Biology subjects

Baten, A.

Publications and source records attributed to Baten, A..

7 recordsLinked to original sources

bioRxiv2021

Genome sequence of Pseudopithomyces chartarum, causal agent of facial eczema (pithomycotoxicosis) in ruminants, and identification of the putative sporidesmin toxin gene cluster

Facial eczema (FE) in grazing ruminants is a debilitating liver syndrome induced by ingestion of sporidesmin, a toxin belonging to the epipolythiodioxopiperazine class of compounds. Sporidesmin is produced in spores of the fungus Pseudopithomyces chartarum, a microbe which colonises leaf litter in pastures. New Zealand has a high occurrence of FE in comparison to other countries as animals are fed predominantly on ryegrass, a species that supports high levels of Pse. chartarum spores. The climate is also particularly conducive for Pse. chartarum growth. Here, we present the genome of Pse. chartarum and identify the putative sporidesmin gene cluster. The Pse. chartarum genome was sequenced using single molecule real-time sequencing (PacBio) and gene models identified. Loci containing genes with homology to the aspirochlorine, sirodesmin PL and gliotoxin cluster genes of Aspergillus oryzae, Leptosphaeria maculans and Aspergillus fumigatus, respectively, were identified by tBLASTn. We identified and annotated an epipolythiodioxopiperazine cluster at a single locus with all the functionality required to synthesise sporidesmin. HighlightsO_LIThe whole genome of Pseudopithomyces chartarum has been sequenced and assembled. C_LIO_LIThe genome is 39.13 Mb, 99% complete, and contains 11,711 protein coding genes. C_LIO_LIA putative sporidesmin A toxin (cause of facial eczema) gene cluster is described. C_LIO_LIThe genomes of Pse. chartarum and the Leptosphaerulina chartarum teleomorph differ. C_LIO_LIComparative genomics is required to further resolve the Pseudopithomyces clade. C_LI

genomics↗

bioRxiv2020

Complete mitochondrial genome sequence of Bos frontalis (Gayal) from Bangladesh

The Gayal is a large-sized endangered semi-domesticated bovine species belonging to the family Bovidae, tribe Bovini, group Bovina, genus Bos, and species Bos frontalis. It is also called the Mithan or Mithun. Mitochondrial genome is considered as an important tool for species identification and monitoring the populations of conservation concern and therefore it becomes an obligation to sequence the mitochondrial genome of Bagladeshi gayal. We want to identify some important genes related to a particular trait such as those associated with adaptation, muscle strength, or prolificacy. The data will help explore evolutionary relationships with closely related species. The mitogenome of Bos frontalis is 16,347 bp in length and nucleotide composition is AT-based (60.21%), contains 37 genes including 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a control region.

bioinformatics↗

bioRxiv2020

Chromosome-scale assembly and annotation of the macadamia genome(Macadamia integrifolia HAES 741)

Macadamia integrifolia is a representative of the large basal eudicot family Proteaceae and the main progenitor species of the Australian native nut crop macadamia. Since its commercialisation in Hawaii fewer than 100 years ago, global production has expanded rapidly. However, genomic resources are limited in comparison to other horticultural crops. The first draft assembly of M. integrifolia had good coverage of the functional gene space but its high fragmentation has restricted its use in comparative genomics and association studies. Here we have generated an improved assembly of cultivar HAES 741 (4,094 scaffolds, 745 Mb, N50 413 kb) using a combination of Illumina paired and PacBio long read sequences. Scaffolds were anchored to 14 pseudo-chromosomes using seven genetic linkage maps. This assembly has improved contiguity and coverage, with >120 Gb of additional sequence. Following annotation, 34,274 protein-coding genes were predicted, representing 92% of the expected gene content. Our results indicate that the macadamia genome is repetitive and heterozygous. The total repeat content was 55% and genome-wide heterozygosity, estimated by read mapping, was 0.98% or one SNP per 102 bp. This is the first chromosome-scale genome assembly for macadamia and the Proteaceae. It is expected to be a valuable resource for breeding, gene discovery, conservation and evolutionary genomics.

genomics↗

bioRxiv2019

Abundant expression of maternal siRNAs is a conserved feature of seed development

Small RNAs are abundant in plant reproductive tissues, especially 24-nt short interfering (si)RNAs. Most 24-nt siRNAs are dependent on RNA Pol IV and RDR2, and establish DNA methylation at thousands of genomic loci in a process called RNA-directed DNA methylation (RdDM). In Brassica rapa, RdDM is required in the maternal sporophyte for successful seed development. Here we demonstrate that a small number of siRNA loci account for over 90% of siRNA expression during B. rapa seed development. These loci exhibit unique characteristics with regard to their copy number and association with genomic features, but they resemble canonical 24-nt siRNA loci in their dependence on RNA Pol IV/RDR2 and role in RdDM. These loci are expressed in ovules before fertilization and in the seed coat, embryo, and endosperm following fertilization. We observed a similar pattern of 24-nt siRNA expression in diverse angiosperms despite rapid sequence evolution at siren loci. In the endosperm, siren siRNAs show a marked maternal bias, and siren expression in maternal sporophytic tissues is required for siren siRNA accumulation. Together these results demonstrate that seed development occurs under the influence of abundant maternal siRNAs that might be transported to, and function in, filial tissues. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=128 SRC="FIGDIR/small/866806v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@68de55org.highwire.dtl.DTLVardef@dca8eaorg.highwire.dtl.DTLVardef@d5d489org.highwire.dtl.DTLVardef@74824a_HPS_FORMAT_FIGEXP M_FIG C_FIG

plant biology↗

bioRxiv2019

Common breast cancer risk loci predispose to distinct tumor subtypes

BackgroundGenome-wide association studies (GWAS) have identified multiple common breast cancer susceptibility variants. Many of these variants have differential associations by estrogen receptor (ER), but how these variants relate with other tumor features and intrinsic molecular subtypes is unclear. MethodsAmong 106,571 invasive breast cancer cases and 95,762 controls of European ancestry with data on 173 breast cancer variants identified in previous GWAS, we used novel two-stage polytomous logistic regression models to evaluate variants in relation to multiple tumor features (ER, progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and grade) adjusting for each other, and to intrinsic-like subtypes. ResultsEighty-five of 173 variants were associated with at least one tumor feature (false discovery rate <5%), most commonly ER and grade, followed by PR and HER2. Models for intrinsic-like subtypes found nearly all of these variants (83 of 85) associated at P<0.05 with risk for at least one luminal-like subtype, and approximately half (41 of 85) of the variants were associated with risk of at least one non-luminal subtype, including 32 variants associated with triple-negative (TN) disease. Ten variants were associated with risk of all subtypes in different magnitude. Five variants were associated with risk of luminal A-like and TN subtypes in opposite directions. ConclusionThis report demonstrates a high level of complexity in the etiology heterogeneity of breast cancer susceptibility variants and can inform investigations of subtype-specific risk prediction.

genetics↗

bioRxiv2019

First report of reference guided genome assembly of Black Bengal goat (Capra hircus)

ObjectivesBlack Bengal goat (Capra hircus), a member of the Bovidae family with the unique traits of high prolificacy, skin quality and low demand for food is the most socioeconomically significant goat breed in Bangladesh. Furthermore, the aptitude of adaptation and disease resistance capacity of it is highly notable which makes its whole genome information an area of research interest.\n\nData descriptionThe genomic DNA of local (Chittagong, Bangladesh) healthy Black Bengal goat (Capra hircus) was extracted and then sequenced. The de novo assembly and structural annotations are being presented here. Sequencing was done using Illumina sequencing platform and the draft genome assembled is about 3.04 Gb. 26458 Genes were annotated using Maker gene annotations tool which predicted BUSCO Gene models. Universal Single Copy Orthologs refer 82.5% completeness of the assembled genome.

genomics↗

bioRxiv2017

Maternal RNA-directed DNA methylation is required for seed development in Brassica rapa

Some organisms deploy small RNAs from accessory cells to maintain genome integrity in the zygote, a mechanism that has been proposed but not demonstrated in plants. Here we show that maternal mutations in the Pol IV-dependent small RNA pathway cause abortion of developing seeds in Brassica rapa. Surprisingly, small RNA production is required in maternal somatic tissues, but not in maternal gametes or the developing zygote. We propose that parental influence over zygotic genomes is a common strategy in eukaryotes and that outbreeding species such as B. rapa are key to understanding the role of small RNAs during reproduction.

plant biology↗