Isolation of two highly active soybean (<Emphasis Type="Italic">Glycine max</Emphasis> (L.) Merr.) promoters and their characterization using a new automated image collection and analysis system

A novel automated image collection and analysis system was used to compare two new soybean (Glycine max (L.) Merr.) promoters with the cauliflower mosaic virus 35S (CaMV35S) promoter, which was used as an expression standard. For expression comparisons, various permutations of a soybean polyubiquitin (Gmubi) promoter, a soybean heat shock protein 90-like (GmHSP90L) promoter and the CaMV35S promoter were placed upstream of a green fluorescent protein (gfp) gene. DNA constructs were introduced via particle bombardment into excised cotyledons of germinating lima bean (Phaseolus lunatus L.) seeds, which were arranged in Petri dishes for automated image capture and image analysis. The automated system allowed monitoring and quantification of gfp gene expression in the same piece of tissue over time. The Gmubi promoter, with its intronic region intact, showed the highest expression that was over five times stronger than the CaMV35S promoter. When an intronic region was removed from the Gmubi promoter, GFP expression was reduced, but was still over two times greater than with the CaMV35S promoter. The full-length soybean GmHSP90L promoter was four times stronger than the CaMV35S promoter. Truncation of the GmHSP90L promoter resulted in stepwise decreases in promoter strength, which appear to correspond to removal of regulatory elements. Automated image capture and analysis allowed the rapid and efficient evaluation of these new promoters. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Both inflammatory and regulatory cytokine responses to malaria are blunted with increasing age in highly exposed children

Background

Young children are at greatest risk for malaria-associated morbidity and mortality. The immune response of young children differs in fundamental ways from that of adults, and these differences likely contribute to the increased susceptibility of children to severe malaria and to their delayed development of immunity. Elevated levels of pro-inflammatory cytokines and chemokines in the peripheral blood during acute infection contribute to the control of parasitaemia, but are also responsible for much of the immunopathology seen during symptomatic disease. Clinical immunity to malaria may depend upon the ability to regulate these pro-inflammatory responses, possibly through mechanisms of immunologic tolerance. In order to explore the effect of age on the immune response to malaria and the development of clinical immunity, cytokines and chemokines were measured in the plasma of children at day 0 of an acute malaria episode and during convalescence.

Results

Younger children presenting with acute malaria exhibited much higher levels of TNF, IL2, and IL6, as well as increased Th1 associated chemokines IP10, MIG, and MCP1, compared to older children with acute malaria. Additionally, the regulatory cytokines IL10 and TNFRI were dramatically elevated in younger children compared to older children during acute infection, indicating that regulatory as well as pro-inflammatory cytokine responses are dampened in later childhood.

Conclusions

Together these data suggest that there is a profound blunting of the cytokine and chemokine response to malaria among older children residing in endemic settings, which may be due to repeated malaria exposure, intrinsic age-based differences in the immune response, or both.

     

Genetic variation in South Indian castes: evidence from Y-chromosome, mitochondrial, and autosomal polymorphisms

Background

Major population movements, social structure, and caste endogamy have influenced the genetic structure of Indian populations. An understanding of these influences is increasingly important as gene mapping and case-control studies are initiated in South Indian populations.

Results

We report new data on 155 individuals from four Tamil caste populations of South India and perform comparative analyses with caste populations from the neighboring state of Andhra Pradesh. Genetic differentiation among Tamil castes is low (R_ST = 0.96% for 45 autosomal short tandem repeat (STR) markers), reflecting a largely common origin. Nonetheless, caste- and continent-specific patterns are evident. For 32 lineage-defining Y-chromosome SNPs, Tamil castes show higher affinity to Europeans than to eastern Asians, and genetic distance estimates to the Europeans are ordered by caste rank. For 32 lineage-defining mitochondrial SNPs and hypervariable sequence (HVS) 1, Tamil castes have higher affinity to eastern Asians than to Europeans. For 45 autosomal STRs, upper and middle rank castes show higher affinity to Europeans than do lower rank castes from either Tamil Nadu or Andhra Pradesh. Local between-caste variation (Tamil Nadu R_ST = 0.96%, Andhra Pradesh R_ST = 0.77%) exceeds the estimate of variation between these geographically separated groups (R_ST = 0.12%). Low, but statistically significant, correlations between caste rank distance and genetic distance are demonstrated for Tamil castes using Y-chromosome, mtDNA, and autosomal data.

Conclusion

Genetic data from Y-chromosome, mtDNA, and autosomal STRs are in accord with historical accounts of northwest to southeast population movements in India. The influence of ancient and historical population movements and caste social structure can be detected and replicated in South Indian caste populations from two different geographic regions.     

Behavior and adrenal physiology of Magellanic penguins (Spheniscus magellanicus) serving as ambassador animals

Ambassador animals are part of many zoo programs, but studies assessing their impact on these animals are relatively rare. This study validated an excrement glucocorticoid metabolite (GCM) assay for Magellanic penguins and used GCM measures in conjunction with behavioral observations to evaluate individual responses to participation in an ambassador animal program. Excrement samples and behavioral observations were collected daily from each bird during two phases, 1 week during which it participated in a twice-daily ambassador program and 1 week in which it did not. We found no differences in GCMs between phases or in comparisons between penguins with 5 or 10 years of program experience. GCM also did not show significant individual variation and did not increase over time during the program phase. There were no significant correlations between bird experience and behavior frequencies, nor GCM concentrations and behavior, across birds. We observed significant positive correlations between the penguins' engagement with novel objects during programs and their unguided approach to guests. Our results suggest that there is no adverse physiological effect of program participation on these penguins, that behavioral and physiological responses may be decoupled, and that choice and control can increase desired behaviors behavior during ambassador programs.