Project description:Most of small RNA library construction methods are based on RNA ligases, which prefer to join the molecules (small RNAs and adapters) that can anneal to each other and form a ligase favoured structure. Different platforms for next generation sequencing use different adapter sequences, causing the cloning bias. Adapters with degenerated nucleotides at the ligating ends (High Definition, HD adapters) were developed to reduce the cloning bias. However, above 90% of the cloning products is adapter dimer when the current available commercial kits and their corresponding protocols are used. Here we adopted and further improved a method demonstrated in a publically available patent (http://www.google.com/patents/WO2011056866A2?cl=en). Using the improved method, we constructed the small RNA libraries by using the total RNA of chondrosarcoma cell line. The adapter dimer was significantly reduced. The small RNA sequences were also analysed. The small RNA libraries of cultured chondrosarcoma cell line were constructed by using an improved protocol where high-definition (HD) adapters were used.
Project description:Most of small RNA library construction methods are based on RNA ligases, which prefer to join the molecules (small RNAs and adapters) that can anneal to each other and form a ligase favoured structure. Different platforms for next generation sequencing use different adapter sequences, causing the cloning bias. Adapters with degenerated nucleotides at the ligating ends (High Definition, HD adapters) were developed to reduce the cloning bias. However, above 90% of the cloning products is adapter dimer when the current available commercial kits and their corresponding protocols are used. Here we adopted and further improved a method demonstrated in a publically available patent (http://www.google.com/patents/WO2011056866A2?cl=en). Using the improved method, we constructed the small RNA libraries by using the total RNA of Medicago truncatula leaf tissue. The adapter dimer was significantly reduced. The small RNA sequences were also analysed. The small RNA libraries of medicago truncatula leaves were constructed by using an improved protocol where high-definition (HD) adapters were used.
Project description:Most of small RNA library construction methods are based on RNA ligases, which prefer to join the molecules (small RNAs and adapters) that can anneal to each other and form a ligase favoured structure. Different platforms for next generation sequencing use different adapter sequences, causing the cloning bias. Adapters with degenerated nucleotides at the ligating ends (High Definition, HD adapters) were developed to reduce the cloning bias. However, above 90% of the cloning products is adapter dimer when the current available commercial kits and their corresponding protocols are used. Here we adopted and further improved a method demonstrated in a publically available patent (http://www.google.com/patents/WO2011056866A2?cl=en). Using the improved method, we constructed the small RNA libraries by using the total RNA of chondrosarcoma cell line. The adapter dimer was significantly reduced. The small RNA sequences were also analysed.
Project description:Most of small RNA library construction methods are based on RNA ligases, which prefer to join the molecules (small RNAs and adapters) that can anneal to each other and form a ligase favoured structure. Different platforms for next generation sequencing use different adapter sequences, causing the cloning bias. Adapters with degenerated nucleotides at the ligating ends (High Definition, HD adapters) were developed to reduce the cloning bias. However, above 90% of the cloning products is adapter dimer when the current available commercial kits and their corresponding protocols are used. Here we adopted and further improved a method demonstrated in a publically available patent (http://www.google.com/patents/WO2011056866A2?cl=en). Using the improved method, we constructed the small RNA libraries by using the total RNA of Medicago truncatula leaf tissue. The adapter dimer was significantly reduced. The small RNA sequences were also analysed.
Project description:One method of directional cloning of fragmented mRNA is based on single strand RNA ligation, for which ligation bias occurrs if the adapters have single sequences. The sequencing bias affects the mRNA quantification and subsequently the differential expression analysis. High definition (HD) adapters [Sorefan et al 2012, Xu et al 2015] can be used to diminish the cloning bias during library construction. HD adapters and standard illumina adapters were used to construct mRNA-seq libraries for a side by side comparison.
Project description:Study on sequencing biases introduced by library preparation step, namely by ligases. Comparison between standard Illumina protocol and improved High Definition (HD) protocol.
Project description:Study on sequencing biases introduced by library preparation step, namely by ligases. Comparison between standard Illumina protocol and improved High Definition (HD) protocol. Four replicates for N21 (21 random nucleotides), one replicate for N9 (9 random nucleotides), using either standard Illumina protocol or HD protocol
Project description:Small RNA libraries of three different mycovirus-infected A. fumigatus isolates were constructed by using Illumina high definition adapters. sRNAomes were analysed and putative virus-derived small RNAs were identified.
Project description:Multiple companies produce RecJ exonuclease and RNA dependent DNA polymerase for making cDNA. Our standard protocol was developed based on the enzymes from Epicenter (epicenter was recently bought by the Illumina company). As an alternative for the enzymes from EPicenter, we tested the RecJ exonuclease from NEB and Superperscript II from Invitrogen in sRNA library construction using HD adapters [Sorefan et al 2012, Xu et al 2015].
