Biomedical subjects

Douglas B Rusch

Publications and source records attributed to Douglas B Rusch.

6 recordsLinked to original sources

PubMed2026

Mast Cells Selectively Deliver Extracellular Vesicle-Encapsulated mRNA to Colorectal Cancer Cells.

Mast cells (MCs), a type of granulocytic immune cell, exert contrasting effects on tumorigenesis. The anti- or pro-tumorigenic activity of MCs depends on the cancer type, tumor microenvironment, and MC localization within the tumor. Consequently, their role remains controversial and poorly understood across multiple cancer types, including colorectal cancer (CRC). Most proposed mechanisms underlying MC activity in CRC have focused on MC secretion of biological factors. In this study, we demonstrated that MCs transfer extracellular vesicles containing mRNAs and proteins to CRC cells. This process occurs through a tightly regulated mechanism that requires direct cell-cell contact, calcium signaling, and integrin-mediated interactions. Such requirements resemble aspects of immunological synapses observed between lymphocytes and cancer cells. The novel mode of intercellular communication between MCs and cancer cells described here may help refine our understanding of MC functions in cancer biology.

Mast Cells↗

PubMed2026

The role of estrogen receptors and house dust mite-induced DNA methylation in a mouse model.

Asthma is a chronic respiratory disease affecting over 230 million people worldwide, with higher prevalence in women. Environmental allergens such as house dust mite (HDM) trigger airway inflammation and hyperresponsiveness (AHR), yet the epigenetic mechanisms underlying these responses remain poorly understood. Furthermore, the role of estrogen receptors in the context of asthma is understudied. We aimed to investigate whether estrogen receptor-specific DNA methylation contributes to HDM-induced airway remodeling and hyperresponsiveness. Male and female C57BL/6J wild-type mice and estrogen receptor α and β knockout mice (Esr1-/- and Esr2-/-) were exposed to HDM or phosphate-buffered saline for 5 wk. DNA methylation and RNA sequencing data were obtained from snap-frozen whole lung tissues. HDM exposure resulted in widespread differential methylation of genes associated with inflammation and AHR, including Itgal, Tmem267, Rap1b, Bmf, Mid1, Fgd1, Ddx4, Comtd1, Filip1l, Grb10, and Chst7. Notably, the absence of estrogen receptor β (in Esr2-/- mice) produced the most pronounced methylation patterns, particularly in females. Pathway enrichment analysis revealed asthma-relevant processes such as extracellular matrix remodeling, leukocyte adhesion and migration, airway smooth muscle contraction, and inflammatory signaling. Integration of methylation and gene expression data confirmed significant correlations (P < 0.05) for Itgal, Rap1b, and Tmem267, and a marginal correlation for Chst7 (P < 0.1), implicating these genes in allergic asthma pathogenesis. Our findings demonstrate that HDM exposure induces sex-specific epigenetic changes mediated by estrogen receptor status, highlighting a potential mechanism for increased asthma susceptibility in women. These results can inform estrogen receptor-targeted treatment strategies for allergic airway diseases.NEW & NOTEWORTHY Understanding estrogen receptor-mediated epigenetic regulation provides a foundation for developing sex-specific interventions for asthma, addressing the higher prevalence and severity observed in women. In this study, we demonstrate that exposure to house dust mite in the mouse lung is associated with epigenetic alterations in genes linked to airway hyperresponsiveness and lung inflammation. These alterations were dependent on the presence or absence of estrogen receptors.

Animals↗

PubMed2003

Improving the Arabidopsis genome annotation using maximal transcript alignment assemblies.

The spliced alignment of expressed sequence data to genomic sequence has proven a key tool in the comprehensive annotation of genes in eukaryotic genomes. A novel algorithm was developed to assemble clusters of overlapping transcript alignments (ESTs and full-length cDNAs) into maximal alignment assemblies, thereby comprehensively incorporating all available transcript data and capturing subtle splicing variations. Complete and partial gene structures identified by this method were used to improve The Institute for Genomic Research Arabidopsis genome annotation (TIGR release v.4.0). The alignment assemblies permitted the automated modeling of several novel genes and >1000 alternative splicing variations as well as updates (including UTR annotations) to nearly half of the approximately 27 000 annotated protein coding genes. The algorithm of the Program to Assemble Spliced Alignments (PASA) tool is described, as well as the results of automated updates to Arabidopsis gene annotations.

Algorithms↗

PubMed2003

The dog genome: survey sequencing and comparative analysis.

A survey of the dog genome sequence (6.22 million sequence reads; 1.5x coverage) demonstrates the power of sample sequencing for comparative analysis of mammalian genomes and the generation of species-specific resources. More than 650 million base pairs (>25%) of dog sequence align uniquely to the human genome, including fragments of putative orthologs for 18,473 of 24,567 annotated human genes. Mutation rates, conserved synteny, repeat content, and phylogeny can be compared among human, mouse, and dog. A variety of polymorphic elements are identified that will be valuable for mapping the genetic basis of diseases and traits in the dog.

Animals↗

PubMed2002

The genome sequence of the malaria mosquito Anopheles gambiae.

Anopheles gambiae is the principal vector of malaria, a disease that afflicts more than 500 million people and causes more than 1 million deaths each year. Tenfold shotgun sequence coverage was obtained from the PEST strain of A. gambiae and assembled into scaffolds that span 278 million base pairs. A total of 91% of the genome was organized in 303 scaffolds; the largest scaffold was 23.1 million base pairs. There was substantial genetic variation within this strain, and the apparent existence of two haplotypes of approximately equal frequency ("dual haplotypes") in a substantial fraction of the genome likely reflects the outbred nature of the PEST strain. The sequence produced a conservative inference of more than 400,000 single-nucleotide polymorphisms that showed a markedly bimodal density distribution. Analysis of the genome sequence revealed strong evidence for about 14,000 protein-encoding transcripts. Prominent expansions in specific families of proteins likely involved in cell adhesion and immunity were noted. An expressed sequence tag analysis of genes regulated by blood feeding provided insights into the physiological adaptations of a hematophagous insect.

Animals↗

PubMed2002

A comparison of whole-genome shotgun-derived mouse chromosome 16 and the human genome.

The high degree of similarity between the mouse and human genomes is demonstrated through analysis of the sequence of mouse chromosome 16 (Mmu 16), which was obtained as part of a whole-genome shotgun assembly of the mouse genome. The mouse genome is about 10% smaller than the human genome, owing to a lower repetitive DNA content. Comparison of the structure and protein-coding potential of Mmu 16 with that of the homologous segments of the human genome identifies regions of conserved synteny with human chromosomes (Hsa) 3, 8, 12, 16, 21, and 22. Gene content and order are highly conserved between Mmu 16 and the syntenic blocks of the human genome. Of the 731 predicted genes on Mmu 16, 509 align with orthologs on the corresponding portions of the human genome, 44 are likely paralogous to these genes, and 164 genes have homologs elsewhere in the human genome; there are 14 genes for which we could find no human counterpart.

Animals↗