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1.
Nat Commun ; 7: 12359, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27459299

RESUMO

The health of cloned animals generated by somatic-cell nuclear transfer (SCNT) has been of concern since its inception; however, there are no detailed assessments of late-onset, non-communicable diseases. Here we report that SCNT has no obvious detrimental long-term health effects in a cohort of 13 cloned sheep. We perform musculoskeletal assessments, metabolic tests and blood pressure measurements in 13 aged (7-9 years old) cloned sheep, including four derived from the cell line that gave rise to Dolly. We also perform radiological examinations of all main joints, including the knees, the joint most affected by osteoarthritis in Dolly, and compare all health parameters to groups of 5-and 6-year-old sheep, and published reference ranges. Despite their advanced age, these clones are euglycaemic, insulin sensitive and normotensive. Importantly, we observe no clinical signs of degenerative joint disease apart from mild, or in one case moderate, osteoarthritis in some animals. Our study is the first to assess the long-term health outcomes of SCNT in large animals.


Assuntos
Envelhecimento/fisiologia , Clonagem de Organismos , Ovinos/fisiologia , Adiposidade , Angiotensina II/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Composição Corporal , Transferência Embrionária , Teste de Tolerância a Glucose , Frequência Cardíaca/efeitos dos fármacos , Resistência à Insulina , Articulações/diagnóstico por imagem , Articulações/efeitos dos fármacos , Imageamento por Ressonância Magnética , Ovinos/genética , Sístole/efeitos dos fármacos
2.
Science ; 307(5710): 696-8, 2005 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-15692044

RESUMO

Saturn was imaged between 8 and 24.5 micrometers at approximately 3000-kilometer resolution with the Keck I Telescope. Saturn's atmosphere has zonal temperature bands, which are mostly uncorrelated with visible cloud reflectivity, strong 100-millibar zonal temperature oscillations near 32 degrees S, a warm south polar cap, and a compact hot point within 3 degrees of the south pole.

3.
Tsitologiia ; 47(3): 243-8, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16706169

RESUMO

Nuclei of ovarian pseudonurse cells from the mutant strain of Drosophila melanogaster otu 11 are suitable for mapping the attachment of chromosomes to the nuclear envelope (NE). Loci in contact with the NE included region 20CD of the X chromosome, region 41 of chromosome 2, the proximal end of region 81 of chromosome 3, and region 101 of chromosome 4. In situ hybridization revealed that all 4 regions contained sequences homologous to clone lambda20p1.4. DNA of clone lambda20p1.4 was previously found to bind specifically to purified D. melanogaster lamins. These results suggest that specific DNA sequences are involved in attachment of chromosomes to NE in vivo.


Assuntos
Cromossomos/metabolismo , DNA/metabolismo , Drosophila melanogaster/genética , Membrana Nuclear/metabolismo , Ovário/citologia , Animais , Cromatina/genética , Cromatina/metabolismo , Mapeamento Cromossômico , Cromossomos/genética , DNA/genética , Feminino , Cromossomo X/metabolismo
4.
Tsitologiia ; 47(3): 249-54, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16706170

RESUMO

A combined approach based on cytological observations in situ hybridization, and qualitative Southern-blot analyses were used to localize the proximal border of the right arm of polytene chromosome 2 in Drosophila melanogaster otu 11 strain. A genetically functional chromosome 2 is bounded by "deletions" C', C, D, B, A and ms2-10. Using in situ hybridization in conjunction with comparative quantitative Southern-blot hybridization to deletions in centromeric heterochromatin, DNA of specific centromeric clone lambda20p1.4 was localized with respect to "deletions" and on otu 11 polytene chromosomes. Comparison of hybridization sites of lambda20p1.4 on polytene chromosomes, and its amount in mutant lines of D. melanogaster carrying known "deletions" in the centromeric heterochromatin enabled us to localize the proximal border of the right arm of chromosome 2 in D. melanogaster otu 11 strain between the 39/40 region and hybridization site of the k20p1.4 DNA fragment.


Assuntos
Cromossomos/genética , Drosophila melanogaster/genética , Animais , Southern Blotting , Mapeamento Cromossômico
5.
Complement Ther Med ; 12(1): 6-16, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15130567

RESUMO

BACKGROUND: The use of Complementary and Alternative Medicine (CAM) in primary care is growing, but still not widespread. Little is known about how CAM can/should be integrated into mainstream care. OBJECTIVES: To assess primary care health professionals' perceptions of need and of some ways to integrate CAM in primary care. METHOD: Questionnaire survey of primary health care workers in Northwest London. General Practitioners (GPs) were targeted in a postal survey, other members of the primary care team, such as district and practice nurses, were targeted via colleagues. The questionnaire assessed health care professionals' perspective on complementary medicine, referrals, ways to integrate complementary medicine into primary care and interest in research on CAM. RESULTS: Responses were obtained from 149 GPs (40% response rate after one reminder) and 24 nurses and 32 other primary care team members. One hundred and seventy-one (83%) respondents had previously referred (or influenced referral) for CAM treatments, the main reasons cited were: patients request (68%), conventional treatments failed (58%) and evidence (36%) (more than one reason could be given). Acupuncture and homoeopathy were the therapies for which patients were most frequently referred, followed by manual therapies. There was a significant interest in more training/information on CAM (66%). Only 12 respondents (6%) were against any integration of CAM in mainstream primary care. Most respondents felt that CAM therapies should be provided by doctors (66%) or other health professionals trained in CAM (82%). Twenty-six percent of respondents agreed with provision of CAM by non-state-registered practitioners. It was felt that the integration of CAM could lead to cost savings (70%), particularly in conditions involving pain, but also cost increases (55%) particularly in 'poorly defined conditions'. Fifty-six percent of respondents would consider participating in studies investigating CAM. The greatest interest was in acupuncture (41% of those who expressed an interest in research), homoeopathy (30%) and therapeutic massage/aromatherapy (26%). CONCLUSIONS: There is considerable interest in CAM among primary care professionals, and many are already referring or suggesting referral. Such referrals are driven mainly by patient demand and by dissatisfaction with the results of conventional medicine. Most of our respondents were in favour of integrating at least some types of CAM in mainstream primary care. There is an urgent need to further educate/inform primary care health professionals about CAM.


Assuntos
Competência Clínica , Terapias Complementares/normas , Prestação Integrada de Cuidados de Saúde , Atenção Primária à Saúde/normas , Adulto , Idoso , Atitude do Pessoal de Saúde , Terapias Complementares/tendências , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Médicos de Família , Padrões de Prática Médica , Atenção Primária à Saúde/tendências , Inquéritos e Questionários , Reino Unido
6.
Anim Biotechnol ; 13(1): 149-58, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12212938

RESUMO

Ovine interferon tau (oIFN-tau) is an embryonic protein of critical importance in the establishment of pregnancy in the sheep. We have produced recombinant (r) oIFN-tau using a baculovirus expression system and demonstrated the biological activity of the protein produced. Bombyx mori larvae were infected with B. mori nuclear polyhedrosis virus (BmNPV), modified by inserting a cDNA coding for oIFN-tau downstream of the strong polyhedron promoter. Following infection, antiviral activity of the haemolymph rose to a maximum of 3.6 x 10(8) u/mL (equivalent to 3 mg roIFN-tau/mL) by day 5, when haemolymph was collected and stored frozen. Control haemolymph, collected from uninfected insects at an equivalent time, contained no antiviral activity. The roIFN-tau was partially purified by gel filtration column chromatography and the presence of roIFN-tau confirmed by western blotting. The biological activity of the partially purified roIFN-tau was tested in ewes. Treatment with roIFN-tau caused a significant delay in luteolysis confirming biological potency. The results demonstrate that this system can be successfully used to produce large quantities of roIFN-tau.


Assuntos
Bombyx/virologia , Clonagem Molecular/métodos , Dinoprosta/análogos & derivados , Interferon Tipo I/biossíntese , Nucleopoliedrovírus/genética , Proteínas da Gravidez/biossíntese , Ovinos/fisiologia , Animais , Western Blotting/veterinária , Cromatografia em Gel/veterinária , Dinoprosta/sangue , Feminino , Técnicas In Vitro , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Interferon Tipo I/farmacologia , Luteólise/efeitos dos fármacos , Nucleopoliedrovírus/metabolismo , Gravidez , Proteínas da Gravidez/genética , Proteínas da Gravidez/metabolismo , Proteínas da Gravidez/farmacologia , Progesterona/sangue , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia
7.
Domest Anim Endocrinol ; 23(1-2): 13-24, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12142222

RESUMO

In several transformed cell lines, the growth factors IGF-I and epidermal growth factor (EGF) activate second messenger systems that cause the phosphorylation of the estrogen receptor (ER). One kinase catalysing receptor phosphorylation is mitogen activated protein (MAP) kinase, and the result of phosphorylation is an increase in receptor transactivation function. EGF and IGF-I, secreted locally and systemically, are involved in uterine-conceptus interactions in early pregnancy, and therefore it is of interest to determine whether these growth factors affect ER function in the uterus. An estrogen response element, chloramphenicol acetyl transferase reporter gene construct (CATERE) was transfected into bovine endometrial epithelial and stromal cells in vitro, and CAT measured during transient expression. Growth factors were added at various times following transfection, and MAP kinase phosphorylation was monitored by western blotting of p42 and p44. The MEK inhibitor U 0126 was used to determine whether the effect of IGF-I on CATERE expression was mediated through MAP kinase, and the anti-estrogen ICI 182780 was used to identify effects involving the ER. In stromal cells, reporter gene activity was increased in a dose dependent manner by IGF-I or hEGF in the presence or absence of estradiol-17beta. In the absence of estradiol the effect of IGF-I was not inhibited by ICI 182780. The effect of IGF-I occurred within an hour, before any detectable increase in cell proliferation, and the activation of CAT expression in response to IGF-I or EGF was blocked by U 0126. In contrast to their effects in stromal cells, neither IGF-I nor EGF affected CAT expression in bovine endometrial epithelial cells. Measurement of phosphorylated MAP kinases p42/p44 by western blotting showed that EGF but not IGF-I activated MAP kinase phosphorylation in both epithelial and stromal cells. In stromal cells, the fact that U 0126 blocked the CAT responses to IGF-I and EGF indicates the involvement of a MAP kinase. But since IGF-I did not activate p42/p44, a different MAP kinase, not detected by the antibody used here, is implicated. As the response was not blocked by ICI 182780, we conclude this effect is independent of ER activation. Therefore in bovine uterine cells in culture effects on MAP kinases p42/p44 can be dissociated from those on ERE-dependent gene expression, and reporter gene expression may be independent of ER activation.


Assuntos
Bovinos , Receptores de Estrogênio/fisiologia , Animais , Butadienos/farmacologia , Células Cultivadas , Cloranfenicol O-Acetiltransferase/análise , Cloranfenicol O-Acetiltransferase/genética , Endométrio/metabolismo , Inibidores Enzimáticos/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Células Epiteliais/metabolismo , Estradiol/análogos & derivados , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Estrogênios , Feminino , Fulvestranto , Expressão Gênica , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Nitrilas/farmacologia , Elementos de Resposta , Células Estromais/metabolismo , Transfecção
8.
Holist Nurs Pract ; 15(2): 47-58, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12119919

RESUMO

This study investigated whether relaxation training would increase caregivers' self-efficacy for controlling anxiety associated with difficult behaviors by care recipients. Thirty-six individuals caring for relatives with Alzheimer's disease were taught four types of relaxation techniques. Caregivers' self-efficacy increased following the intervention. Length of time spent in the caregiving role and duration of time since care recipients' diagnosis were significantly related to caregiver self-efficacy before the intervention, but became non-significant following the intervention. An insignificant decrease in incidence of reported behavioral problems occurred following the intervention.


Assuntos
Doença de Alzheimer/terapia , Ansiedade/prevenção & controle , Cuidadores/psicologia , Relaxamento/psicologia , Autoeficácia , Adaptação Psicológica , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa em Enfermagem , Ontário , Inquéritos e Questionários , Fatores de Tempo
9.
J Am Acad Child Adolesc Psychiatry ; 39(11): 1356-64, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11068890

RESUMO

OBJECTIVE: This article describes the results of a pilot study that evaluated the effectiveness of the Early Intervention Foster Care (EIFC) program in the period immediately following a child's placement in a new foster home. METHOD: Data were collected from an EIFC group, a regular foster care group, and a community comparison group-each with 10 participants-via questionnaires for children and their caretakers and salivary cortisol sampling. RESULTS: EIFC foster parents adopted and maintained positive parenting strategies, EIFC children's behavioral adjustment improved, and changes occurred in several salivary cortisol measures. Moreover, regular foster care children exhibited decrements in functioning in several areas over the same time period. CONCLUSIONS: Results are discussed with regard to how such research fits into a larger program of prevention research for high-risk preschool children.


Assuntos
Cuidadores/psicologia , Maus-Tratos Infantis , Transtornos do Comportamento Infantil/prevenção & controle , Cuidados no Lar de Adoção/psicologia , Hidrocortisona/metabolismo , Programas Médicos Regionais/organização & administração , Ajustamento Social , Estresse Psicológico/prevenção & controle , Negro ou Afro-Americano/psicologia , Análise de Variância , Biomarcadores/sangue , Cuidadores/educação , Criança , Transtornos do Comportamento Infantil/psicologia , Pré-Escolar , Feminino , Cuidados no Lar de Adoção/organização & administração , Humanos , Masculino , Oregon , Saliva/metabolismo , Estresse Psicológico/sangue , Inquéritos e Questionários , População Branca/psicologia
10.
Rheumatology (Oxford) ; 39(7): 714-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10908688

RESUMO

OBJECTIVE: : To evaluate the efficacy and safety of a homeopathic gel vs an NSAID (piroxicam) gel in the treatment of osteoarthritis of the knee. METHOD: : One hundred and eighty-four out-patients with radiographically confirmed symptomatic osteoarthritis of the knee were entered into a pragmatic, randomized, double-blind controlled trial and treated with 1 g of gel three times daily for 4 weeks. Main outcome measures were pain on walking as a Visual Analogue Score (VAS) and a single-joint Ritchie index. RESULTS: : One hundred and seventy-two of the 184 enrolled patients had endpoints for the main outcome parameters. The pain reduction was 16.5 mm VAS in the homeopathy group (n = 86) and 8.1 mm in the piroxicam group (n = 86); the difference between treatment groups was 8.4 mm (95% confidence interval 0.8-15.9), and after adjustment for pain at baseline it was 6.8 mm (95% confidence interval -0.3 to 13.8). There was no significant difference between treatment groups in the single-joint Ritchie index (P = 0.78). Adverse events occurred in 28 patients (12 homeopathy group, 5 withdrawn; 16 piroxicam group, 9 withdrawn); 18 of the events involved a local reaction (7 homeopathy group, 2 withdrawn; 11 piroxicam group, 5 withdrawn). CONCLUSION: : The homeopathic gel was at least as effective and as well tolerated as the NSAID gel. The presence of a clinically relevant difference between treatment groups cannot be excluded. The homeopathic gel supplemented by simple analgesics if required may provide a useful treatment option for patients with osteoarthritis.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Homeopatia , Osteoartrite do Joelho/tratamento farmacológico , Piroxicam/uso terapêutico , Administração Tópica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/efeitos adversos , Método Duplo-Cego , Feminino , Seguimentos , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/complicações , Dor/tratamento farmacológico , Dor/etiologia , Piroxicam/efeitos adversos , Resultado do Tratamento
11.
J Cell Sci ; 113 ( Pt 9): 1635-47, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10751154

RESUMO

DNA topoisomerase II (topo II) is thought to be a nuclear enzyme; during interphase most was insoluble and could be recovered in the pellet after centrifugation of cell homogenates at 10,000 g (P-10). Upon entry into mitosis, the majority of topo II did not associate with condensed chromosomes but was apparently solubilized and redistributed throughout the cell. Although two non-chromosomal subfractions of mitotic topo II were defined by centrifugation at 130,000 g, the vast majority (>90%) was recovered in the pellet (P-130). In vivo nucleic acid interactions with topo II were monitored by a recently developed approach of UV-photo-crosslinking, immunoprecipitation and (32)P-labeling. P-10 (interphase) topo II was largely associated with DNA. P-130 (mitotic non-chromosomal) topo II was primarily associated with RNA. These nucleic acid interactions with both interphase and mitotic topo II occurred through the catalytically inert and as yet, poorly understood C-terminal domain of the protein. P-10 topo II was highly active enzymatically. Activity, measured by the ability of topo II to decatenate kDNA minicircles, was reduced by treatment with phosphatase. In contrast, P-130 topo II was relatively inactive but activity could be increased by phosphatase treatment. In vivo, P-130 topo II was more heavily phosphorylated than P-10 topo II; in both, only the C-terminal domain of topo II was detectably modified. Our observations suggest that cell cycle-dependent changes in the distribution, nucleic acid interactions and enzymatic activity of topo II are regulated, at least in part, by phosphorylation/dephosphorylation.


Assuntos
DNA Topoisomerases Tipo II/metabolismo , DNA/metabolismo , Interfase , Mitose , RNA/metabolismo , Animais , DNA Topoisomerases Tipo II/química , Drosophila melanogaster , Mitose/efeitos dos fármacos , Fosforilação , Vimblastina/farmacologia
12.
J Interferon Cytokine Res ; 20(2): 225-33, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10714559

RESUMO

Exposure to type I interferons (IFN) increased estrogen receptor (ER) ligand binding and induced protein kinase C (PKC) translocation within 30 min but had no effect on net incorporation of [32P] into ER in Madin Darby bovine kidney (MDBK) cells. Ligand binding was also increased within 30 min by phorbol ester and the protein phosphatase inhibitor okadaic acid. Mitogen-activated protein (MAP) kinase phosphorylation was initially inhibited between 2 and 30 min and subsequently activated between 30 and 60 min after treatment with IFN. The activatory response was blocked by the PKC inhibitor Ro 31-8220. Following transient transfection with an ERE-CAT reporter construct, IFN increased CAT expression after 6 h but decreased ER ligand binding, transcriptional activity and phosphorylation after 48 h, probably as a result of decreased ER concentrations. The results rule out rapid activation of ER ligand binding through phosphorylation at Ser118 by MAP kinase because (1) the increase in ligand binding preceded activation of MAP kinase, and (2) IFN had no short-term effect on [32P]incorporation or ER transcriptional activity. The rapid effect of IFN on ER ligand binding is postulated to reflect phosphorylation of the receptor at Tyr537 by p56lck, a member of the Src family of PKC-activated tyrosine kinases.


Assuntos
Interferon Tipo I/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/metabolismo , Animais , Bovinos , Linhagem Celular , Cloranfenicol O-Acetiltransferase/genética , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Estradiol/metabolismo , Expressão Gênica/efeitos dos fármacos , Genes Reporter , Indóis/farmacologia , Cinética , Proteína Quinase 3 Ativada por Mitógeno , Fosforilação , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Receptores de Estrogênio/genética , Proteínas Recombinantes
14.
Methods ; 18(3): 401-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10455000

RESUMO

Proliferating cell nuclear antigen (PCNA), a protein intimately involved in both replication and repair, has been identified in eukaryotes at all levels of evolution. Is primary sequence, Drosophila melanogaster PCNA is 73% identical to mammalian PCNA. Moreover, it is able to substitute for mammalian PCNA in at least one intricate cell-free replication assay. Mutations in the gene for Drosophila PCNA, including some that are temperature sensitive, have been reported. Procedures are described for the biochemical purification of wild-type PCNA from a population of 6- to 18-h-old Drosophila embryos. Procedures were also developed for purification of unmodified wild-type Drosophila PCNA after induction of expression in Escherichia coli. An NH(2)-terminally His-tagged but otherwise wild-type Drosophila PCNA, as well as mutant His-tagged PCNA, were also engineered and purified to apparent homogeneity. Finally, an in situ polyacrylamide gel technique allows DNA polymerase assays to be performed on portions of single adults as well as single Drosophila embryos. This assay should tremendously facilitate systematic genetic studies of metazoan replication and repair.


Assuntos
Reparo do DNA/genética , Replicação do DNA/genética , Drosophila/genética , Antígeno Nuclear de Célula em Proliferação/análise , Animais , Sequência de Bases , DNA Polimerase Dirigida por DNA/análise , Drosophila/embriologia , Escherichia coli , Feminino , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Plasmídeos , Antígeno Nuclear de Célula em Proliferação/isolamento & purificação , Proteínas Recombinantes/análise
15.
Am J Orthopsychiatry ; 69(3): 294-304, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10439844

RESUMO

This study examines how relations between risk and protective factors and psychopathology vary by ethnic group, gender, and informant. Data were collected from Caucasian and American Indian adolescents, and their teachers. Results indicate a need for interventions that reduce risk, increase protective factors, and bring about greater convergence in the perceptions of teachers and youth.


Assuntos
Comportamento do Adolescente/psicologia , Indígenas Norte-Americanos/psicologia , Transtornos Mentais/prevenção & controle , População Rural , População Branca/psicologia , Adolescente , Criança , Etnicidade/psicologia , Feminino , Humanos , Masculino , Fatores de Risco , Fatores Sexuais , Ensino , Estados Unidos
16.
J Biol Chem ; 274(28): 19862-7, 1999 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-10391931

RESUMO

The relative positions of components of the DNA-dependent DNA polymerase delta (pol delta).proliferating cell nuclear antigen (PCNA).DNA complex were studied. We have shown that pol delta incorporates nucleotides close to a template biotin-streptavidin complex located 5' (downstream) to the replicating complex in the presence or absence of PCNA. PCNA-dependent synthesis catalyzed by pol delta was nearly totally (95%) inhibited by a biotin. streptavidin complex located at the 3'-end of a template with a 15-mer primer (upstream of the replicating complex), but was only partially inhibited with a 19-mer primer. With either primer, PCNA-independent synthesis was not affected by the biotin. streptavidin complex. Quantification of results with primers of varying length suggested that pol delta interacts with between 8 and 10 nucleotides of duplex DNA immediately proximal to the 3'-OH primer terminus. Using UV photocross-linking, we determined that the 125-kDa subunit of pol delta, but not the 50-kDa subunit, interacted with a photosensitive residue of a substrate oligonucleotide. Interaction apparently takes place through the C terminus of p125. Based on these results, we conclude that PCNA is located "behind" pol delta in the polymerization complex during DNA synthesis and that only the large subunit of pol delta (two-subunit form) interacts directly with DNA. A detailed model of the enzymatically active complex is proposed.


Assuntos
DNA Polimerase III/química , Antígeno Nuclear de Célula em Proliferação/química , Animais , Sequência de Bases , Biotina/farmacologia , Biotinilação , Bovinos , DNA/biossíntese , Primers do DNA , DNA de Cadeia Simples/química , Modelos Moleculares , Dados de Sequência Molecular , Complexos Multienzimáticos/química , Oligonucleotídeos/química , Fotólise , Estreptavidina/farmacologia , Moldes Genéticos , Timo/enzimologia , Raios Ultravioleta
17.
Biochemistry ; 38(14): 4620-32, 1999 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-10194384

RESUMO

Phosphorylation can have profound effects on the properties of nuclear lamins. For instance, phosphorylation of specific sites on mammalian lamins drastically alters their propensity to polymerize. Relatively little is known about the effects of phosphorylation during interphase and about phosphorylation of invertebrate nuclear lamins. Here, using electrospray ionization tandem mass spectrometry, we determined the phosphorylation sites of both interphase and M-phase isoforms of nuclear lamin Dm from Drosophila melanogaster. Interphase lamins are phosphorylated at three sites: two of these sites (Ser25 and a site located between residues 430 and 438) flank the alpha-helical rod domain, whereas the third site (Ser595) is located close to the C-terminus. The M-phase lamin isoform is phosphorylated predominantly at Ser45, a residue contained within a sequence matching the consensus site for phosphorylation by cdc2 kinase. Our study confirms the important role in vivo for cdc2 kinase in M-phase disassembly of nuclear lamins and provides the basis for understanding Drosophila lamin phosphorylation during interphase.


Assuntos
Drosophila melanogaster/química , Interfase , Meiose , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Sequência de Aminoácidos , Animais , Galinhas , Humanos , Laminas , Espectrometria de Massas/métodos , Camundongos , Dados de Sequência Molecular , Mapeamento de Peptídeos/métodos , Fosfopeptídeos/análise , Fosforilação
18.
Anal Biochem ; 268(2): 193-200, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10075808

RESUMO

Whatman 3MM paper was chemically modified to generate nickel-charged iminodiacetic acid paper (Ni2+-IDA paper). Bacteria were transformed with Escherichia coli expression plasmids coding for either unmodified proliferating cell nuclear antigen (PCNA) or PCNA containing a genetically engineered polyhistidine tract (his-tag) located at its NH2 terminus. They were then grown, induced, and lysed, and macromolecules were transferred to Ni2+-IDA paper. After exhaustive washing, his-tagged PCNA but not unmodified PCNA remained bound to the paper. Moreover, bound his-tagged PCNA was biochemically active in an in situ DNA synthesis assay with exogenous template-primer and purified calf thymus DNA polymerase delta (pol delta). Ni2+-IDA paper was used to identify a PCNA- point mutant that, relative to wild-type PCNA, promotes increased DNA synthesis by pol delta beyond a model abasic template site. In addition, metal-charged IDA paper promises to be generally useful for functional screening of cells expressing cloned proteins.


Assuntos
Mutação Puntual , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Bovinos , DNA/biossíntese , DNA Polimerase III/metabolismo , Primers do DNA/genética , Drosophila/genética , Escherichia coli/genética , Histidina/química , Técnicas In Vitro , Papel , Antígeno Nuclear de Célula em Proliferação/análise , Proteínas Recombinantes/análise , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Timo/enzimologia , Transformação Genética
19.
Artigo em Inglês | MEDLINE | ID: mdl-9842063

RESUMO

Previous research on the mental health status of American Indian youth has documented rates of pathology that are higher than the rates for Caucasian youth. However, much of this previous research has compared rural American Indians to urban Caucasians. The present study is a comparison of American Indian and Caucasian youth living on or near a rural reservation. Results suggest that although American Indian youth have higher levels than Caucasian youth of certain problem behaviors, group differences are much less general and pronounced than previous research has documented. Analyses also revealed teachers' perceptions of youth were in some cases quite different than parents' perceptions of youth and youth's perceptions of themselves.


Assuntos
Indígenas Norte-Americanos/psicologia , Transtornos Mentais/diagnóstico , Transtornos Mentais/psicologia , Pais , População Rural , Ensino , População Branca/psicologia , Adolescente , Comportamento do Adolescente/psicologia , Feminino , Humanos , Masculino , Psicologia do Adolescente , Autoimagem
20.
Mol Cell Biol ; 18(7): 4315-23, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9632815

RESUMO

The nuclear envelope plays many roles, including organizing nuclear structure and regulating nuclear events. Molecular associations of nuclear envelope proteins may contribute to the implementation of these functions. Lamin, otefin, and YA are the three Drosophila nuclear envelope proteins known in early embryos. We used the yeast two-hybrid system to explore the interactions between pairs of these proteins. The ubiquitous major lamina protein, lamin Dm, interacts with both otefin, a peripheral protein of the inner nuclear membrane, and YA, an essential, developmentally regulated protein of the nuclear lamina. In agreement with this interaction, lamin and otefin can be coimmunoprecipitated from the vesicle fraction of Drosophila embryos and colocalize in nuclear envelopes of Drosophila larval salivary gland nuclei. The two-hybrid system was further used to map the domains of interaction among lamin, otefin, and YA. Lamin's rod domain interacts with the complete otefin protein, with otefin's hydrophilic NH2-terminal domain, and with two different fragments derived from this domain. Analogous probing of the interaction between lamin and YA showed that the lamin rod and tail plus part of its head domain are needed for interaction with full-length YA in the two-hybrid system. YA's COOH-terminal region is necessary and sufficient for interaction with lamin. Our results suggest that interactions with lamin might mediate or stabilize the localization of otefin and YA in the nuclear lamina. They also suggest that the need for both otefin and lamin in mediating association of vesicles with chromatin might reflect the function of a protein complex that includes these two proteins.


Assuntos
Proteínas Cromossômicas não Histona , Proteínas de Ligação a DNA , Proteínas de Drosophila , Drosophila melanogaster/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Nucleares/metabolismo , Animais , Sítios de Ligação , Extratos Celulares , Núcleo Celular/metabolismo , Técnica Indireta de Fluorescência para Anticorpo , Laminas , Hibridização de Ácido Nucleico , Oócitos/metabolismo , Testes de Precipitina , Glândulas Salivares/metabolismo , Cloreto de Sódio
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