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1.
Nucleic Acids Res ; 38(16): 5327-35, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20421205

RESUMEN

N(6)-Methyladenosine (m(6)A) is a modified base present in the mRNA of all higher eukaryotes and in Saccharomyces cerevisiae, where there is an increase in m(6)A levels during sporulation. The methyltransferase, Ime4, is responsible for this modification and has a role in the initiation of meiosis. However, neither the function, nor the extent of distribution of this nucleotide modification is established. We demonstrate that in S. cerevisiae, substantial levels of internal adenosine methylation are present in the GpA context in mRNA from sporulating cells, which is consistent with the preferred methylation consensus of higher eukaryotes. Based upon our quantification data, every second transcript could contain one m(6)A during meiosis. As methylation is distributed across all mRNA size ranges, it is likely that m(6)A is not limited to a small population of messages. We developed a new antibody based method for identifying m(6)A containing messages, and using this method the transcripts of three key, early regulators of meiosis, IME1, IME2 and IME4 itself, were identified as being methylated. The position of m(6)A in IME2 was narrowed down to a region in the 3'-end. Methylation of these and other targets suggests mechanisms by which IME4 could control developmental choices leading to meiosis.


Asunto(s)
Adenosina/análogos & derivados , ARN Mensajero/metabolismo , Saccharomyces cerevisiae/genética , Adenosina/análisis , Inmunoprecipitación , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Metilación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Mensajero/química , ARN Mensajero/aislamiento & purificación , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiología , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Esporas Fúngicas/fisiología
2.
Nat Commun ; 11(1): 1816, 2020 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-32286330

RESUMEN

Protein biopharmaceuticals are highly successful, but their utility is compromised by their propensity to aggregate during manufacture and storage. As aggregation can be triggered by non-native states, whose population is not necessarily related to thermodynamic stability, prediction of poorly-behaving biologics is difficult, and searching for sequences with desired properties is labour-intensive and time-consuming. Here we show that an assay in the periplasm of E. coli linking aggregation directly to antibiotic resistance acts as a sensor for the innate (un-accelerated) aggregation of antibody fragments. Using this assay as a directed evolution screen, we demonstrate the generation of aggregation resistant scFv sequences when reformatted as IgGs. This powerful tool can thus screen and evolve 'manufacturable' biopharmaceuticals early in industrial development. By comparing the mutational profiles of three different immunoglobulin scaffolds, we show the applicability of this method to investigate protein aggregation mechanisms important to both industrial manufacture and amyloid disease.


Asunto(s)
Agregado de Proteínas , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Regiones Determinantes de Complementariedad/química , Escherichia coli/metabolismo , Humanos , Inmunoglobulina G/química , Viabilidad Microbiana , Mutación/genética , Anticuerpos de Cadena Única/química , beta-Lactamasas/química
3.
Pain ; 160(9): 1989-2003, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31045747

RESUMEN

P2X4 is a ligand-gated ion channel implicated in neuropathic pain. Drug discovery efforts targeting P2X4 have been unsuccessful largely because of the difficulty in engineering specificity and selectivity. Here, we describe for the first time the generation of a panel of diverse monoclonal antibodies (mAbs) to human and mouse P2X4, capable of both positive and negative modulation of channel function. The affinity-optimised anti-P2X4 mAb IgG#151-LO showed exquisite selectivity for human P2X4 and induced potent and complete block of P2X4 currents. Site-directed mutagenesis of P2X4 revealed the head domain as a key interaction site for inhibitory mAbs. Inhibition of spinal P2X4 either by intrathecal delivery of an anti-P2X4 mAb or by systemic delivery of an anti-P2X4 bispecific mAb with enhanced blood-spinal cord barrier permeability produced long-lasting (>7 days) analgesia in a mouse model of neuropathic pain. We therefore propose that inhibitory mAbs binding the head domain of P2X4 have therapeutic potential for the treatment of neuropathic pain.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/metabolismo , Neuralgia/metabolismo , Neuralgia/prevención & control , Receptores Purinérgicos P2X4/metabolismo , Animales , Células Cultivadas , Femenino , Células HEK293 , Humanos , Inyecciones Espinales , Ratones , Ratones Endogámicos C57BL , Unión Proteica/fisiología , Antagonistas del Receptor Purinérgico P2X/administración & dosificación , Antagonistas del Receptor Purinérgico P2X/metabolismo , Ratas , Ratas Sprague-Dawley
4.
J Sch Health ; 76(3): 93-7, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16475984

RESUMEN

Schools are increasingly expected to address the needs of gay, lesbian, bisexual, and transgender students. However, the controversial nature of sexual orientation programs and policies makes this a politically sensitive undertaking. This empirical study analyzes the extent to which public school districts across the United States have implemented policy recommendations and describes, according to 4 theoretical policy models, factors that influence their ability to do so. The survey found that most districts have not institutionalized recommended policies or programs. Recommendations for school health professionals based on factors found to be significantly associated with the implementation of programs are discussed.


Asunto(s)
Política , Instituciones Académicas , Conducta Sexual , Adolescente , Investigación Empírica , Humanos , Estados Unidos
5.
J Homosex ; 42(4): 145-68, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12243482

RESUMEN

In what has sometimes provoked a "culture war" over America's schools, gays and lesbians have sought an expanded voice in the making of education policy. This paper explores the factors that promote gay representation on school boards, how this variable in turn influences gay representation in both administrative and teaching positions, and how all three forms of gay representation relate to school board policies regarding sexual orientation education. Three of the four models drawn from the social movement literature help to explain gay school board representation. In a manner similar to other minority groups, gay representation on school boards directly or indirectly promotes the appointment of gays to administrative and teaching positions and the adoption of policies that address the problems faced by gay and lesbian students in the public schools.


Asunto(s)
Educación , Homosexualidad Femenina , Homosexualidad Masculina , Política , Femenino , Humanos , Gobierno Local , Masculino , Prejuicio , Política Pública , Instituciones Académicas , Estados Unidos
6.
Sci Rep ; 1: 126, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22355643

RESUMEN

A method is described for the detection of certain nucleotide modifications adjacent to the 5' 7-methyl guanosine cap of mRNAs from individual genes. The method quantitatively measures the relative abundance of 2'-O-methyl and N(6),2'-O-dimethyladenosine, two of the most common modifications. In order to identify and quantitatify the amounts of N(6),2'-O-dimethyladenosine, a novel method for the synthesis of modified adenosine phosphoramidites was developed. This method is a one step synthesis and the product can directly be used for the production of N(6),2'-O-dimethyladenosine containing RNA oligonucleotides. The nature of the cap-adjacent nucleotides were shown to be characteristic for mRNAs from individual genes transcribed in liver and testis.


Asunto(s)
Análogos de Caperuza de ARN/síntesis química , ARN Mensajero/química , ARN Mensajero/metabolismo , Adenosina/química , Animales , Secuencia de Bases , Cromatografía en Capa Delgada , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Análogos de Caperuza de ARN/química , Análogos de Caperuza de ARN/genética , ARN Mensajero/genética , Testículo/metabolismo
7.
Plant Cell ; 20(5): 1278-88, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18505803

RESUMEN

N6-Methyladenosine is a ubiquitous modification identified in the mRNA of numerous eukaryotes, where it is present within both coding and noncoding regions. However, this base modification does not alter the coding capacity, and its biological significance remains unclear. We show that Arabidopsis thaliana mRNA contains N6-methyladenosine at levels similar to those previously reported for animal cells. We further show that inactivation of the Arabidopsis ortholog of the yeast and human mRNA adenosine methylase (MTA) results in failure of the developing embryo to progress past the globular stage. We also demonstrate that the arrested seeds are deficient in mRNAs containing N6-methyladenosine. Expression of MTA is strongly associated with dividing tissues, particularly reproductive organs, shoot meristems, and emerging lateral roots. Finally, we show that MTA interacts in vitro and in vivo with At FIP37, a homolog of the Drosophila protein FEMALE LETHAL2D and of human WILMS' TUMOUR1-ASSOCIATING PROTEIN. The results reported here provide direct evidence for an essential function for N6-methyladenosine in a multicellular eukaryote, and the interaction with At FIP37 suggests possible RNA processing events that might be regulated or altered by this base modification.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Proteínas Portadoras/metabolismo , Metiltransferasas/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Cromatografía en Capa Delgada , Flores/enzimología , Flores/genética , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Prueba de Complementación Genética , Inmunoprecipitación , Metiltransferasas/genética , Datos de Secuencia Molecular , Hojas de la Planta/enzimología , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Raíces de Plantas/enzimología , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Unión Proteica , ARN Mensajero/metabolismo , Proteínas de Unión al ARN , Técnicas del Sistema de Dos Híbridos
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