3 research outputs found
Genetic diversity and population structure of locally adapted South African chicken lines: Implications for conservation.
In this study microsatellite markers were applied to investigate the genetic diversity and population structure of the six local chicken lines kept in the “Fowls for Africa” program, for better clarification of parameters for breed differentiation and genetic conservation of this valuable resource. The lines included the Black Australorp, Potchefstroom Koekoek, New Hampshire, Ovambo, Lebova- Venda and a Naked Neck line. Unbiased estimates for heterozygosity ranged from 50% in the Potchefstroom Koekoek to as high as 65% in the Naked Neck chickens. FIS values varied from as low as 0.16 for the Black Australorp line to as high as 0.35 for the Ovambo chickens. The FST values indicated moderate to high genetic differentiation between the Naked Neck and New Hampshire (0.11); Ovambo and Naked Neck lines (0.12), and Naked Neck and Lebowa- Venda (0.14). A total of 13% of the total genetic variation observed was between the chicken lines and 87% within the lines, supporting moderate genetic differentiation. Population structure was assessed using STRUCTURE where the Black Australorp was genetically best defined. Although six clusters for the different populations could be distinguished, the other lines were not as clearly defined, with individual birds tending to share more than one cluster. Results support a broad classification of these lines and further investigation of unique alleles is recommended for conservation of the lines within the program
Functional network analysis of genes differentially expressed during xylogenesis in soc1ful woody Arabidopsis plants
Many plant genes are known to be involved in the development of cambium and wood, but how the expres-
sion and functional interaction of these genes determine the unique biology of wood remains largely
unknown. We used the soc1ful loss of function mutant – the woodiest genotype known in the otherwise
herbaceous model plant Arabidopsis – to investigate the expression and interactions of genes involved in
secondary growth (wood formation). Detailed anatomical observations of the stem in combination with
mRNA sequencing were used to assess transcriptome remodeling during xylogenesis in wild-type and
woody soc1ful plants. To interpret the transcriptome changes, we constructed functional gene association
networks of differentially expressed genes using the STRING database. This analysis revealed functionally
enriched gene association hubs that are differentially expressed in herbaceous and woody tissues. In particular, we observed the differential expression of genes related to mechanical stress and jasmonate biosynthesis/signaling during wood formation in soc1ful plants that may be an effect of greater tension within
woody tissues. Our results suggest that habit shifts from herbaceous to woody life forms observed in many
angiosperm lineages could have evolved convergently by genetic changes that modulate the gene expres-
sion and interaction network, and thereby redeploy the conserved wood developmental program.Â
Plant sciencesNaturali
Bacterial profiling of Haemonchus contortus gut microbiome infecting Dohne Merino sheep in South Africa
A metagenomic approach was used to study the gut microbiome of Haemonchus contortus feld strains
and that of its predilection site, the abomasum of Dohne Merino sheep. The abomasum contents
and H. contortus were collected from 10 naturally infected Dohne Merino sheep. The H. contortus
specimens were classifed and sexually diferentiated using morphometric characters and was further
confrmed through molecular identifcation. We investigated diferences and similarities between the
bacterial composition of the adult male and female H. contortus gut microbiomes, which were both
dominated by bacteria from the Escherichia, Shigella, Vibrio and Halomonas genera. Major abundance
variations were identifed between the shared adult male and female H. contortus microbiomes.
The results also revealed that Succiniclasticum, Rikenellaceae RC9 gut group and Candidatus
Saccharimonas were the predominant genera in the Dohne Merino abomasum. This study provides
insight into the highly diverse bacterial composition of the H. contortus gut microbiome and the
Dohne Merino abomasum which needs to be studied further to explore the complex interactions of
diferent gastrointestinal nematode microbiomes with the host.http://www.nature.com/srep/index.htmlpm2022BiochemistryGenetic