Sequence of the supernumerary B chromosome of maize provides insight into its drive mechanism and evolution

B chromosomes are enigmatic elements in thousands of plant and animal genomes that persist in populations despite being nonessential. They circumvent the laws of Mendelian inheritance but the molecular mechanisms underlying this behavior remain unknown. Here we present the sequence, annotation, and analysis of the maize B chromosome providing insight into its drive mechanism. The sequence assembly reveals detailed locations of the elements involved with the cis and trans functions of its drive mechanism, consisting of nondisjunction at the second pollen mitosis and preferential fertilization of the egg by the B-containing sperm. We identified 758 protein-coding genes in 125.9 Mb of B chromosome sequence, of which at least 88 are expressed. Our results demonstrate that transposable elements in the B chromosome are shared with the standard A chromosome set but multiple lines of evidence fail to detect a syntenic genic region in the A chromosomes, suggesting a distant origin. The current gene content is a result of continuous transfer from the A chromosomal complement over an extended evolutionary time with subsequent degradation but with selection for maintenance of this nonvital chromosome.

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Extensive Horizontal Gene Transfer in Cheese-Associated Bacteria

10.1101/079137 ◽

2016 ◽

Cited By ~ 1

Author(s):

Kevin S. Bonham ◽

Benjamin E. Wolfe ◽

Rachel J. Dutton

Keyword(s):

Gene Transfer ◽

Horizontal Gene Transfer ◽

Molecular Mechanisms ◽

Protein Coding ◽

Associated Bacteria ◽

The Us ◽

Selective Forces ◽

Genomic Regions ◽

Microbiome Assembly ◽

Insight Into

AbstractAcquisition of genes through horizontal gene transfer (HGT) allows microbes to rapidly gain new capabilities and adapt to new or changing environments. Identifying widespread HGT regions within multispecies microbiomes can pinpoint the molecular mechanisms that play key roles in microbiome assembly. We sought to identify horizontally transferred genes within a model microbiome, the cheese rind. Comparing 31 newly-sequenced and 134 previously sequenced bacterial isolates from cheese rinds, we identified over 200 putative horizontally transferred genomic regions containing 4,733 protein coding genes. The largest of these regions are enriched for genes involved in siderophore acquisition, and are widely distributed in cheese rinds in both Europe and the US. These results suggest that horizontal gene transfer (HGT) is prevalent in cheese rind microbiomes, and the identification of genes that are frequently transferred in a particular environment may provide insight into the selective forces shaping microbial communities.

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Locating a site on the maize B chromosome that controls preferential fertilization

Genome ◽

10.1139/g07-035 ◽

2007 ◽

Vol 50 (6) ◽

pp. 578-587 ◽

Cited By ~ 9

Author(s):

Wayne R. Carlson

Keyword(s):

B Chromosome ◽

B Chromosomes ◽

Chromosome 9 ◽

Chromosome Deletion ◽

Pollen Mitosis ◽

Preferential Fertilization ◽

Second Pollen Mitosis ◽

A Site ◽

Derivatives Of

In maize, the B chromosome can undergo nondisjunction at the second pollen mitosis, producing sperm with two B chromosomes and sperm with zero B chromosomes. Preferential fertilization is the ability of the sperm carrying two B chromosomes to transmit more frequently to the embryo of a kernel than the sperm lacking the B chromosome. A translocation involving the B chromosome and chromosome 9, TB-9Sb, has been used to study preferential fertilization. The B-9 chromosome has the same properties of nondisjunction and preferential fertilization as the standard B chromosome. Deletion derivatives of B-9, which lack the centric heterochromatin and possibly some adjacent euchromatin, were tested for their ability to induce preferential fertilization. They were found to lack the capacity for preferential fertilization.

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De novo transcriptome assembly of the Italian white truffle (Tuber magnatum Pico)

10.1101/461483 ◽

2018 ◽

Cited By ~ 1

Author(s):

Federico Vita ◽

Amedeo Alpi ◽

Edoardo Bertolini

Keyword(s):

Molecular Mechanisms ◽

De Novo ◽

Transcriptome Assembly ◽

Rna Seq ◽

Genetic Studies ◽

Protein Coding ◽

Important Species ◽

White Truffle ◽

Tuber Magnatum ◽

Insight Into

AbstractThe Italian white truffle (Tuber magnatum Pico) is a gastronomic delicacy that dominates the worldwide truffle market. Despite its importance, the genomic resources currently available for this species are still limited. Here we present the first de novo transcriptome assembly of T. magnatum. Illumina RNA-seq data were assembled using a single-k-mer approach into 22,932 transcripts with N50 of 1,524 bp. Our approach allowed to predict and annotate 12,367 putative protein coding sequences, reunited in 6,723 loci. In addition, we identified 2,581 gene-based SSR markers. This work provides the first publicly available reference transcriptome for genomics and genetic studies providing insight into the molecular mechanisms underlying the biology of this important species.

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Mapping OMIM Disease–Related Variations on Protein Domains Reveals an Association Among Variation Type, Pfam Models, and Disease Classes

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2021.617016 ◽

2021 ◽

Vol 8 ◽

Author(s):

Castrense Savojardo ◽

Giulia Babbi ◽

Pier Luigi Martelli ◽

Rita Casadio

Keyword(s):

Human Disease ◽

Molecular Mechanisms ◽

Current Knowledge ◽

Genetic Diseases ◽

Mendelian Inheritance ◽

Protein Coding ◽

Related Variation ◽

Diagnosis And Prognosis ◽

Specific Association ◽

Physical Features

Human genome resequencing projects provide an unprecedented amount of data about single-nucleotide variations occurring in protein-coding regions and often leading to observable changes in the covalent structure of gene products. For many of these variations, links to Online Mendelian Inheritance in Man (OMIM) genetic diseases are available and are reported in many databases that are collecting human variation data such as Humsavar. However, the current knowledge on the molecular mechanisms that are leading to diseases is, in many cases, still limited. For understanding the complex mechanisms behind disease insurgence, the identification of putative models, when considering the protein structure and chemico-physical features of the variations, can be useful in many contexts, including early diagnosis and prognosis. In this study, we investigate the occurrence and distribution of human disease–related variations in the context of Pfam domains. The aim of this study is the identification and characterization of Pfam domains that are statistically more likely to be associated with disease-related variations. The study takes into consideration 2,513 human protein sequences with 22,763 disease-related variations. We describe patterns of disease-related variation types in biunivocal relation with Pfam domains, which are likely to be possible markers for linking Pfam domains to OMIM diseases. Furthermore, we take advantage of the specific association between disease-related variation types and Pfam domains for clustering diseases according to the Human Disease Ontology, and we establish a relation among variation types, Pfam domains, and disease classes. We find that Pfam models are specific markers of patterns of variation types and that they can serve to bridge genes, diseases, and disease classes. Data are available as Supplementary Material for 1,670 Pfam models, including 22,763 disease-related variations associated to 3,257 OMIM diseases.

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Extensive horizontal gene transfer in cheese-associated bacteria

eLife ◽

10.7554/elife.22144 ◽

2017 ◽

Vol 6 ◽

Cited By ~ 41

Author(s):

Kevin S Bonham ◽

Benjamin E Wolfe ◽

Rachel J Dutton

Keyword(s):

Gene Transfer ◽

Horizontal Gene Transfer ◽

Molecular Mechanisms ◽

Protein Coding ◽

Associated Bacteria ◽

The Us ◽

Selective Forces ◽

Genomic Regions ◽

Microbiome Assembly ◽

Insight Into

Acquisition of genes through horizontal gene transfer (HGT) allows microbes to rapidly gain new capabilities and adapt to new or changing environments. Identifying widespread HGT regions within multispecies microbiomes can pinpoint the molecular mechanisms that play key roles in microbiome assembly. We sought to identify horizontally transferred genes within a model microbiome, the cheese rind. Comparing 31 newly sequenced and 134 previously sequenced bacterial isolates from cheese rinds, we identified over 200 putative horizontally transferred genomic regions containing 4733 protein coding genes. The largest of these regions are enriched for genes involved in siderophore acquisition, and are widely distributed in cheese rinds in both Europe and the US. These results suggest that HGT is prevalent in cheese rind microbiomes, and that identification of genes that are frequently transferred in a particular environment may provide insight into the selective forces shaping microbial communities.

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Clinical Candidates Targeting the ATR–CHK1–WEE1 Axis in Cancer

Cancers ◽

10.3390/cancers13040795 ◽

2021 ◽

Vol 13 (4) ◽

pp. 795

Author(s):

Lukas Gorecki ◽

Martin Andrs ◽

Jan Korabecny

Keyword(s):

Cell Cycle ◽

Cancer Cells ◽

Molecular Mechanisms ◽

Patient Survival ◽

Current Status ◽

Future Perspectives ◽

Phase Ii Trials ◽

Anticancer Treatment ◽

Positive Outlook ◽

Insight Into

Selective killing of cancer cells while sparing healthy ones is the principle of the perfect cancer treatment and the primary aim of many oncologists, molecular biologists, and medicinal chemists. To achieve this goal, it is crucial to understand the molecular mechanisms that distinguish cancer cells from healthy ones. Accordingly, several clinical candidates that use particular mutations in cell-cycle progressions have been developed to kill cancer cells. As the majority of cancer cells have defects in G1 control, targeting the subsequent intra‑S or G2/M checkpoints has also been extensively pursued. This review focuses on clinical candidates that target the kinases involved in intra‑S and G2/M checkpoints, namely, ATR, CHK1, and WEE1 inhibitors. It provides insight into their current status and future perspectives for anticancer treatment. Overall, even though CHK1 inhibitors are still far from clinical establishment, promising accomplishments with ATR and WEE1 inhibitors in phase II trials present a positive outlook for patient survival.

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LINC01089 suppresses lung adenocarcinoma cell proliferation and migration via miR-301b-3p/STARD13 axis

BMC Pulmonary Medicine ◽

10.1186/s12890-021-01568-6 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Ye Qian ◽

Yan Zhang ◽

Haoming Ji ◽

Yucheng Shen ◽

Liangfeng Zheng ◽

...

Keyword(s):

Cell Proliferation ◽

Lung Adenocarcinoma ◽

High Morbidity ◽

Lipid Transfer ◽

Protein Coding ◽

Cell Proliferation And Migration ◽

Reduce Cell Proliferation ◽

And Migration ◽

Insight Into ◽

Proliferation And Migration

Abstract Background Lung adenocarcinoma (LUAD) is one of the most common cancers with high morbidity and mortality worldwide. Long non-coding RNAs (lncRNAs) serve as tumor promoters or suppressors in the development of various human malignancies, including LUAD. Although long intergenic non-protein coding RNA 1089 (LINC01089) suppresses the progression of breast cancer, its mechanism in LUAD requires further exploration. Thus, we aimed to investigate the underlying function and mechanism of LINC01089 in LUAD. Methods The expression of LINC01089 in LUAD and normal cell lines was detected. Functional assays were applied to measure cell proliferation, apoptosis and migration. Besides, mechanism experiments were employed for assessing the interplay among LINC01089, miR-301b-3p and StAR related lipid transfer domain containing 13 (STARD13). Data achieved in this study was statistically analyzed with Student’s t test or one-way analysis of variance. Results LINC01089 expression was significantly down-regulated in LUAD tissues and cells and its overexpression could reduce cell proliferation and migration. Moreover, LINC01089 could regulate STARD13 expression through competitively binding to miR-301b-3p in LUAD. Additionally, rescue assays uncovered that STARD13 depletion or miR-301b-3p overexpression could countervail the restraining effect of LINC01089 knockdown on the phenotypes of LUAD cells. Conclusion LINC01089 served as a tumor-inhibitor in LUAD by targeting miR-301b-3p/STARD13 axis, providing an innovative insight into LUAD therapies. Trial registration Not applicable.

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Molecular Pathways Involved in the Development of Congenital Erythrocytosis

Genes ◽

10.3390/genes12081150 ◽

2021 ◽

Vol 12 (8) ◽

pp. 1150

Author(s):

Jana Tomc ◽

Nataša Debeljak

Keyword(s):

Signal Transduction ◽

Iron Homeostasis ◽

Molecular Mechanisms ◽

Oxygen Affinity ◽

Molecular Pathways ◽

Disease Development ◽

Post Translational Modifications ◽

Hemoglobin Oxygen Affinity ◽

Insight Into ◽

Idiopathic Erythrocytosis

Patients with idiopathic erythrocytosis are directed to targeted genetic testing including nine genes involved in oxygen sensing pathway in kidneys, erythropoietin signal transduction in pre-erythrocytes and hemoglobin-oxygen affinity regulation in mature erythrocytes. However, in more than 60% of cases the genetic cause remains undiagnosed, suggesting that other genes and mechanisms must be involved in the disease development. This review aims to explore additional molecular mechanisms in recognized erythrocytosis pathways and propose new pathways associated with this rare hematological disorder. For this purpose, a comprehensive review of the literature was performed and different in silico tools were used. We identified genes involved in several mechanisms and molecular pathways, including mRNA transcriptional regulation, post-translational modifications, membrane transport, regulation of signal transduction, glucose metabolism and iron homeostasis, which have the potential to influence the main erythrocytosis-associated pathways. We provide valuable theoretical information for deeper insight into possible mechanisms of disease development. This information can be also helpful to improve the current diagnostic solutions for patients with idiopathic erythrocytosis.

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Pathomechanisms in the Kidneys in Selected Protozoan Parasitic Infections

International Journal of Molecular Sciences ◽

10.3390/ijms22084209 ◽

2021 ◽

Vol 22 (8) ◽

pp. 4209

Author(s):

Karolina Kot ◽

Natalia Łanocha-Arendarczyk ◽

Michał Ptak ◽

Aleksandra Łanocha ◽

Elżbieta Kalisińska ◽

...

Keyword(s):

Toxoplasma Gondii ◽

Molecular Mechanisms ◽

Kidney Injury ◽

Therapeutic Interventions ◽

Parasitic Infections ◽

Injury Mechanisms ◽

Kidney Involvement ◽

Leishmania Spp ◽

Apoptosis Process ◽

Insight Into

Leishmaniasis, malaria, toxoplasmosis, and acanthamoebiasis are protozoan parasitic infections. They remain important contributors to the development of kidney disease, which is associated with increased patients’ morbidity and mortality. Kidney injury mechanisms are not fully understood in protozoan parasitic diseases, bringing major difficulties to specific therapeutic interventions. The aim of this review is to present the biochemical and molecular mechanisms in kidneys infected with Leishmania spp., Plasmodium spp., Toxoplasma gondii, and Acanthamoeba spp. We present available mechanisms of an immune response, oxidative stress, apoptosis process, hypoxia, biomarkers of renal injury in the serum or urine, and the histopathological changes of kidneys infected with the selected parasites. Pathomechanisms of Leishmania spp. and Plasmodium spp. infections have been deeply investigated, while Toxoplasma gondii and Acanthamoeba spp. infections in the kidneys are not well known yet. Deeper knowledge of kidney involvement in leishmaniasis and malaria by presenting their mechanisms provides insight into how to create novel and effective treatments. Additionally, the presented work shows gaps in the pathophysiology of renal toxoplasmosis and acanthamoebiasis, which need further research.

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The apple C2H2-type zinc finger transcription factor MdZAT10 positively regulates JA-induced leaf senescence by interacting with MdBT2

Horticulture Research ◽

10.1038/s41438-021-00593-0 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Kuo Yang ◽

Jian-Ping An ◽

Chong-Yang Li ◽

Xue-Na Shen ◽

Ya-Jing Liu ◽

...

Keyword(s):

Mass Spectrometry ◽

Transcription Factor ◽

Liquid Chromatography ◽

Zinc Finger ◽

Leaf Senescence ◽

Transcriptional Activity ◽

Molecular Mechanisms ◽

Liquid Chromatography Mass Spectrometry ◽

Zinc Finger Transcription Factor ◽

Insight Into

AbstractJasmonic acid (JA) plays an important role in regulating leaf senescence. However, the molecular mechanisms of leaf senescence in apple (Malus domestica) remain elusive. In this study, we found that MdZAT10, a C2H2-type zinc finger transcription factor (TF) in apple, markedly accelerates leaf senescence and increases the expression of senescence-related genes. To explore how MdZAT10 promotes leaf senescence, we carried out liquid chromatography/mass spectrometry screening. We found that MdABI5 physically interacts with MdZAT10. MdABI5, an important positive regulator of leaf senescence, significantly accelerated leaf senescence in apple. MdZAT10 was found to enhance the transcriptional activity of MdABI5 for MdNYC1 and MdNYE1, thus accelerating leaf senescence. In addition, we found that MdZAT10 expression was induced by methyl jasmonate (MeJA), which accelerated JA-induced leaf senescence. We also found that the JA-responsive protein MdBT2 directly interacts with MdZAT10 and reduces its protein stability through ubiquitination and degradation, thereby delaying MdZAT10-mediated leaf senescence. Taken together, our results provide new insight into the mechanisms by which MdZAT10 positively regulates JA-induced leaf senescence in apple.

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