Molecular defense responses to natural enemies determine seedling survival in a subtropical forest

Negative density dependence (NDD) has been accepted as a key mechanism for biodiversity maintenance in natural forests and different lineages of natural enemies (fungus, bacterium, insect and virus) may be involved. Previous NDD related studies usually correlated seedling survival to the density of host-specific pests or pathogens along the distance to conspecific neighbors, and molecular defense responses of focal seedlings to natural enemies were seldomly concerned. By employing community functional genomics strategy, we extracted copy numbers of homologous genes in defense responses from transcriptomic data of 99 tree species and their inherent impacts on seedling survival were evaluated using partial linear regression analysis and general linear mixed-effects models. The community-level transcriptomic gene copy number of defense responses to fungus, insect and virus showed significant negative correlations with survival rates of the seedling community and the species-level gene copy number of defense response to insect significantly correlated with survival rates of top-twenty common seedling species. Moreover, presence of adult neighbors with distinct defense response to bacterial and viral pathogens survival of focal seedlings as predicted by NDD, while presence of seedling neighbors with similar defense response to insect tended to promote survival of focal seedlings which may be driven by insect-mediated biotic filtering or competitive exclusion. We conclude that both gene copy number and dissimilarities to adult and seedling neighbors in defense response to natural enemies determined seedling survival, indicating the critical contributions of molecular defense responses of plants to species coexistence and diversity maintenance in subtropical forests.

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Epidermal Growth Factor Receptor Inhibitor Gefitinib Added to Chemoradiotherapy in Locally Advanced Head and Neck Cancer

Journal of Clinical Oncology ◽

10.1200/jco.2009.27.0397 ◽

2010 ◽

Vol 28 (20) ◽

pp. 3336-3343 ◽

Cited By ~ 56

Author(s):

Ezra E.W. Cohen ◽

Daniel J. Haraf ◽

Rangesh Kunnavakkam ◽

Kerstin M. Stenson ◽

Elizabeth A. Blair ◽

...

Keyword(s):

Epidermal Growth Factor Receptor ◽

Copy Number ◽

Locally Advanced ◽

Survival Rates ◽

Gene Copy Number ◽

Growth Factor Receptor ◽

Gene Copy ◽

Advanced Head ◽

Egfr Gene ◽

Epidermal Growth

Purpose Assess efficacy and toxicity of gefitinib, an epidermal growth factor receptor (EGFR) inhibitor, added to, and in maintenance after, concurrent chemoradiotherapy (CCRT) in locally advanced head and neck cancer (LA-HNC) and correlate outcomes with EGFR gene copy number alterations. Patients and Methods Patients with stage III to IV LA-HNC received two cycles of carboplatin/paclitaxel induction chemotherapy (IC) followed by split-course CCRT with fluorouracil, hydroxyurea, twice daily radiotherapy (FHX), and gefitinib (250 mg daily) followed by continued gefitinib for 2 years total. The primary end point was complete response (CR) rate after CCRT. EGFR gene copy number was assessed by fluorescent in situ hybridization. Results Sixty-nine patients (66 with stage IV disease, 37 with oropharynx primary tumors, and 67 with performance status 0 to 1) were enrolled with a median age of 55 years. Predominant grade 3 or 4 toxicities during IC and CCRT were neutropenia (n = 20) and in-field mucositis (n = 59) and dermatitis (n = 23), respectively. CR rate after CCRT was 90%. After median follow-up of 3.5 years, 4-year overall, progression-free, and disease-specific survival rates were 74%, 72%, and 89%, respectively. To date, one patient has developed a second primary tumor in the aerodigestive tract. In 31 patients with available tissue, high EGFR gene copy number was associated with worse overall survival (P = .02). Conclusion Gefitinib can be administered with FHX and as maintenance therapy for at least 2 years, demonstrating CR and survival rates that compare favorably with prior experience. High EGFR gene copy number may be associated with poor outcome in patients with LA-HNC treated with this regimen.

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Assessment of HER-2/neu, с-MYC and CCNE1 gene copy number variations and protein expression in endometrial carcinomas

Experimental Oncology ◽

10.32471/exp-oncology.2312-8852.vol-41-no-2.12973 ◽

2019 ◽

Vol 41 (2) ◽

Author(s):

L.G. Buchynska ◽

◽

O.V. Brieieva* ◽

N.P. Iurchenko ◽

◽

...

Keyword(s):

Protein Expression ◽

Copy Number ◽

Gene Copy Number ◽

Copy Number Variations ◽

Gene Copy ◽

Her 2 ◽

Endometrial Carcinomas

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Faculty Opinions recommendation of Diet and the evolution of human amylase gene copy number variation.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1092307.546722 ◽

2007 ◽

Author(s):

Magnus Ingelman-Sundberg

Keyword(s):

Copy Number Variation ◽

Copy Number ◽

Gene Copy Number ◽

Gene Copy ◽

Amylase Gene ◽

Gene Copy Number Variation ◽

Number Variation

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Faculty Opinions recommendation of RNA polymerase I activators count and adjust ribosomal RNA gene copy number.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.734776122.793556076 ◽

2019 ◽

Author(s):

Angela Taddei

Keyword(s):

Rna Polymerase ◽

Ribosomal Rna ◽

Copy Number ◽

Gene Copy Number ◽

Rna Polymerase I ◽

Gene Copy ◽

Ribosomal Rna Gene ◽

Polymerase I

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Estimating Copy-Number Proportions: The Comeback of Sanger Sequencing

Genes ◽

10.3390/genes12020283 ◽

2021 ◽

Vol 12 (2) ◽

pp. 283

Author(s):

Eyal Seroussi

Keyword(s):

Copy Number ◽

Sanger Sequencing ◽

Cytosine Methylation ◽

Direct Sequencing ◽

Information Source ◽

Gene Copy Number ◽

Cost Effective ◽

Gene Copy ◽

Base Editing ◽

Recent Developments

Determination of the relative copy numbers of mixed molecular species in nucleic acid samples is often the objective of biological experiments, including Single-Nucleotide Polymorphism (SNP), indel and gene copy-number characterization, and quantification of CRISPR-Cas9 base editing, cytosine methylation, and RNA editing. Standard dye-terminator chromatograms are a widely accessible, cost-effective information source from which copy-number proportions can be inferred. However, the rate of incorporation of dye terminators is dependent on the dye type, the adjacent sequence string, and the secondary structure of the sequenced strand. These variable rates complicate inferences and have driven scientists to resort to complex and costly quantification methods. Because these complex methods introduce their own biases, researchers are rethinking whether rectifying distortions in sequencing trace files and using direct sequencing for quantification will enable comparable accurate assessment. Indeed, recent developments in software tools (e.g., TIDE, ICE, EditR, BEEP and BEAT) indicate that quantification based on direct Sanger sequencing is gaining in scientific acceptance. This commentary reviews the common obstacles in quantification and the latest insights and developments relevant to estimating copy-number proportions based on direct Sanger sequencing, concluding that bidirectional sequencing and sophisticated base calling are the keys to identifying and avoiding sequence distortions.

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Nongenotoxic ABCB1 activator tetraphenylphosphonium can contribute to doxorubicin resistance in MX-1 breast cancer cell line

Scientific Reports ◽

10.1038/s41598-021-86120-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Raimonda Kubiliute ◽

Indre Januskeviciene ◽

Ruta Urbanaviciute ◽

Kristina Daniunaite ◽

Monika Drobniene ◽

...

Keyword(s):

Breast Cancer ◽

Cell Line ◽

Protein Level ◽

Copy Number ◽

Gene Copy Number ◽

Gene Copy ◽

Common Mechanism ◽

Dna Hypomethylation ◽

Mesenchymal Transition ◽

Molecular Features

AbstractHyperactivation of ABC transporter ABCB1 and induction of epithelial–mesenchymal transition (EMT) are the most common mechanism of acquired cancer chemoresistance. This study describes possible mechanisms, that might contribute to upregulation of ABCB1 and synergistically boost the acquisition of doxorubicin (DOX) resistance in breast cancer MX-1 cell line. DOX resistance in MX-1 cell line was induced by a stepwise increase of drug concentration or by pretreatment of cells with an ABCB1 transporter activator tetraphenylphosphonium (TPP+) followed by DOX exposure. Transcriptome analysis of derived cells was performed by human gene expression microarrays and by quantitative PCR. Genetic and epigenetic mechanisms of ABCB1 regulation were evaluated by pyrosequencing and gene copy number variation analysis. Gradual activation of canonical EMT transcription factors with later activation of ABCB1 at the transcript level was observed in DOX-only treated cells, while TPP+ exposure induced considerable activation of ABCB1 at both, mRNA and protein level. The changes in ABCB1 mRNA and protein level were related to the promoter DNA hypomethylation and the increase in gene copy number. ABCB1-active cells were highly resistant to DOX and showed morphological and molecular features of EMT. The study suggests that nongenotoxic ABCB1 inducer can possibly accelerate development of DOX resistance.

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