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Differential Expression Of Cyb5a In Chinese And European Pig Breeds Due To Genetic Variations In The Promoter Region..Pdf, Ying Bai, Jibin Zhang, Y Xue, Yl Peng, Gang Chen, Meiying Fang Dec 2015

Differential Expression Of Cyb5a In Chinese And European Pig Breeds Due To Genetic Variations In The Promoter Region..Pdf, Ying Bai, Jibin Zhang, Y Xue, Yl Peng, Gang Chen, Meiying Fang

Jibin Zhang

Cytochrome b5 (CYB5A) is an important electron transfer protein with homologues in a number of different organisms. In pigs, CYB5A is related to boar taint because of its role in androstenone biosynthesis. To determine the variety of CYB5A expression in pig breeds, genetic variations in the porcine CYB5A promoter region in both Chinese and European pig breeds were examined. Three single nucleotide polymorphisms (NC_010443.4:
g.165901487delG, g.165901767T>C and g.165902078C>T) were identified in the porcine CYB5A promoter region. These SNPs occurred in different frequencies in Chinese and European pigs. Chinese pigs were primarily haplotype B (denoted as delG-C-T: the position of nt …


Language And Literacy Development In Individuals With Velo­‐Cardio­‐Facial Syndrome, Kevin Antshel, Eileen Marrinan, Wendy Kates, Wanda Fremont, Robert Shprintzen Dec 2015

Language And Literacy Development In Individuals With Velo­‐Cardio­‐Facial Syndrome, Kevin Antshel, Eileen Marrinan, Wendy Kates, Wanda Fremont, Robert Shprintzen

Robert J. Shprintzen

Velo-cardio-facial syndrome (VCFS) is a genetic disorder caused by a microdeletion of chromosome 22q11.2. Although there is some variability, VCFS is associated with a characteristic physical, behavioral, and cognitive phenotype. This review article focuses on aspects of language and literacy development in VCFS, describing what is known and offering avenues for future research. The most consistently reported language and literacy findings in the VCFS population include reading, spelling, phonological processing, and auditory verbal rote memory abilities as areas of relative strength. Receptive language abilities are noted to be relatively stronger than expressive language abilities in individuals with VCFS. Speech disorders …


Atlas-Based White Matter Analysis In Individuals With Velo-Cardio-Facial Syndrome (22q11.2 Deletion Syndrome) And Unaffected Siblings, Petya Radoeva, Ioana Coman, Kevin Antshel, Wanda Fremont, Christopher Mccarthy, Ashwini Kotkar, Dongliang Wang, Robert Shprintzen, Wendy Kates Dec 2015

Atlas-Based White Matter Analysis In Individuals With Velo-Cardio-Facial Syndrome (22q11.2 Deletion Syndrome) And Unaffected Siblings, Petya Radoeva, Ioana Coman, Kevin Antshel, Wanda Fremont, Christopher Mccarthy, Ashwini Kotkar, Dongliang Wang, Robert Shprintzen, Wendy Kates

Robert J. Shprintzen

Background: Velo-cardio-facial syndrome (VCFS, MIM#192430, 22q11.2 Deletion Syndrome) is a genetic disorder caused by a deletion of about 40 genes at the q11.2 band of one copy of chromosome 22. Individuals with VCFS present with deficits in cognition and social functioning, high risk of psychiatric disorders, volumetric reductions in gray and white matter (WM) and some alterations of the WM microstructure. The goal of the current study was to characterize the WM microstructural differences in individuals with VCFS and unaffected siblings, and the correlation of WM microstructure with neuropsychological performance. We hypothesized that individuals with VCFS would have decreased indices …


Velo-Cardio-Facial Syndrome, Doron Gothelf, Amos Frisch, Elena Michaelovsky, Abraham Weizman, Robert Shprintzen Dec 2015

Velo-Cardio-Facial Syndrome, Doron Gothelf, Amos Frisch, Elena Michaelovsky, Abraham Weizman, Robert Shprintzen

Robert J. Shprintzen

Velocardiofacial syndrome (VCFS), also known as DiGeorge, conotruncal anomaly face, and Cayler syndromes, is caused by a microdeletion in the long arm of Chromosome 22. We review the history of the syndrome from the first clinical reports almost half a century ago to the current intriguing molecular findings associating genes from the microdeletion region and the physical and neuropsychiatric phenotype of the syndrome. Velocardiofacial syndrome has a wide spectrum of more than 200 physical manifestations including palate and cardiac anomalies. Yet, the most challenging manifestations of VCFS are the learning disabilities and neuropsychiatric disorders. As VCFS is relatively common and …


Genomic Disorders On Chromosome 22, Shihui Yu, William Graf, Robert Shprintzen Dec 2015

Genomic Disorders On Chromosome 22, Shihui Yu, William Graf, Robert Shprintzen

Robert J. Shprintzen

Purpose of review: Chromosome 22, the first human chromosome to be completely sequenced, is prone to genomic alterations. Copy-number variants (CNVs) are common because of an enrichment of low-copy repeat sequences that precipitate a high frequency of nonallelic homologous misalignments and unequal recombination during meiosis. Among these is one of the most common multiple anomaly syndromes in humans and the most common microdeletion syndrome, velocardiofacial syndrome (VCFS), also known as 22q11.2 deletion syndrome and DiGeorge syndrome. This review will focus on the recent literature dealing with both the molecular and clinical aspects of chromosome 22 genomic variations. Although the literature …


Genetic And Acute Cpeb1 Depletion Ameliorate Fragile X Pathophysiology, Tsuyoshi Udagawa, Natalie Farny, Mira Jakovcevski, Hanoch Kaphzan, Juan Alarcon, Shobha Anilkumar, Maria Ivshina, Jessica Hurt, Kentaro Nagaoka, Vijayalaxmi Nalavadi, Lori Lorenz, Gary Bassell, Schahram Akbarian, Sumantra Chattarji, Eric Klann, Joel Richter Dec 2015

Genetic And Acute Cpeb1 Depletion Ameliorate Fragile X Pathophysiology, Tsuyoshi Udagawa, Natalie Farny, Mira Jakovcevski, Hanoch Kaphzan, Juan Alarcon, Shobha Anilkumar, Maria Ivshina, Jessica Hurt, Kentaro Nagaoka, Vijayalaxmi Nalavadi, Lori Lorenz, Gary Bassell, Schahram Akbarian, Sumantra Chattarji, Eric Klann, Joel Richter

Natalie G. Farny

Fragile X syndrome (FXS), the most common cause of inherited mental retardation and autism, is caused by transcriptional silencing of FMR1, which encodes the translational repressor fragile X mental retardation protein (FMRP). FMRP and cytoplasmic polyadenylation element-binding protein (CPEB), an activator of translation, are present in neuronal dendrites, are predicted to bind many of the same mRNAs and may mediate a translational homeostasis that, when imbalanced, results in FXS. Consistent with this possibility, Fmr1(-/y); Cpeb1(-/-) double-knockout mice displayed amelioration of biochemical, morphological, electrophysiological and behavioral phenotypes associated with FXS. Acute depletion of CPEB1 in the hippocampus of adult Fmr1(-/y) mice …


Fgf2-Induced Effects On Transcriptome Associated With Regeneration Competence In Adult Human Fibroblasts, Olga Kashpur, David Lapointe, Sakthikumar Ambady, Elizabeth Ryder, Tanja Dominko Dec 2015

Fgf2-Induced Effects On Transcriptome Associated With Regeneration Competence In Adult Human Fibroblasts, Olga Kashpur, David Lapointe, Sakthikumar Ambady, Elizabeth Ryder, Tanja Dominko

Sakthikumar Ambady

BACKGROUND: Adult human fibroblasts grown in low oxygen and with FGF2 supplementation have the capacity to tip the healing outcome of skeletal muscle injury - by favoring regeneration response in vivo over scar formation. Here, we compare the transcriptomes of control adult human dermal fibroblasts and induced regeneration-competent (iRC) fibroblasts to identify transcriptional changes that may be related to their regeneration competence. RESULTS: We identified a unique gene-expression profile that characterizes FGF2-induced iRC fibroblast phenotype. Significantly differentially expressed genes due to FGF2 treatment were identified and analyzed to determine overrepresented Gene Ontology terms. Genes belonging to extracellular matrix components, adhesion …


Early Seed Development Responses In Cereals Under Environmental Stresses, Kevin Begcy Nov 2015

Early Seed Development Responses In Cereals Under Environmental Stresses, Kevin Begcy

Kevin Begcy

Plants are influenced by a large number of environmental factors. The search for higher yields at lower costs requires detailed knowledge of physiology, biochemistry, molecular and genetic level of plants, in order to optimize the relationship between different factors of production for maximum performance. Reproductive development has been demonstrated to be especially highly sensitive to environmental stresses. Within environmental stresses, drought and heat stress are the major restrictors of food production worldwide. With decreasing supplies of freshwater, increase in average temperature and predictions for the increased frequency of extreme precipitation events, there is a critical need for developing crops that …


Density, Species, And Size Distribution Of Groupers (Serranidae) In Three Habitats At Elbow Reef, Florida Keys, Robert Sluka, Mark Chiappone, Kathleen Sullivan-Sealey, Thomas Potts, Jose Levy, Emily Schmitt Lavin, Geoff Meester Nov 2015

Density, Species, And Size Distribution Of Groupers (Serranidae) In Three Habitats At Elbow Reef, Florida Keys, Robert Sluka, Mark Chiappone, Kathleen Sullivan-Sealey, Thomas Potts, Jose Levy, Emily Schmitt Lavin, Geoff Meester

Emily F Schmitt Lavin

We examined the density, size and species distribution of groupers in three habitats on an inshore-to-offshore transect across Elbow Reef, Florida Keys: high-relief spur-and-groove (4–9 m depth), relict spur-and-groove (10–20 m), and deep fore reef slope (21–30 m). Physical relief was greatest in the high-relief spur-and-groove (up to 3 m), lowest in the relict spur-and-groove habitat (<0.5–1 m), and intermediate in the deep fore reef slope habitat (1–1.5 m). Benthic coverage in the three habitats was dominated by algae (>30%). There were significant differences in the density, size, and species distribution of groupers among the three habitats. Graysby, Epinephelus cruentatus, was numerically dominant, constituting 82–91% of individual observed. Black grouper, Mycteroperca bonaci, and Nassau grouper, E. striatus, were more abundant in high …


Complete Genome Sequence Of Spiroplasma Turonicum Strain Tab4ct, A Parasite Of A Horse Fly, Haematopota Sp. (Diptera: Tabanidae)., Robert E. Davis, Jonathan Shao, Yan Zhao, Gail E. Gasparich, Brady J. Gaynor, Nicole Donofrio Nov 2015

Complete Genome Sequence Of Spiroplasma Turonicum Strain Tab4ct, A Parasite Of A Horse Fly, Haematopota Sp. (Diptera: Tabanidae)., Robert E. Davis, Jonathan Shao, Yan Zhao, Gail E. Gasparich, Brady J. Gaynor, Nicole Donofrio

Gail Gasparich

Spiroplasma turonicum was isolated from a Haematopota sp. fly in France. We report the nucleotide sequence of the circular chromosome of strain Tab4c(T). The genome information will facilitate evolutionary studies of spiroplasmas, including symbionts of insects and ticks and pathogens of plants, insects, crustaceans, and humans.


Evaluation Of Plant Growth Regulator, Immunity And Dna Fingerprinting Of Biofield Energy Treated Mustard Seeds (Brassica Juncea), Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Sambhu Charan Mondal, Snehasis Jana Nov 2015

Evaluation Of Plant Growth Regulator, Immunity And Dna Fingerprinting Of Biofield Energy Treated Mustard Seeds (Brassica Juncea), Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Sambhu Charan Mondal, Snehasis Jana

Mahendra Kumar Trivedi

Among the oilseeds grown around the world, mustard is one of the important crop worldwide due to its wide adaptability and high yielding capacity. Owing to the importance of its utilities as condiment, cooking oil and some medical aids, the demand for its seed production is too high. The present study was carried out to evaluate the impact of Mr. Trivedi’s biofield energy treatment on mustard (Brassica juncea) for its growth-germination of seedling, glutathione (GSH) content in leaves, indole acetic acid (IAA) content in shoots and roots and DNA polymorphism by random amplified polymorphic-DNA (RAPD). The sample of B. juncea …


Phenotyping And Genotyping Characterization Of Proteus Vulgaris After Biofield Treatment, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Sambhu Charan Mondal, Snehasis Jana Nov 2015

Phenotyping And Genotyping Characterization Of Proteus Vulgaris After Biofield Treatment, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Sambhu Charan Mondal, Snehasis Jana

Mahendra Kumar Trivedi

Proteus vulgaris (P. vulgaris) is widespread in nature, mainly found in flora of human gastrointestinal tract. The current study was attempted to investigate the effects of Mr. Trivedi’s biofield treatment on lyophilized as well as revived state of P. vulgaris for antimicrobial susceptibility pattern, biochemical characteristics, and biotype. P. vulgaris cells were procured from Micro BioLogics Inc., USA, in sealed pack bearing the American Type Culture Collection (ATCC 33420) number and stored according to the recommended storage protocol until needed for experiments. Lyophilized vial of ATCC strain of P. vulgaris were divided in two parts, Gr. I: control and Gr. …


Rna Recognition By The Caenorhabditis Elegans Oocyte Maturation Determinant Oma-1, Ebru Kaymak, Sean Ryder Oct 2015

Rna Recognition By The Caenorhabditis Elegans Oocyte Maturation Determinant Oma-1, Ebru Kaymak, Sean Ryder

Sean P. Ryder

Maternally supplied mRNAs encode proteins that pattern early embryos in many species. In the nematode Caenorhabditis elegans, a suite of RNA-binding proteins regulates expression of maternal mRNAs during oogenesis, the oocyte to embryo transition, and early embryogenesis. To understand how these RNA-binding proteins contribute to development, it is necessary to determine how they select specific mRNA targets for regulation. OMA-1 and OMA-2 are redundant proteins required for oocyte maturation--an essential part of meiosis that prepares oocytes for fertilization. Both proteins have CCCH type tandem zinc finger RNA-binding domains. Here, we define the RNA binding specificity of OMA-1 and demonstrate that …


Complete Genome Sequence Of Spiroplasma Kunkelii Strain Cr2-3x, Causal Agent Of Corn Stunt Disease In Zea Mays L., Robert E. Davis, Jonathan Shao, Ellen L. Dally, Yan Zhao, Gail E. Gasparich, Brady J. Gaynor, John C. Athey, Nigel A. Harrison, Nicole Donofrio Oct 2015

Complete Genome Sequence Of Spiroplasma Kunkelii Strain Cr2-3x, Causal Agent Of Corn Stunt Disease In Zea Mays L., Robert E. Davis, Jonathan Shao, Ellen L. Dally, Yan Zhao, Gail E. Gasparich, Brady J. Gaynor, John C. Athey, Nigel A. Harrison, Nicole Donofrio

Gail Gasparich

Spiroplasma kunkelii causes corn stunt disease of Zea mays L. in the Americas. Here, we report the nucleotide sequence of the 1,463,926-bp circular chromosome and four plasmids of strain CR2-3x. This information will facilitate studies of Spiroplasma pathogenicity and evolutionary adaptations to transkingdom parasitism in plants and insect vectors.


Biodistribution And Function Of Extracellular Mirna-155 In Mice, Shashi Bala, Timea Csak, Fatemeh Momen-Heravi, Dora Lippai, Karen Kodys, Donna Catalano, Abhishek Satishchandran, Victor R. Ambros, Gyongyi Szabo Oct 2015

Biodistribution And Function Of Extracellular Mirna-155 In Mice, Shashi Bala, Timea Csak, Fatemeh Momen-Heravi, Dora Lippai, Karen Kodys, Donna Catalano, Abhishek Satishchandran, Victor R. Ambros, Gyongyi Szabo

Gyongyi Szabo

Circulating miRNAs can be found in extracellular vesicles (EV) and could be involved in intercellular communication. Here, we report the biodistribution of EV associated miR-155 using miR-155 KO mouse model. Administration of exosomes loaded with synthetic miR-155 mimic into miR-155 KO mice resulted in a rapid accumulation and clearance of miR-155 in the plasma with subsequent distribution in the liver, adipose tissue, lung, muscle and kidney (highest to lowest, respectively). miR-155 expression was detected in isolated hepatocytes and liver mononuclear cells of recipient KO mice suggesting its cellular uptake. In vitro, exosome-mediated restoration of miR-155 in Kupffer cells from miR-155 …


Caenorhabditis Elegans Alg-1 Antimorphic Mutations Uncover Functions For Argonaute In Microrna Guide Strand Selection And Passenger Strand Disposal, Anna Y. Zinovyeva, Isana Veksler-Lublinsky, Ajay A. Vashisht, James A. Wohlschlegel, Victor R. Ambros Oct 2015

Caenorhabditis Elegans Alg-1 Antimorphic Mutations Uncover Functions For Argonaute In Microrna Guide Strand Selection And Passenger Strand Disposal, Anna Y. Zinovyeva, Isana Veksler-Lublinsky, Ajay A. Vashisht, James A. Wohlschlegel, Victor R. Ambros

Victor R. Ambros

MicroRNAs are regulators of gene expression whose functions are critical for normal development and physiology. We have previously characterized mutations in a Caenorhabditis elegans microRNA-specific Argonaute ALG-1 (Argonaute-like gene) that are antimorphic [alg-1(anti)]. alg-1(anti) mutants have dramatically stronger microRNA-related phenotypes than animals with a complete loss of ALG-1. ALG-1(anti) miRISC (microRNA induced silencing complex) fails to undergo a functional transition from microRNA processing to target repression. To better understand this transition, we characterized the small RNA and protein populations associated with ALG-1(anti) complexes in vivo. We extensively characterized proteins associated with wild-type and mutant ALG-1 and found that the mutant …


Robust Distal Tip Cell Pathfinding In The Face Of Temperature Stress Is Ensured By Two Conserved Micrornas In Caenorhabditis Elegans, Samantha L. Burke, Molly Hammell, Victor R. Ambros Oct 2015

Robust Distal Tip Cell Pathfinding In The Face Of Temperature Stress Is Ensured By Two Conserved Micrornas In Caenorhabditis Elegans, Samantha L. Burke, Molly Hammell, Victor R. Ambros

Victor R. Ambros

Biological robustness, the ability of an organism to maintain a steady-state output as genetic or environmental inputs change, is critical for proper development. MicroRNAs have been implicated in biological robustness mechanisms through their post-transcriptional regulation of genes and gene networks. Previous research has illustrated examples of microRNAs promoting robustness as part of feedback loops and genetic switches and by buffering noisy gene expression resulting from environmental and/or internal changes. Here we show that the evolutionarily conserved microRNAs mir-34 and mir-83 (homolog of mammalian mir-29) contribute to the robust migration pattern of the distal tip cells in Caenorhabditis elegans by specifically …


Biodistribution And Function Of Extracellular Mirna-155 In Mice, Shashi Bala, Timea Csak, Fatemeh Momen-Heravi, Dora Lippai, Karen Kodys, Donna Catalano, Abhishek Satishchandran, Victor R. Ambros, Gyongyi Szabo Oct 2015

Biodistribution And Function Of Extracellular Mirna-155 In Mice, Shashi Bala, Timea Csak, Fatemeh Momen-Heravi, Dora Lippai, Karen Kodys, Donna Catalano, Abhishek Satishchandran, Victor R. Ambros, Gyongyi Szabo

Victor R. Ambros

Circulating miRNAs can be found in extracellular vesicles (EV) and could be involved in intercellular communication. Here, we report the biodistribution of EV associated miR-155 using miR-155 KO mouse model. Administration of exosomes loaded with synthetic miR-155 mimic into miR-155 KO mice resulted in a rapid accumulation and clearance of miR-155 in the plasma with subsequent distribution in the liver, adipose tissue, lung, muscle and kidney (highest to lowest, respectively). miR-155 expression was detected in isolated hepatocytes and liver mononuclear cells of recipient KO mice suggesting its cellular uptake. In vitro, exosome-mediated restoration of miR-155 in Kupffer cells from miR-155 …


Inhibiting Mirna In Caenorhabditis Elegans Using A Potent And Selective Antisense Reagent, Genhua Zheng, Victor R. Ambros, Wen-Hong Li Oct 2015

Inhibiting Mirna In Caenorhabditis Elegans Using A Potent And Selective Antisense Reagent, Genhua Zheng, Victor R. Ambros, Wen-Hong Li

Victor R. Ambros

BACKGROUND: Antisense reagents can serve as efficient and versatile tools for studying gene function by inhibiting nucleic acids in vivo. Antisense reagents have particular utility for the experimental manipulation of the activity of microRNAs (miRNAs), which are involved in the regulation of diverse developmental and physiological pathways in animals. Even in traditional genetic systems, such as the nematode Caenorhabditis elegans, antisense reagents can provide experimental strategies complementary to mutational approaches. Presently no antisense reagents are available for inhibiting miRNAs in the nematode C. elegans. RESULTS: We have developed a new class of fluorescently labelled antisense reagents to inhibit miRNAs in …


Control Of Stem Cell Self-Renewal And Differentiation By The Heterochronic Genes And The Cellular Asymmetry Machinery In Caenorhabditis Elegans, Omid F. Harandi, Victor Ambros Oct 2015

Control Of Stem Cell Self-Renewal And Differentiation By The Heterochronic Genes And The Cellular Asymmetry Machinery In Caenorhabditis Elegans, Omid F. Harandi, Victor Ambros

Victor R. Ambros

Transitions between asymmetric (self-renewing) and symmetric (proliferative) cell divisions are robustly regulated in the context of normal development and tissue homeostasis. To genetically assess the regulation of these transitions, we used the postembryonic epithelial stem (seam) cell lineages of Caenorhabditis elegans. In these lineages, the timing of these transitions is regulated by the evolutionarily conserved heterochronic pathway, whereas cell division asymmetry is conferred by a pathway consisting of Wnt (Wingless) pathway components, including posterior pharynx defect (POP-1)/TCF, APC related/adenomatosis polyposis coli (APR-1)/APC, and LIT-1/NLK (loss of intestine/Nemo-like kinase). Here we explore the genetic regulatory mechanisms underlying stage-specific transitions between self-renewing …


The Decapping Scavenger Enzyme Dcs-1 Controls Microrna Levels In Caenorhabditis Elegans, Gabriel Bosse, Stefan Ruegger, Maria Ow, Alejandro Vasquez-Rifo, Evelyne Rondeau, Victor Ambros, Helge Grosshans, Martin Simard Oct 2015

The Decapping Scavenger Enzyme Dcs-1 Controls Microrna Levels In Caenorhabditis Elegans, Gabriel Bosse, Stefan Ruegger, Maria Ow, Alejandro Vasquez-Rifo, Evelyne Rondeau, Victor Ambros, Helge Grosshans, Martin Simard

Victor R. Ambros

In metazoans, microRNAs play a critical role in the posttranscriptional regulation of genes required for cell proliferation and differentiation. MicroRNAs themselves are regulated by a multitude of mechanisms influencing their transcription and posttranscriptional maturation. However, there is only sparse knowledge on pathways regulating the mature, functional form of microRNA. Here, we uncover the implication of the decapping scavenger protein DCS-1 in the control of microRNA turnover. In Caenorhabditis elegans, mutations in dcs-1 increase the levels of functional microRNAs. We demonstrate that DCS-1 interacts with the exonuclease XRN-1 to promote microRNA degradation in an independent manner from its known decapping scavenger …


Developmental Decline In Neuronal Regeneration By The Progressive Change Of Two Intrinsic Timers, Yan Zou, Hui Chiu, Anna Zinovyeva, Victor Ambros, Chiou-Fen Chuang, Chieh Chang Oct 2015

Developmental Decline In Neuronal Regeneration By The Progressive Change Of Two Intrinsic Timers, Yan Zou, Hui Chiu, Anna Zinovyeva, Victor Ambros, Chiou-Fen Chuang, Chieh Chang

Victor R. Ambros

Like mammalian neurons, Caenorhabditis elegans neurons lose axon regeneration ability as they age, but it is not known why. Here, we report that let-7 contributes to a developmental decline in anterior ventral microtubule (AVM) axon regeneration. In older AVM axons, let-7 inhibits regeneration by down-regulating LIN-41, an important AVM axon regeneration-promoting factor. Whereas let-7 inhibits lin-41 expression in older neurons through the lin-41 3' untranslated region, lin-41 inhibits let-7 expression in younger neurons through Argonaute ALG-1. This reciprocal inhibition ensures that axon regeneration is inhibited only in older neurons. These findings show that a let-7-lin-41 regulatory circuit, which was previously …


The Evolution Of Our Thinking About Micrornas, Victor Ambros Oct 2015

The Evolution Of Our Thinking About Micrornas, Victor Ambros

Victor R. Ambros

Our appreciation of the significance of microRNAs to biology at large continues to be an evolving process.


Victor Ambros: The Broad Scope Of Micrornas. Interview By Caitlin Sedwick, Victor R. Ambros Oct 2015

Victor Ambros: The Broad Scope Of Micrornas. Interview By Caitlin Sedwick, Victor R. Ambros

Victor R. Ambros

Interview with Victor Ambros, who studies how microRNAs impact development.


Mutations In Conserved Residues Of The C. Elegans Microrna Argonaute Alg-1 Identify Separable Functions In Alg-1 Mirisc Loading And Target Repression, Anna Y. Zinovyeva, Samir Bouasker, Martin J. Simard, Christopher M. Hammell, Victor R. Ambros Oct 2015

Mutations In Conserved Residues Of The C. Elegans Microrna Argonaute Alg-1 Identify Separable Functions In Alg-1 Mirisc Loading And Target Repression, Anna Y. Zinovyeva, Samir Bouasker, Martin J. Simard, Christopher M. Hammell, Victor R. Ambros

Victor R. Ambros

microRNAs function in diverse developmental and physiological processes by regulating target gene expression at the post-transcriptional level. ALG-1 is one of two Caenorhabditis elegans Argonautes (ALG-1 and ALG-2) that together are essential for microRNA biogenesis and function. Here, we report the identification of novel antimorphic (anti) alleles of ALG-1 as suppressors of lin-28(lf) precocious developmental phenotypes. The alg-1(anti) mutations broadly impair the function of many microRNAs and cause dosage-dependent phenotypes that are more severe than the complete loss of ALG-1. ALG-1(anti) mutant proteins are competent for promoting Dicer cleavage of microRNA precursors and for associating with and stabilizing microRNAs. However, …


The Developmental Timing Regulator Hbl-1 Modulates The Dauer Formation Decision In Caenorhabditis Elegans, Xantha Karp, Victor Ambros Oct 2015

The Developmental Timing Regulator Hbl-1 Modulates The Dauer Formation Decision In Caenorhabditis Elegans, Xantha Karp, Victor Ambros

Victor R. Ambros

Animals developing in the wild encounter a range of environmental conditions, and so developmental mechanisms have evolved that can accommodate different environmental contingencies. Harsh environmental conditions cause Caenorhabditis elegans larvae to arrest as stress-resistant "dauer" larvae after the second larval stage (L2), thereby indefinitely postponing L3 cell fates. HBL-1 is a key transcriptional regulator of L2 vs. L3 cell fate. Through the analysis of genetic interactions between mutations of hbl-1 and of genes encoding regulators of dauer larva formation, we find that hbl-1 can also modulate the dauer formation decision in a complex manner. We propose that dynamic interactions between …


Mir-14 Regulates Autophagy During Developmental Cell Death By Targeting Ip3-Kinase 2, Charles Nelson, Victor Ambros, Eric Baehrecke Oct 2015

Mir-14 Regulates Autophagy During Developmental Cell Death By Targeting Ip3-Kinase 2, Charles Nelson, Victor Ambros, Eric Baehrecke

Victor R. Ambros

Macroautophagy (autophagy) is a lysosome-dependent degradation process that has been implicated in age-associated diseases. Autophagy is involved in both cell survival and cell death, but little is known about the mechanisms that distinguish its use during these distinct cell fates. Here, we identify the microRNA miR-14 as being both necessary and sufficient for autophagy during developmentally regulated cell death in Drosophila. Loss of miR-14 prevented induction of autophagy during salivary gland cell death, but had no effect on starvation-induced autophagy in the fat body. Moreover, misexpression of miR-14 was sufficient to prematurely induce autophagy in salivary glands, but not in …


Circulating Micrornas In Cardiovascular Disease, David Mcmanus, Victor Ambros Oct 2015

Circulating Micrornas In Cardiovascular Disease, David Mcmanus, Victor Ambros

Victor R. Ambros

Comment on: Transcoronary concentration gradients of circulating microRNAs. [Circulation. 2011]


Plasma Micrornas Are Associated With Atrial Fibrillation (The Mirhythm Study) And Change After Catheter-Ablation, David D. Mcmanus, Kahraman Tanriverdi, Honghuang Lin, Nada Esa, Menhel Kinno, Rosalind Lee, Divakar Mandapati, Stanley Tam, Patrick T. Ellinor, John F. Keaney, Emelia J. Benjamin, Victor R. Ambros, Jane E. Freedman Oct 2015

Plasma Micrornas Are Associated With Atrial Fibrillation (The Mirhythm Study) And Change After Catheter-Ablation, David D. Mcmanus, Kahraman Tanriverdi, Honghuang Lin, Nada Esa, Menhel Kinno, Rosalind Lee, Divakar Mandapati, Stanley Tam, Patrick T. Ellinor, John F. Keaney, Emelia J. Benjamin, Victor R. Ambros, Jane E. Freedman

Victor R. Ambros

Background: Atrial fibrillation (AF) is the most common dysrhythmia in the U.S. and Europe. Few biomarkers exist to identify individuals at risk for AF. Cardiac microRNAs (miRNAs) have been implicated in susceptibility to AF and are detectable in the circulation. Nevertheless, data are limited on how circulating levels of miRNAs relate to AF or change over time after catheter- ablation. Methods: In 211 miRhythm participants (112 with paroxysmal or persistent AF; 99 without AF), we quantified plasma expression of 86 miRNAs associated with cardiac remodeling or disease by high-throughput quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR). We used qRT-PCR to examine …


Micrornas And Developmental Timing, Victor Ambros Oct 2015

Micrornas And Developmental Timing, Victor Ambros

Victor R. Ambros

MicroRNAs regulate temporal transitions in gene expression associated with cell fate progression and differentiation throughout animal development. Genetic analysis of developmental timing in the nematode Caenorhabditis elegans identified two evolutionarily conserved microRNAs, lin-4/mir-125 and let-7, that regulate cell fate progression and differentiation in C. elegans cell lineages. MicroRNAs perform analogous developmental timing functions in other animals, including mammals. By regulating cell fate choices and transitions between pluripotency and differentiation, microRNAs help to orchestrate developmental events throughout the developing animal, and to play tissue homeostasis roles important for disease, including cancer.