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Recent Submissions
Mainstreaming Research, Innovation and Technology Transfer and Commercialization for Sustainable Economies (MRIT-TCSE)
(Chuka University, 2024-10) 10th International Research Conference Proceedings
Exploring new frontiers in education, research and innovations for economic recovery
(Chuka University, 2023-10) 9th international Reasearch Conference Preceedings
Polysaccharides from Flammulina velutipes improve scopolamine-induced impairment of learning and memory of rats
(2015-08-12) Wenjian Yang a , Jie Yu a , Liyan Zhao b , Ning Ma a , Yong Fang a , Fei Pei a , Alfred Mugambi Mariga b,c , Qiuhui Hu a,b
Flammulina velutipes has been reported to be beneficial in learning and memory capabilities, but the mechanisms underlying this remain unclear. In this study, Morris water maze
and biochemical analyses of rat brain were used to evaluate the effects of F. velutipes polysaccharides (FVP) on scopolamine-induced learning and memory impairments. Results
suggested that FVP significantly decreased the escape latency and total swimming distance of rats in the hidden platform test and increased the numbers of platform crossing
and swimming distance of rats in the probe test. Biochemical examinations revealed that
FVP significantly elevates SOD and GSH-Px activities, as well as neurotransmitter levels. The
increased acetylcholine content owed to the increased acetylcholine acetyltransferase activity and decreased acetylcholinesterase activity. Moreover, learning and memory associated
signalling pathways were activated by FVP elevating the expression of connexin 36 and p-CaMK
II. These results conclusively proved that FVP is a potent agent against the progression of
cognitive impairment.
Targeted Sequencing Reveals Large-Scale Sequence Polymorphism in Maize Candidate Genes for Biomass Production and Composition
(KBBE-CornFed project, 2015-07-07) Moses M. Muraya, Thomas Schmutzer, Chris Ulpinnis , Uwe Scholz , Thomas Altmann
A major goal of maize genomic research is to identify sequence polymorphisms responsible
for phenotypic variation in traits of economic importance. Large-scale detection of sequence
variation is critical for linking genes, or genomic regions, to phenotypes. However, due to its
size and complexity, it remains expensive to generate whole genome sequences of sufficient coverage for divergent maize lines, even with access to next generation sequencing
(NGS) technology. Because methods involving reduction of genome complexity, such as
genotyping-by-sequencing (GBS), assess only a limited fraction of sequence variation, targeted sequencing of selected genomic loci offers an attractive alternative. We therefore
designed a sequence capture assay to target 29 Mb genomic regions and surveyed a total
of 4,648 genes possibly affecting biomass production in 21 diverse inbred maize lines (7
flints, 14 dents). Captured and enriched genomic DNA was sequenced using the 454 NGS
platform to 19.6-fold average depth coverage, and a broad evaluation of read alignment and
variant calling methods was performed to select optimal procedures for variant discovery.
Sequence alignment with the B73 reference and de novo assembly identified 383,145 putative single nucleotide polymorphisms (SNPs), of which 42,685 were non-synonymous alterations and 7,139 caused frameshifts. Presence/absence variation (PAV) of genes was also
detected. We found that substantial sequence variation exists among genomic regions targeted in this study, which was particularly evident within coding regions. This diversification
has the potential to broaden functional diversity and generate phenotypic variation that may
lead to new adaptations and the modification of important agronomic traits. Further, annotated SNPs identified here will serve as useful genetic tools and as candidates in searches
for phenotype-altering DNA variation. In summary, we demonstrated that sequencing of
captured DNA is a powerful approach for variant discovery in maize genes.
Targeted Sequencing Reveals Large-Scale Sequence Polymorphism in Maize Candidate Genes for Biomass Production and Composition
(KBBE-CornFed project, 2015-07-07) Moses M. Muraya, Thomas Schmutzer, Chris Ulpinnis, Uwe Scholz, Thomas Altmann
A major goal of maize genomic research is to identify sequence polymorphisms responsible for phenotypic variation in traits of economic importance. Large-scale detection of sequence variation is critical for linking genes, or genomic regions, to phenotypes. However, due to its size and complexity, it remains expensive to generate whole genome sequences of suffi- cient coverage for divergent maize lines, even with access to next generation sequencing (NGS) technology. Because methods involving reduction of genome complexity, such as genotyping-by-sequencing (GBS), assess only a limited fraction of sequence variation, tar- geted sequencing of selected genomic loci offers an attractive alternative. We therefore designed a sequence capture assay to target 29 Mb genomic regions and surveyed a total of 4,648 genes possibly affecting biomass production in 21 diverse inbred maize lines (7 flints, 14 dents). Captured and enriched genomic DNA was sequenced using the 454 NGS platform to 19.6-fold average depth coverage, and a broad evaluation of read alignment and variant calling methods was performed to select optimal procedures for variant discovery.
Sequence alignment with the B73 reference and de novo assembly identified 383,145 puta- tive single nucleotide polymorphisms (SNPs), of which 42,685 were non-synonymous alter- ations and 7,139 caused frameshifts. Presence/absence variation (PAV) of genes was also detected. We found that substantial sequence variation exists among genomic regions tar- geted in this study, which was particularly evident within coding regions. This diversification has the potential to broaden functional diversity and generate phenotypic variation that may lead to new adaptations and the modification of important agronomic traits. Further, anno- tated SNPs identified here will serve as useful genetic tools and as candidates in searches for phenotype-altering DNA variation. In summary, we demonstrated that sequencing of captured DNA is a powerful approach for variant discovery in maize genes