional annotation of buPAG2 shall allow the designing of mutants and inhibitors for dissection of the exact physiological role of the protein.     

Factors associated with colostrum quality in individual cows from dairy herds in the Waikato region of New Zealand

AIMS: To examine associations between various cow-level factors and quality of first-milking colostrum (measured as Brix), and to evaluate herd-level associations between vaccination against calf diarrhoea and colostrum quality, in cows from dairy herds in the Waikato region of New Zealand.

METHODS: A single colostrum sample was collected, by complete udder evacuation, from each of 20 cows from 29 dairy herds in the Waikato region of New Zealand during the 2016 spring calving period. Vaccination pre-partum with a calf diarrhoea vaccine was used in 15 herds. Each colostrum sample was tested using a digital Brix refractometer. The body condition score of each cow was recorded at the time of sample collection and farmers provided records of clinical mastitis and facial eczema from the previous 12 months, as well as the age and breed of cows. Associations between cow-level variables in non-vaccinated herds and Brix were examined using a multivariable linear mixed model and estimated marginal means obtained for different categories.

RESULTS: Mean Brix of 281 samples from cows in non-vaccinated herds was 18.7 (SD 0.26)%; 63/281 (22.4%) samples had Brix ≥22% and 152/281 (54.1%) had Brix ≥18%. Mean Brix of colostrum samples from cows aged ≥6 years (20.2 (95% CI=19.1–21.2)%) was higher than for samples from 2-year-old cows (18.6 (95% CI=17.3–19.9)%) (p=0.005). Colostrum that was collected at the first milking on the day of calving had higher Brix (20.0 (95% CI=19.1–20.9)%) than colostrum collected from cows that calved the previous day (17.5 (95% CI=16.5–18.4)%) (p<0.001). Mean Brix of colostrum samples from cows which produced ≥8?L (18.2 (95% CI=17.1–19.2)%) tended to be lower than from cows which produced <8?L first-milking colostrum (19.1 (95% CI=18.3–20.0)%) (p=0.08). Among vaccinating herds, 9/15 (60%) had ≥60% colostrum samples with Brix ≥18% compared with 4/14 (29%) of non-vaccinating herds (p=0.04).

CONCLUSIONS AND CLINICAL RELEVANCE: Colostrum quality, as measured by Brix, was associated with the total volume of first-milking colostrum, interval from calving to colostrum collection and cow age. Vaccination against calf diarrhoea was associated with a higher proportion of colostrum samples with adequate Brix. Careful selection of colostrum donor cows should ensure newborn calves are fed adequate quality colostrum which should be beneficial in preventing failure of passive transfer of IgG. Testing of colostrum from individual cows with a Brix refractometer is advocated for the selection of colostrum for feeding newborn calves.     

An empirical model for stomatal resistance of field-grown wheat

From concurrent data of stomatal conductance of sunlit leaves (C_i; mm s^?1), leaf water potential (ψ; m), and net radiation (R_n; W m^?2) we derive the empirical relationship:

$\text{C}{}_{\mathrm{l}}\text{=(0.986+0.025R}{}_{\mathrm{<mtext>n</mtext>}}\text{)}\text{1}\text{1+(}\text{ψ}\text{?230.8}\text{)}{}_{5.51}$

Stomatal conductances calculated using the above equation are compared with an independent data set. Canopy resistance derived from the above equation is used in a plant water balance equation to simulate diurnal evaporation fluxes for three days, and we compare the calculated fluxes with lysimeter observations for well-watered and water-stressed wheat. Canopy temperatures are additionally obtained from an energy balance equation and compared with infrared radiometer observations. Regression analysis of simulated and observed evaporation fluxes yields a correlation coefficient of 0.98 and a standard error of estimate of about 37 W m^?2; while for the canopy temperatures the correlation coefficient is 0.98 and the standard error of estimates 1.04°C. Variation of canopy net photosynthesis with insolation, and leaf area index are also simulated and compared with observations.     

A reexamination of the crop water stress index

Summary Hand-held infrared radiometers, developed during the past decade, have extended the measurement of plant canopy temperatures from individual leaves to entire plant canopies. Canopy temperatures are determined by the water status of the plants and by ambient meteorological conditions. The crop water stress index (CWSI) combines these factors and yields a measure of plant water stress. Two forms of the index have been proposed, an empirical approach as reported by Idso et al. (1981), and a theoretical approach reported by Jackson et al. (1981). Because it is simple and requires only three variables to be measured, the empirical approach has received much attention in the literature. It has, however received some criticism concerning its inability to account for temperature changes due to radiation and windspeed. The theoretical method is more complicated in that it requires these two additional variables to be measured, and the evaluation of an aerodynamic resistance, but it will account for differences in radiation and windspeed. This report reexamines the theoretical approach and proposes a method for estimating an aerodynamic resistance applicable to a plant canopy. A brief history of plant temperature measurements is given and the theoretical basis for the CWSI reviewed.     

Simulating sunflower canopy temperatures to infer root-zone soil water potential

A soil—plant—atmosphere model for sunflower (Helianthus annuus L.), together with clear sky weather data for several days, is used to study the relationship between canopy temperature and root-zone soil water potential. Considering the empirical dependence of stomatal resistance on insolation, air temperature and leaf water potential, a continuity equation for water flux in the soil—plant—atmosphere system is solved for the leaf water potential. The transpirational flux is calculated using Monteith's combination equation, while the canopy temperature is calculated from the energy balance equation. The simulation shows that, at high soil water potentials, canopy temperature is determined primarily by air and dew point temperatures. These results agree with an empirically derived linear regression equation relating canopy-air temperature differential to air vapor pressure deficit. The model predictions of leaf water potential are also in agreement with observations, indicating that measurements of canopy temperature together with a knowledge of air and dew point temperatures can provide a reliable estimate of the root-zone soil water potential.     

Exploration, collection and characterisation of Basmati rice germplasm in India

Eighty-eight long, slender, scented Basmati rice germplasms were collected from North India during an exploration mission. Morpho-agronomic characterisation of the accessions revealed a significant variability in leaf length, culm length, culm number and panicle length.     

Managing tragedies: understanding conflict over common pool resources

Conflicts over the management of common pool resources are not simply material. They also depend on the perceptions of the protagonists. Policy to improve management often assumes that problems are self-evident, but in fact careful and transparent consideration of the ways different stakeholders understand management problems is essential to effective dialogue.     

Synthesis and cytogenetic characterization of intergeneric hybrids of Diplotaxis siifolia with Brassica rapa and B. juncea

Intergeneric hybrids involving a wild crucifer, Diplotaxis siifolia (2n = 20; D^sD^s), and two crop Brassica species, namely Brassica rapa (2n = 20; AA) and B. juncea (2n = 36; AABB), were developed through sequential ovary/ovule culture. Hybridization was successful only when D. siifolia was used as the female parent, indicating unilateral cross incompatibility. Hybrids were intermediate between the parents for morphological characteristics but had low male as well as female fertility. Meiotic studies of hybrids revealed partial homoeology between D^s and A/B genomes.