Project description:BmN4 cells are cultured cells derived from Bombyx mori ovaries and widely used to study transposon silencing by PIWI-interacting RNAs (piRNAs). A high-accurate genome sequence of BmN4 cells is required to analyze the piRNA pathway using RNA-seq. The genome sequence of BmN4 cells was assembled using Pacific Biosciences (PacBio) HiFi and Oxford Nanopore technology Ultralong (ONT-UL) reads. Microscopic observation and image analysis showed that BmN4 cells were octoploid on average, and the number of chromosomes per cell was highly variable. We concluded the haplotype-resolved assembly of such a complex genome would be difficult; therefore, we assembled a consensus genome sequence. RNA-seq analysis of Siwi knockdown cells also revealed that Siwi-piRISC may target Countdown (Cd), an LTR retrotransposon. By comparing the consensus genome sequence with the reads, we identified differences between haplotypes, particulary structural variants, suggesting that some transposons, including Countdown, increased their copy number in BmN4 cells.
Project description:<p class='ql-align-justify'>Megasphaera hexanoica KCCM 43214T, isolated from cow rumen, is capable of producing medium-chain carboxylic acids such as n-caproate and n-caprylate. In this study, we present a high-quality genome assembly, along with intracellular metabolomic profiling and pangenomic analysis. Illumina sequencing generated 2.3 Mbp from 15,293,634 reads with a GC content of 49.5%, while PacBio HiFi sequencing produced 331.5 Mbp across 45,266 reads, with an average read length of 7,323 bp and a HiFi read N50 of 8,214 bp. Hybrid assembly of short and long reads resulted in a single 2.88 Mbp contig, containing 2,075-2,083 unique genes. A genome-scale metabolic model was constructed, to evaluate its metabolic capabilities under specific growth conditions. Intracellular metabolomic analysis of cells grown in fructose medium and lactate medium revealed key metabolic activities associated with chain elongation. Pangenomic analysis across nine annotated genomes identified 6,721 orthologous gene using OrthoMCL, emphasizing the genetic and functional diversity within the Megasphaera genus. This dataset offers valuable insights into the metabolism and biotechnological potential of M. hexanoica KCCM 43214T.</p>
