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1.
PLoS One ; 17(7): e0269341, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35834506

RESUMO

BACKGROUND: The menstrual needs of girls and women are important to health, education, and well-being. Unmet need and harm from poor menstrual health in low-and- middle-income countries have been documented, but with little empirical research undertaken in high income countries. Continuing austerity in the UK suggests menstruators are likely more vulnerable to 'period poverty' than previously, with the COVID-19 pandemic assumed to exacerbate the situation. AIM: To explore the menstrual experiences and perceptions of women in the UK who are living under circumstances of deprivation, alongside views of staff working in organisations supporting these women, to understand whether women's menstrual needs are met. METHODS: A qualitative study was conducted in an inner-city in NW England. Three focus group discussions and 14 in-depth interviews were conducted across three study sites supporting impoverished women. Data was analysed thematically. RESULTS: Themes were: reflections on menstruation; affordability of products; access to public facilities; organisational support; potential solutions. Many women perceived menstruation as a burden in three aspects: physical discomfort and pain; psychological anxiety; and shame and stigma. Managing menstruation was difficult due to cost relative to low incomes, with food, heating and lighting prioritised, leaving women improvising with materials or wearing products for longer than desired. Most suggested that products should be free, often remarking if men required similar items this would happen. Most women were unaware supporting organisations provided free products. Staff felt the small range of products offered did not meet client needs and were ill-prepared to have conversations on products and clients' menstrual needs. CONCLUSION: Impoverished women lack the necessary resources to manage their menses well which negatively impacts their health and brings stress, embarrassment, and shame. Support, including access to free products, is needed at both local and national level to help impoverished women manage their menstrual hygiene.


Assuntos
COVID-19 , Menstruação , COVID-19/epidemiologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Higiene , Masculino , Menstruação/psicologia , Pandemias , Pobreza
2.
J Biol Chem ; 287(39): 32535-45, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22854966

RESUMO

The Elongator complex is composed of 6 subunits (Elp1-Elp6) and promotes RNAPII transcript elongation through histone acetylation in the nucleus as well as tRNA modification in the cytoplasm. This acetyltransferase complex directly or indirectly regulates numerous biological processes ranging from exocytosis and resistance to heat shock in yeast to cell migration and neuronal differentiation in higher eukaryotes. The identity of human ELP1 through ELP4 has been reported but human ELP5 and ELP6 have remained uncharacterized. Here, we report that DERP6 (ELP5) and C3ORF75 (ELP6) encode these subunits of human Elongator. We further investigated the importance and function of these two subunits by a combination of biochemical analysis and cellular assays. Our results show that DERP6/ELP5 is required for the integrity of Elongator and directly connects ELP3 to ELP4. Importantly, the migration and tumorigenicity of melanoma-derived cells are significantly decreased upon Elongator depletion through ELP1 or ELP3. Strikingly, DERP6/ELP5 and C3ORF75/ELP6-depleted melanoma cells have similar defects, further supporting the idea that DERP6/ELP5 and C3ORF75/ELP6 are essential for Elongator function. Together, our data identify DERP6/ELP5 and C3ORF75/ELP6 as key players for migration, invasion and tumorigenicity of melanoma cells, as integral subunits of Elongator.


Assuntos
Proteínas de Transporte/metabolismo , Movimento Celular , Melanoma/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas/metabolismo , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Deleção de Genes , Células HEK293 , Histona Acetiltransferases , Humanos , Melanoma/genética , Melanoma/patologia , Complexos Multiproteicos/genética , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Proteínas/genética , RNA Polimerase II/genética , RNA Polimerase II/metabolismo
3.
Mol Cell ; 42(3): 285-96, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21549307

RESUMO

Epigenetic marks such as posttranslational histone modifications specify the functional states of underlying DNA sequences, though how they are maintained after their disruption during DNA replication remains a critical question. We identify the mammalian SWI/SNF-like protein SMARCAD1 as a key factor required for the re-establishment of repressive chromatin. The ATPase activity of SMARCAD1 is necessary for global deacetylation of histones H3/H4. In this way, SMARCAD1 promotes methylation of H3K9, the establishment of heterochromatin, and faithful chromosome segregation. SMARCAD1 associates with transcriptional repressors including KAP1, histone deacetylases HDAC1/2 and the histone methyltransferase G9a/GLP and modulates the interaction of HDAC1 and KAP1 with heterochromatin. SMARCAD1 directly interacts with PCNA, a central component of the replication machinery, and is recruited to sites of DNA replication. Our findings suggest that chromatin remodeling by SMARCAD1 ensures that silenced loci, such as pericentric heterochromatin, are correctly perpetuated.


Assuntos
Cromatina/metabolismo , DNA Helicases/metabolismo , Replicação do DNA , Histonas/metabolismo , Acetilação , Adenosina Trifosfatases/metabolismo , Animais , Western Blotting , Linhagem Celular , Células Cultivadas , Cromatina/genética , DNA Helicases/genética , Regulação da Expressão Gênica , Células HEK293 , Células HeLa , Heterocromatina/genética , Heterocromatina/metabolismo , Histona Desacetilase 1/metabolismo , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Metilação , Camundongos , Células NIH 3T3 , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fase S
4.
Insect Biochem Mol Biol ; 38(1): 113-23, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18070670

RESUMO

Annotation of the recently determined genome sequence of the major dengue vector, Aedes aegypti, reveals an abundance of detoxification genes. Here, we report the presence of 235 members of the cytochrome P450, glutathione transferase and carboxy/cholinesterase families in Ae. aegypti. This gene count represents an increase of 58% and 36% compared with the fruitfly, Drosophila melanogaster, and the malaria mosquito, Anopheles gambiae, respectively. The expansion is not uniform within the gene families. Secure orthologs can be found across the insect species for enzymes that have presumed or proven biosynthetic or housekeeping roles. In contrast, subsets of these gene families that are associated with general xenobiotic detoxification, in particular the CYP6, CYP9 and alpha esterase families, have expanded in Ae. aegypti. In order to identify detoxification genes associated with resistance to insecticides we constructed an array containing unique oligonucleotide probes for these genes and compared their expression level in insecticide resistant and susceptible strains. Several candidate genes were identified with the majority belonging to two gene families, the CYP9 P450s and the Epsilon GSTs. This 'Ae. aegypti Detox Chip' will facilitate the implementation of insecticide resistance management strategies for arboviral control programmes.


Assuntos
Aedes/genética , Genoma de Inseto , Inativação Metabólica/genética , Resistência a Inseticidas/genética , Animais , Carboxilesterase/genética , Colinesterases/genética , Sistema Enzimático do Citocromo P-450/genética , Perfilação da Expressão Gênica , Glutationa Transferase/genética , Família Multigênica , Análise de Sequência com Séries de Oligonucleotídeos
5.
Mol Cell ; 22(4): 521-31, 2006 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-16713582

RESUMO

Mutations in IKBKAP, encoding a subunit of Elongator, cause familial dysautonomia (FD), a severe neurodevelopmental disease with complex clinical characteristics. Elongator was previously linked not only with transcriptional elongation and histone acetylation but also with other cellular processes. Here, we used RNA interference (RNAi) and fibroblasts from FD patients to identify Elongator target genes and study the role of Elongator in transcription. Strikingly, whereas Elongator is recruited to both target and nontarget genes, only target genes display histone H3 hypoacetylation and progressively lower RNAPII density through the coding region in FD cells. Interestingly, several target genes encode proteins implicated in cell motility. Indeed, characterization of IKAP/hELP1 RNAi cells, FD fibroblasts, and neuronal cell-derived cells uncovered defects in this cellular function upon Elongator depletion. These results indicate that defects in Elongator function affect transcriptional elongation of several genes and that the ensuing cell motility deficiencies may underlie the neuropathology of FD patients.


Assuntos
Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Disautonomia Familiar/etiologia , Proteínas de Transporte/antagonistas & inibidores , Linhagem Celular , Movimento Celular/genética , Movimento Celular/fisiologia , Disautonomia Familiar/genética , Disautonomia Familiar/metabolismo , Disautonomia Familiar/patologia , Regulação da Expressão Gênica , Células HeLa , Histonas/metabolismo , Humanos , Mutação , Interferência de RNA , RNA Polimerase II/metabolismo , Transcrição Gênica , Fatores de Elongação da Transcrição
7.
Cell Cycle ; 4(4): 543-6, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15753658

RESUMO

During DNA replication, chromatin states have to be accurately transmitted from the parental to the daughter strands for faithful epigenetic inheritance. Chromatin remodelling factors at the replication site are thought to be involved in this process. Recent work adds ATP-dependent nucleosome remodelling factors to this category of enzymes. The WICH complex, consisting of the ISWI-type ATPase SNF2H and the Williams Syndrome Transcription Factor (WSTF), binds to replication foci using PCNA, a key factor in DNA- and chromatin replication and DNA repair, as an interaction platform. Depletion of WSTF results in decreased chromatin accessibility, which is evident already in newly replicated DNA. This leads to heterochromatin formation on a global scale and a decrease in overall transcriptional activity. Here, we propose that WICH, by keeping nucleosomes mobile, provides access to the newly replicated DNA and may thereby create a window of opportunity after DNA replication for rebinding of factors that maintain the epigenetic state, and thus prevents aberrant heterochromatin formation. Our model may provide an explanation for the long-standing observation of a delay in chromatin "maturation" on newly replicated DNA, by connecting this delay with the action of PCNA-bound WSTF-ISWI, and highlights chromatin remodeling shortly after DNA replication as a critical point for regulation.


Assuntos
Adenosina Trifosfatases/fisiologia , Cromatina/química , Regulação da Expressão Gênica , Fatores de Transcrição/fisiologia , Animais , Sítios de Ligação , Ciclo Celular , DNA/química , Replicação do DNA , Epigênese Genética , Heterocromatina/química , Humanos , Modelos Biológicos , Nucleossomos/química , Ligação Proteica
8.
Biochem J ; 387(Pt 3): 879-88, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15631620

RESUMO

Epsilon class GSTs (glutathione transferases) are expressed at higher levels in Anopheles gambiae mosquitoes that are resistant to DDT [1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane] than in insecticide-susceptible individuals. At least one of the eight Epsilon GSTs in this species, GSTe2, efficiently metabolizes DDT to DDE [1,1-dichloro-2,2-bis-(p-chlorophenyl)ethane]. In the present study, we investigated the factors regulating expression of this class of GSTs. The activity of the promoter regions of GSTe2 and GSTe3 were compared between resistant and susceptible strains by transfecting recombinant reporter constructs into an A. gambiae cell line. The GSTe2 promoter from the resistant strain exhibited 2.8-fold higher activity than that of the susceptible strain. Six polymorphic sites were identified in the 352 bp sequence immediately upstream of GSTe2. Among these, a 2 bp adenosine indel (insertion/deletion) was found to have the greatest effect on determining promoter activity. The activity of the GSTe3 promoter was elevated to a lesser degree in the DDT-resistant strain (1.3-fold). The role of putative transcription-factor-binding sites in controlling promoter activity was investigated by sequentially deleting the promoter constructs. Several putative transcription-factor-binding sites that are responsive to oxidative stress were present within the core promoters of these GSTs, hence the effect of H2O2 exposure on the transcription of the Epsilon GSTs was investigated. In the DDT-resistant strain, expression of GSTe1, GSTe2 and GSTe3 was significantly increased by a 1-h exposure to H2O2, whereas, in the susceptible strain, only GSTe3 expression responded to this treatment.


Assuntos
Anopheles/enzimologia , Glutationa Transferase/biossíntese , Glutationa Transferase/genética , Regiões Promotoras Genéticas/fisiologia , Animais , Anopheles/efeitos dos fármacos , Anopheles/genética , Sequência de Bases , DDT/farmacologia , Regulação da Expressão Gênica , Resistência a Inseticidas , Dados de Sequência Molecular , Família Multigênica , Mutagênese Sítio-Dirigida , Estresse Oxidativo , Regiões Promotoras Genéticas/efeitos dos fármacos , Homologia de Sequência do Ácido Nucleico
9.
Insect Biochem Mol Biol ; 34(7): 653-65, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15242706

RESUMO

Insecticide resistance is an inherited characteristic involving changes in one or more insect gene. The molecular basis of these changes are only now being fully determined, aided by the availability of the Drosophila melanogaster and Anopheles gambiae genome sequences. This paper reviews what is currently known about insecticide resistance conferred by metabolic or target site changes in mosquitoes.


Assuntos
Anopheles/genética , Culicidae/genética , Animais , Drosophila melanogaster/genética , Moscas Domésticas/genética , Canais de Sódio/genética
10.
Mol Cell Biol ; 22(19): 6697-705, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12215527

RESUMO

The general transcription factor TFIIB plays a central role in the selection of the transcription initiation site. The mechanisms involved are not clear, however. In this study, we analyze core promoter features that are responsible for the susceptibility to mutations in TFIIB and cause a shift in the transcription start site. We show that TFIIB can modulate both the 5' and 3' parameters of transcription start site selection in a manner dependent upon the sequence of the initiator. Mutations in TFIIB that cause aberrant transcription start site selection concentrate in a region that plays a pivotal role in modulating TFIIB conformation. Using epitope-specific antibody probes, we show that a TFIIB mutant that causes aberrant transcription start site selection assembles at the promoter in a conformation different from that for wild-type TFIIB. In addition, we uncover a core promoter-dependent effect on TFIIB conformation and provide evidence for novel sequence-specific TFIIB promoter contacts.


Assuntos
Regiões Promotoras Genéticas/fisiologia , Fatores de Transcrição/fisiologia , Sítio de Iniciação de Transcrição/fisiologia , Transcrição Gênica/fisiologia , Região 3'-Flanqueadora/fisiologia , Região 5'-Flanqueadora/fisiologia , Sequência de Bases , Humanos , Substâncias Macromoleculares , Dados de Sequência Molecular , Mutação , Ligação Proteica/fisiologia , Conformação Proteica , Relação Estrutura-Atividade , Especificidade por Substrato , Fator de Transcrição TFIIB , Fatores de Transcrição/química , Fatores de Transcrição/genética
11.
Biochim Biophys Acta ; 1574(1): 51-62, 2002 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-11955613

RESUMO

Resistance to organophosphorus (OP) insecticides in the mosquito Culex quinquefasciatus is primarily due to the amplification and over-expression of non-specific esterases. Co-amplification of two esterase genes, estalpha2(1) and estbeta2(1), is the most common resistance genotype. In both resistant and susceptible mosquitoes the alpha- and beta-esterase genes are oriented in a head-to-head arrangement, the intergenic sequences containing promoter elements for the divergent transcription of both esterases. Transient transfection of luciferase reporter gene constructs into a C. quinquefasciatus cell line was used to study these promoters. A control vector was constructed with the strong Drosophila actin 5c promoter driving expression of beta-galactosidase. The beta-esterase promoters from both insecticide resistant and -susceptible insects were highly active in directing luciferase expression. Transfections with panels of deletions revealed several regions where binding sites for positive and negative regulatory elements are located, and candidate transcription factor sites have been identified. Gel shift assays have identified one DNA-protein interaction that is stronger with the resistant than with the equivalent but slightly altered susceptible sequence. The arthropod initiator site TCAGT 135bp upstream of the ATG in both beta-esterase promoters is essential for transcription initiation, but a putative TATA box is not involved.


Assuntos
Culex/genética , Esterases/genética , Genes de Insetos , Inseticidas , Controle de Mosquitos , Compostos Organofosforados , Regiões Promotoras Genéticas , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Culex/enzimologia , Resistência a Medicamentos , Esterases/biossíntese , Vetores Genéticos , Luciferases/biossíntese , Luciferases/genética , Dados de Sequência Molecular , Transcrição Gênica , Transfecção , beta-Galactosidase/biossíntese , beta-Galactosidase/genética
12.
J Biol Chem ; 277(4): 3047-52, 2002 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-11714725

RESUMO

Human Elongator complex was purified to virtual homogeneity from HeLa cell extracts. The purified factor can exist in two forms: a six-subunit complex, holo-Elongator, which has histone acetyltransferase activity directed against histone H3 and H4, and a three-subunit core form, which does not have histone acetyltransferase activity despite containing the catalytic Elp3 subunit. Elongator is a component of early elongation complexes formed in HeLa nuclear extracts and can interact directly with RNA polymerase II in solution. Several human homologues of the yeast Elongator subunits were identified as subunits of the human Elongator complex, including StIP1 (STAT-interacting protein 1) and IKAP (IKK complex-associated protein). Mutations in IKAP can result in the severe human disorder familial dysautonomia, raising the possibility that this disease might be due to compromised Elongator function and therefore could be a transcription disorder.


Assuntos
Acetiltransferases/química , Acetiltransferases/isolamento & purificação , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Saccharomyces cerevisiae , Acetiltransferases/metabolismo , Sequência de Aminoácidos , Animais , Western Blotting , Proteínas de Transporte/química , Linhagem Celular , Núcleo Celular/metabolismo , Clonagem Molecular , Disautonomia Familiar/genética , Disautonomia Familiar/metabolismo , Células HeLa , Histona Acetiltransferases , Histonas/química , Humanos , Insetos , Dados de Sequência Molecular , Mutação , Ligação Proteica , Estrutura Terciária de Proteína , RNA Polimerase II/metabolismo , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Fatores de Elongação da Transcrição
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