Variability in the Insect and Plant Adhesins, Mad1 and Mad2, within the Fungal Genus Metarhizium Suggest Plant Adaptation as an Evolutionary Force

Although recent studies suggest that the plant cytoskeleton is associated with plant stress responses, such as salt, cold, and drought, the molecular mechanism underlying microtubule function in plant salt stress response remains unclear. We performed a comparative proteomic analysis between control suspension-cultured cells (A0) and salt-adapted cells (A120) established from Arabidopsis root callus to investigate plant adaptation mechanisms to long-term salt stress. We identified 50 differentially expressed proteins (45 up- and 5 down-regulated proteins) in A120 cells compared with A0 cells. Gene ontology enrichment and protein network analyses indicated that differentially expressed proteins in A120 cells were strongly associated with cell structure-associated clusters, including cytoskeleton and cell wall biogenesis. Gene expression analysis revealed that expressions of cytoskeleton-related genes, such as FBA8, TUB3, TUB4, TUB7, TUB9, and ACT7, and a cell wall biogenesis-related gene, CCoAOMT1, were induced in salt-adapted A120 cells. Moreover, the loss-of-function mutant of Arabidopsis TUB9 gene, tub9, showed a hypersensitive phenotype to salt stress. Consistent overexpression of Arabidopsis TUB9 gene in rice transgenic plants enhanced tolerance to salt stress. Our results suggest that microtubules play crucial roles in plant adaptation and tolerance to salt stress. The modulation of microtubule-related gene expression can be an effective strategy for developing salt-tolerant crops.

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Microbial Associations with Pancreatic Cancer: A New Frontier in Biomarkers

Cancers ◽

10.3390/cancers13153784 ◽

2021 ◽

Vol 13 (15) ◽

pp. 3784

Author(s):

Mark Stasiewicz ◽

Marek Kwaśniewski ◽

Tomasz M. Karpiński

Keyword(s):

Pancreatic Cancer ◽

Helicobacter Pylori ◽

Survival Rates ◽

Health Concern ◽

Current State ◽

Increased Risk ◽

Microbial Biomarkers ◽

New Frontier ◽

Microbial Associations ◽

Fungal Genus

Pancreatic cancer (PC) remains a global health concern with high mortality and is expected to increase as a proportion of overall cancer cases in the coming years. Most patients are diagnosed at a late stage of disease progression, which contributes to the extremely low 5-year survival rates. Presently, screening for PC remains costly and time consuming, precluding the use of widespread testing. Biomarkers have been explored as an option by which to ameliorate this situation. The authors conducted a search of available literature on PubMed to present the current state of understanding as it pertains to the use of microbial biomarkers and their associations with PC. Carriage of certain bacteria in the oral cavity (e.g., Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Streptococcus sp.), gut (e.g., Helicobacter pylori, Synergistetes, Proteobacteria), and pancreas (e.g., Fusobacterium sp., Enterobacteriaceae, Pseudomonadaceae) has been associated with an increased risk of developing PC. Additionally, the fungal genus Malassezia has likewise been associated with PC development. This review further outlines potential oncogenic mechanisms involved in the microbial-associated development of PC.

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Vanishing GC-Rich Isochores in Mammalian Genomes

Genetics ◽

10.1093/genetics/162.4.1837 ◽

2002 ◽

Vol 162 (4) ◽

pp. 1837-1847 ◽

Cited By ~ 6

Author(s):

Laurent Duret ◽

Marie Semon ◽

Gwenaël Piganeau ◽

Dominique Mouchiroud ◽

Nicolas Galtier

Keyword(s):

Gc Content ◽

Synonymous Substitution ◽

Equilibrium Analysis ◽

Large Excess ◽

Substitution Pattern ◽

Origin And Evolution ◽

Evolutionary Force ◽

Mammalian Genomes ◽

Human Polymorphism ◽

Probability Of Fixation

AbstractTo understand the origin and evolution of isochores—the peculiar spatial distribution of GC content within mammalian genomes—we analyzed the synonymous substitution pattern in coding sequences from closely related species in different mammalian orders. In primate and cetartiodactyls, GC-rich genes are undergoing a large excess of GC → AT substitutions over AT → GC substitutions: GC-rich isochores are slowly disappearing from the genome of these two mammalian orders. In rodents, our analyses suggest both a decrease in GC content of GC-rich isochores and an increase in GC-poor isochores, but more data will be necessary to assess the significance of this pattern. These observations question the conclusions of previous works that assumed that base composition was at equilibrium. Analysis of allele frequency in human polymorphism data, however, confirmed that in the GC-rich parts of the genome, GC alleles have a higher probability of fixation than AT alleles. This fixation bias appears not strong enough to overcome the large excess of GC → AT mutations. Thus, whatever the evolutionary force (neutral or selective) at the origin of GC-rich isochores, this force is no longer effective in mammals. We propose a model based on the biased gene conversion hypothesis that accounts for the origin of GC-rich isochores in the ancestral amniote genome and for their decline in present-day mammals.

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Neogene diversification in the temperate lichen-forming fungal genus Parmelia (Parmeliaceae, Ascomycota)

Systematics and Biodiversity ◽

10.1080/14772000.2016.1226977 ◽

2016 ◽

Vol 15 (2) ◽

pp. 166-181 ◽

Cited By ~ 7

Author(s):

M. Carmen Molina ◽

Pradeep K. Divakar ◽

Trevor Goward ◽

Ana M. Millanes ◽

H. Thorsten Lumbsch ◽

...

Keyword(s):

Fungal Genus

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An Exon-Based Comparative Variant Analysis Pipeline to Study the Scale and Role of Frameshift and Nonsense Mutation in the Human-Chimpanzee Divergence

Comparative and Functional Genomics ◽

10.1155/2009/406421 ◽

2009 ◽

Vol 2009 ◽

pp. 1-19 ◽

Cited By ~ 1

Author(s):

GongXin Yu

Keyword(s):

Molecular Mechanisms ◽

Inflammatory Diseases ◽

Cell Lineage ◽

Nonsense Mutations ◽

Less Is More ◽

Sequencing Errors ◽

Evolutionary Force ◽

Variant Analysis ◽

Species Specific

Chimpanzees and humans are closely related but differ in many deadly human diseases and other characteristics in physiology, anatomy, and pathology. In spite of decades of extensive research, crucial questions about the molecular mechanisms behind the differences are yet to be understood. Here I reportExonVar, a novel computational pipeline forExon-based human-chimpanzee comparativeVariant analysis. The objective is to comparatively analyze mutations specifically those that caused the frameshift and nonsense mutations and to assess their scale and potential impacts on human-chimpanzee divergence. Genomewide analysis of human and chimpanzee exons withExonVaridentified a number of species-specific, exon-disrupting mutations in chimpanzees but much fewer in humans. Many were found on genes involved in important biological processes such as T cell lineage development, the pathogenesis of inflammatory diseases, and antigen induced cell death. A “less-is-more” model was previously established to illustrate the role of the gene inactivation and disruptions during human evolution. Here this analysis suggested a different model where the chimpanzee-specific exon-disrupting mutations may act as additional evolutionary force that drove the human-chimpanzee divergence. Finally, the analysis revealed a number of sequencing errors in the chimpanzee and human genome sequences and further illustrated that they could be corrected without resequencing.

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