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1.
Ther Apher Dial ; 26(1): 45-54, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34115437

RESUMEN

Vadadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor approved in Japan for the treatment of anemia in patients with chronic kidney disease (CKD). This phase 3, open-label, single-arm study evaluated the efficacy and safety of vadadustat in 24 Japanese patients with CKD-associated anemia on hemodialysis who were not receiving erythropoiesis-stimulating agents (ESAs). Patients received vadadustat for 24 weeks; the starting dose was 300 mg/day and doses were adjusted to achieve the target hemoglobin (Hb) range of 10.0-12.0 g/dL. The least squares mean of average Hb at Weeks 20 and 24 (95% confidence interval) was 10.75 g/dL (10.35, 11.14). The most common adverse event was shunt stenosis (25.0%). Adverse drug reactions (diarrhea and vomiting) occurred in two patients (8.3%) and the severity was mild. Vadadustat increased and maintained Hb levels within the target range and was generally well-tolerated in Japanese patients with anemia on hemodialysis not receiving ESAs.


Asunto(s)
Anemia/tratamiento farmacológico , Anemia/etiología , Glicina/análogos & derivados , Ácidos Picolínicos/uso terapéutico , Diálisis Renal/efectos adversos , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/terapia , Femenino , Glicina/uso terapéutico , Hematínicos , Humanos , Japón , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
2.
J Diabetes Investig ; 13(1): 54-64, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34212533

RESUMEN

AIMS/INTRODUCTION: The sodium-glucose cotransporter 2 inhibitor, canagliflozin, reduced kidney failure and cardiovascular events in the Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE) trial. We carried out a post-hoc analysis to evaluate the efficacy and safety of canagliflozin in a subgroup of participants in East and South-East Asian (EA) countries who are at high risk of renal complications. MATERIALS AND METHODS: Participants with an estimated glomerular filtration rate of 30 to <90 mL/min/1.73 m2 and urinary albumin-to-creatinine ratio of >300-5,000 mg/g were randomized to 100 mg of canagliflozin or a placebo. The effects of canagliflozin treatment on pre-specified efficacy and safety outcomes were examined using Cox proportional hazards regression between participants from EA countries (China, Japan, Malaysia, the Philippines, South Korea and Taiwan) and the remaining participants. RESULTS: Of 4,401 participants, 604 (13.7%) were from EA countries; 301 and 303 were assigned to the canagliflozin and placebo groups, respectively. Canagliflozin lowered the risk of primary outcome (composite of end-stage kidney disease, doubling of serum creatinine level, or renal or cardiovascular death) in EA participants (hazard ratio 0.54, 95% confidence interval 0.35-0.84). The effects of canagliflozin on renal and cardiovascular outcomes in EA participants were generally similar to those of the remaining participants. Safety outcomes were similar between the EA and non-EA participants. CONCLUSIONS: In the CREDENCE trial, the risk of renal and cardiovascular events was safely reduced in participants from EA countries at high risk of renal events.


Asunto(s)
Canagliflozina/uso terapéutico , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Nefropatías Diabéticas/tratamiento farmacológico , Fallo Renal Crónico/prevención & control , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Adulto , Albuminuria/sangre , Albuminuria/orina , Asia Sudoriental , Enfermedades Cardiovasculares/etiología , Creatinina/sangre , Creatinina/orina , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/metabolismo , Método Doble Ciego , Asia Oriental , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Humanos , Riñón/efectos de los fármacos , Fallo Renal Crónico/etiología , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Resultado del Tratamiento
3.
Vaccine ; 39(39): 5513-5523, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34454786

RESUMEN

BACKGROUND: This study is the first clinical trial for a parenteral non-replicating rotavirus vaccine developed using virus-like particle (VLP) technology. METHODS: This open-labeled, randomized, placebo-controlled trial was conducted in two parts: Part A (a first-in-human study in Australian adults) and Part B (ascending dose and descending age in South African adults, toddlers and infants). In Part A, two cohorts of 10 adults were assigned to receive a single intramuscular injection of 1 of 2 escalating dose levels of the rotavirus VLP (Ro-VLP) vaccine (7 µg or 21 µg) or placebo. In Part B, one cohort of 10 adults was assigned to receive a single injection of the Ro-VLP vaccine (21 µg) or placebo, two cohorts of 10 toddlers were assigned to receive 2 injections of 1 of 2 escalating dose levels of the Ro-VLP vaccine (7 µg or 21 µg) or placebo 28 days apart, and three cohorts of 20 infants were assigned to receive 3 injections of 1 of 3 escalating dose levels of the Ro-VLP vaccine (2.5 µg, 7 µg or 21 µg) or placebo or 2 doses of oral Rotarix 28 days apart. Safety, reactogenicity and immunogenicity were assessed. RESULTS: There were no safety or tolerability concerns after administration of the Ro-VLP vaccine. The Ro-VLP vaccine induced an anti-G1P[8] IgG response in infants 4 weeks after the second and third doses. Neutralizing antibody responses against homologous G1P[8] rotavirus were higher in all Ro-VLP infant groups than in the placebo group 4 weeks after the third dose. No heterotypic immunity was elicited by the Ro-VLP vaccine. CONCLUSIONS: The Ro-VLP vaccine was well tolerated and induced a homotypic immune response in infants, suggesting that this technology platform is a favorable approach for a parenteral non-replicating rotavirus vaccine. CLINICAL TRIAL REGISTRATION: NCT03507738.


Asunto(s)
Vacunas contra Rotavirus , Rotavirus , Vacunas de Partículas Similares a Virus , Adulto , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Australia , Preescolar , Método Doble Ciego , Humanos , Inmunogenicidad Vacunal , Lactante , Vacunas contra Rotavirus/efectos adversos
4.
J Am Soc Nephrol ; 32(7): 1779-1790, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33883252

RESUMEN

BACKGROUND: Standard care for treating anemia in patients with CKD includes use of erythropoiesis-stimulating agents, which sometimes involves increased risks of cardiovascular morbidity and mortality. Previous studies in patients with anemia and nondialysis-dependent CKD (NDD-CKD) found significantly elevated hemoglobin levels with use of vadadustat, an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, compared with placebo. METHODS: In this phase 3, open-label, active-controlled noninferiority trial, we randomized 304 Japanese adults with anemia in NDD-CKD (including erythropoiesis-stimulating agent users and nonusers) to oral vadadustat or subcutaneous darbepoetin alfa for 52 weeks. The primary efficacy end point was average hemoglobin at weeks 20 and 24. Safety data included adverse events (AEs) and serious AEs. RESULTS: A total of 151 participants received vadadustat and 153 received darbepoetin alfa. Least squares mean of the average hemoglobin at weeks 20 and 24 was 11.66 (95% confidence interval [95% CI], 11.49 to 11.84) g/dl for vadadustat and 11.93 (95% CI, 11.76 to 12.10) g/dl for darbepoetin alfa. The 95% CIs for both treatments were within the target hemoglobin range (11.0-13.0 g/dl), and the lower 95% confidence limit for the difference between groups (-0.50 g/dl) was above the predefined noninferiority margin (-0.75 g/dl), demonstrating noninferiority of vadadustat to darbepoetin alfa. Similar proportions of patients in each group reported AEs and serious AEs. The most frequent AEs with vadadustat were nasopharyngitis, diarrhea, and constipation. CONCLUSIONS: In Japanese patients with NDD-CKD, vadadustat was noninferior to darbepoetin alfa, was effective up to week 52 in terms of average hemoglobin, and was generally well tolerated. These results suggest that vadadustat may be a potential treatment for anemia in this patient population.

5.
Nephrol Dial Transplant ; 36(9): 1731-1741, 2021 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-33650630

RESUMEN

BACKGROUND: Vadadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor that stimulates erythropoiesis. METHODS: The efficacy and safety of vadadustat, compared with darbepoetin alfa, was determined in a Phase 3 double-blind study in Japanese anemic patients on hemodialysis. Patients receiving erythropoiesis-stimulating agents (ESAs) were randomized and switched to either vadadustat or darbepoetin alfa for 52 weeks. Doses were adjusted to maintain a hemoglobin (Hb) level of 10.0-12.0 g/dL. The primary endpoint was average Hb level at Weeks 20 and 24. RESULTS: Of the 323 randomized patients, 120 and 135 completed the 52-week treatment period in the vadadustat and darbepoetin alfa groups, respectively. The average Hb levels at Weeks 20 and 24 [least square mean (LSM) and 95% confidence interval (CI)] were 10.61 (10.45-10.76) and 10.65 (10.50-10.80) g/dL in the vadadustat and darbepoetin alfa groups, respectively, demonstrating vadadustat's noninferiority to darbepoetin alfa (difference: -0.05 g/dL; 95% CI -0.26 to 0.17). In both groups, the mean Hb levels were maintained within the target range for 52 weeks. Furthermore, irrespective of patient backgrounds, the LSMs of Hb at Week 52 were within the target range. The most common adverse events were nasopharyngitis, diarrhea and shunt stenosis, which occurred at similar frequencies in both groups. No new safety concerns were identified. CONCLUSIONS: Vadadustat was as well-tolerated and effective as darbepoetin alfa in maintaining Hb levels within the target range. The findings suggest that vadadustat can be an alternative to ESA in the management of anemia in Japanese hemodialysis patients receiving ESA (ClinicalTrials.gov, NCT03439137).


Asunto(s)
Anemia , Eritropoyetina , Hematínicos , Anemia/tratamiento farmacológico , Anemia/etiología , Darbepoetina alfa/uso terapéutico , Método Doble Ciego , Glicina/análogos & derivados , Hematínicos/efectos adversos , Hemoglobinas/análisis , Humanos , Japón , Ácidos Picolínicos , Diálisis Renal
6.
Ther Apher Dial ; 25(5): 642-653, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33283981

RESUMEN

Vadadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor for the treatment of anemia in patients with chronic kidney disease (CKD). This phase 3, open-label, 24-week single-arm study evaluated the efficacy and safety of vadadustat in 42 Japanese CKD patients with anemia undergoing peritoneal dialysis. Patients received oral vadadustat for 24 weeks, initiated at 300 mg/day and doses were adjusted to achieve the target hemoglobin (Hb) range of 11.0-13.0 g/dL. Least squares mean of average Hb at weeks 20 and 24 was 11.35 g/dL, which was within the target range. The most frequent adverse events were catheter site infections (23.8%), which were not related to vadadustat treatment. Vadadustat was generally well tolerated and effective in controlling Hb levels within the target range, indicating the usefulness of vadadustat for treating anemia in Japanese CKD patients undergoing peritoneal dialysis.


Asunto(s)
Anemia/tratamiento farmacológico , Anemia/etiología , Glicina/análogos & derivados , Diálisis Peritoneal/efectos adversos , Ácidos Picolínicos/uso terapéutico , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/terapia , Femenino , Glicina/uso terapéutico , Humanos , Japón , Masculino , Persona de Mediana Edad , Diálisis Peritoneal/métodos , Resultado del Tratamiento
7.
Diabetes Obes Metab ; 20(7): 1770-1775, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29473709

RESUMEN

Sodium-glucose co-transporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1RAs) are antihyperglycaemic agents with weight-lowering effects. The efficacy and safety of the SGLT2 inhibitor canagliflozin as add-on therapy in Japanese patients with type 2 diabetes mellitus (T2DM) and inadequate glycaemic control with a GLP-1RA (≥12 weeks) were evaluated in this phase IV study. Patients received canagliflozin 100 mg once daily for 52 weeks. Efficacy endpoints included change in glycated haemoglobin (HbA1c), fasting plasma glucose (FPG), body weight, systolic blood pressure (SBP) and HDL cholesterol from baseline to week 52. Safety endpoints included adverse events (AEs), hypoglycaemia and laboratory tests. Of the 71 patients treated with canagliflozin, 63 completed the study. At 52 weeks, HbA1c was significantly reduced from baseline (-0.70%; paired t test, P < .001). Significant changes were also observed in FPG (-34.7 mg/dL), body weight (-4.46%), SBP (-7.90 mm Hg), and HDL cholesterol (7.60%; all P < .001). The incidence of AEs, adverse drug reactions and hypoglycaemia was 71.8%, 32.4% and 9.9%, respectively. All hypoglycaemic events were mild. These findings suggest that the long-term combination of canagliflozin with a GLP-1RA is effective and well tolerated in Japanese patients with T2DM.


Asunto(s)
Canagliflozina/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Incretinas/uso terapéutico , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Anciano , Glucemia/metabolismo , Presión Sanguínea , Peso Corporal , HDL-Colesterol/metabolismo , Quimioterapia Combinada , Femenino , Receptor del Péptido 1 Similar al Glucagón/agonistas , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemia/inducido químicamente , Japón , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
8.
Diabetes Obes Metab ; 20(4): 812-820, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29110384

RESUMEN

AIM: The aim of this study was to assess the long-term efficacy and safety of canagliflozin as add-on therapy in Japanese patients with type 2 diabetes mellitus who had inadequate glycaemic control with insulin. MATERIALS AND METHODS: The study comprised a 16-week, double-blind period in which patients were randomized to either placebo (P; N = 70) or canagliflozin (100 mg, CAN; N = 76), followed by a 36-week open-label period in which all patients received canagliflozin. The efficacy endpoints included the change in HbA1c from baseline to end of treatment. The safety endpoints were adverse events, hypoglycaemic events, and laboratory test values. RESULTS: The changes from baseline (mean ± standard deviation, last observation carried forward) in the P/CAN and CAN/CAN groups, respectively, were -1.09% ± 0.85% and -0.88% ± 0.86% for HbA1c, -1.40% ± 2.54% and -2.14% ± 2.75% for body weight, and 7.84% ± 14.37% and 8.91% ± 10.80% for HOMA2-%B (all, P < .001). Adverse events occurred in 85.1% of the P/CAN group and 92.0% of the CAN/CAN group. Hypoglycaemic events occurred in 43.3% and 54.7%, respectively. All hypoglycaemic events were mild in severity and insulin dose reduction decreased the incidence rate of hypoglycaemic events. Post-hoc ordinal logistic modelling/logistic modelling showed that lower serum C-peptide at Week 0 was a risk factor for hypoglycaemia in both the P and CAN groups in the double-blind period as well as in the canagliflozin all-treatment period. CONCLUSIONS: This study demonstrates the long-term efficacy and safety of canagliflozin combined with insulin in Japanese patients.


Asunto(s)
Canagliflozina/administración & dosificación , Canagliflozina/efectos adversos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Insulina/administración & dosificación , Insulina/efectos adversos , Adulto , Pueblo Asiatico , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Método Doble Ciego , Quimioterapia Combinada , Femenino , Hemoglobina Glucada/efectos de los fármacos , Hemoglobina Glucada/metabolismo , Humanos , Japón , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resultado del Tratamiento
9.
Cardiovasc Diabetol ; 15: 89, 2016 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-27316668

RESUMEN

BACKGROUND: Combination therapy with canagliflozin and insulin was investigated in a prescribed substudy of the canagliflozin Cardiovascular Assessment Study (CANVAS); however, it was not evaluated in Japanese patients with type 2 diabetes mellitus (T2DM). Since the usage profile of insulin therapy and pathologic features of Japanese patients differ from those of Caucasian patients, we determined the clinical benefit of such a combination therapy in Japanese patients. METHODS: Patients who had inadequate glycemic control despite insulin, diet and exercise therapies were randomized into placebo (n = 70) and canagliflozin 100 mg (n = 76) groups that were administered once daily in addition to their prior insulin therapy in this double-blind, placebo-controlled study. The primary endpoint was the change in glycated hemoglobin (HbA1c) levels from the baseline to week 16. RESULTS: There was a statistically significant decrease in HbA1c levels from the baseline in the canagliflozin group (-0.97 ± 0.08 %) compared with the placebo group (0.13 ± 0.08 %) at week 16 [last observation carried forward (LOCF)]. The decrease in HbA1c levels in the canagliflozin group was independent of the insulin regimen (premixed, long-acting and long-acting plus rapid- or short-acting). Compared with the placebo group, canagliflozin significantly decreased fasting plasma glucose levels (-34.1 ± 4.8 vs -1.4 ± 5.0 mg/dL) and body weights (-2.13 ± 0.25 vs 0.24 ± 0.26 %), and significantly increased HDL cholesterol (3.3 ± 1.0 vs -0.5 ± 1.0 mg/dL) and HOMA2- %B (10.15 ± 1.37 vs 0.88 ± 1.42 %). The overall incidence of adverse events was similar between the two groups. The incidence and incidence per subject-year exposure of hypoglycemia (hypoglycemic symptoms and/or decreased blood glucose) were slightly higher in the canagliflozin group (40.0 % and 7.97) than in the placebo group (29.6 % and 4.51). However, hypoglycemic events in both groups were mild in severity and dose-reduction of insulin by <10 % from the baseline following hypoglycemic events decreased the incidence per subject-year exposure in the canagliflozin group. The incidence of hypoglycemia between the groups did not differ according to the insulin regimen. CONCLUSION: Canagliflozin in combination with insulin was effective in improving glycemic control and reducing body weight and well tolerated by Japanese patients with T2DM. Trial Registration ClinicalTrials.gov identifier: NCT02220920.


Asunto(s)
Glucemia/efectos de los fármacos , Canagliflozina/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Insulina/sangre , Adulto , Anciano , Pueblo Asiatico , Peso Corporal/efectos de los fármacos , Canagliflozina/efectos adversos , Diabetes Mellitus Tipo 2/sangre , Método Doble Ciego , Femenino , Humanos , Hipoglucemia/inducido químicamente , Hipoglucemiantes/efectos adversos , Masculino , Persona de Mediana Edad , Pérdida de Peso/efectos de los fármacos
10.
Mol Genet Genomics ; 286(3-4): 215-24, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21842267

RESUMEN

Maintenance of genome stability relies on the accurate repair of DNA double-strand breaks (DSBs) that arise during DNA replication or introduced by DNA-damaging agents. Failure to repair such breaks can lead to the introduction of mutations and chromosomal translocations. Several pathways, homologous recombination, single-strand annealing and nonhomologous end-joining, are known to repair DSBs. So far in the silkworm Bombyx mori, these repair pathways have been analyzed using extrachromosomal plasmids in vitro or in cultured cells. To elucidate the precise nature of the chromosomal DSB repair pathways in cultured silkworm cells, we developed a luciferase-based assay system for measuring the frequency of chromosomal homologous recombination and SSA. An I-SceI-induced DSB, within a nonfunctional luciferase gene, could be efficiently repaired by HR. Additionally, the continuous expression of the I-SceI endonuclease in the HR reporter cell allowed us to investigate the interrelationship between HR, SSA and NHEJ. In this study, we demonstrated that chromosome DSBs were mainly repaired by NHEJ and HR, whereas SSA was unlikely to be a dominant repair pathway in cultured silkworm cell. These results indicate that the assay system presented here will be useful to analyze the mechanisms of DSB repair in insect cells.


Asunto(s)
Bombyx/genética , Roturas del ADN de Doble Cadena , Reparación del ADN , Conversión Génica , Animales , Secuencia de Bases , Bombyx/metabolismo , Línea Celular , Cromosomas de Insectos/genética , Cartilla de ADN/genética , Luciferasas/genética , Modelos Genéticos , Reacción en Cadena de la Polimerasa , Recombinación Genética
11.
Appl Microbiol Biotechnol ; 87(6): 2147-56, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20496148

RESUMEN

Baculovirus expression systems (BES) are widely used for recombinant protein production in lepidopteran cells or larvae. However, even in BES, the insolubility of recombinant proteins sometimes makes their expression difficult. In this study, to improve the solubility and yield of foreign proteins, we constructed transgenic silkworms using silkworm heat-shock proteins, Hsp70 and Hsp40, or Hsc70 and Hsp90 co-chaperone Hop. In these transgenic silkworms, the expression levels of the transgenes were under the control of a UAS.hsp mini-promoter driven by a Gal4NFkBp65 activator. When the transgenic silkworm with HSP70 and 40 (TGS-HSP70/40) was infected with BmNPV carrying mC3d and Gal4NFkBp65 under the control of baculovirus polyhedrin or p10 promoters, respectively, the soluble fraction of the His- or His.GST-tagged mC3d increased significantly. Similarly, the transgenic silkworm with HSC70 and HOP (TGS-HOP7) was effective for the expression of a steroid hormone receptor, USP2. In conclusion, the His-tagged baculovirus expression system featuring the chaperone effect TGS-HSP70/40 and TGS-HOP7 silkworms is effective for increasing the yields of soluble and functional foreign gene products.


Asunto(s)
Animales Modificados Genéticamente/genética , Bombyx/genética , Citoplasma/metabolismo , Expresión Génica , Proteínas de Choque Térmico/genética , Proteínas de Insectos/genética , Proteínas Recombinantes/metabolismo , Animales , Animales Modificados Genéticamente/metabolismo , Animales Modificados Genéticamente/virología , Baculoviridae/genética , Baculoviridae/fisiología , Bombyx/metabolismo , Bombyx/virología , Complemento C3d/química , Complemento C3d/genética , Complemento C3d/metabolismo , Citoplasma/genética , Vectores Genéticos/genética , Vectores Genéticos/fisiología , Proteínas de Choque Térmico/metabolismo , Proteínas de Insectos/química , Proteínas de Insectos/metabolismo , Ratones , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Solubilidad
12.
Cell Mol Biol Lett ; 15(1): 118-33, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19943120

RESUMEN

The telomere structures in Bombyx mori are thought to be maintained mainly by the transposition of the specialized telomeric retroelements SART and TRAS. The silkworm genome has telomeric TTAGG repeats and telomerase, but this telomerase displays little or no activity. Here, we report that the transcription of the telomeric retroelements SART1 and TRAS1 is suppressed by the silkworm Piwi subfamily proteins BmAgo3 and Siwi. The silkworm Piwi subfamily was found to be expressed predominantly in the gonads and early embryo, as in other model organisms, but in BmN4 cultured cells, these proteins formed granules that were separate from the nuage, which is a different behaviour pattern. The expression of TRAS1 was increased in BmN4 cells when BmAgo3 or Siwi were silenced by RNAi. Our results suggest that B. mori Piwi proteins are involved in regulating the transposition of telomeric retroelements, and that the functional piRNA pathway is conserved in BmN4 cultured cells.


Asunto(s)
Bombyx/genética , Complejo Silenciador Inducido por ARN/metabolismo , Retroelementos , Telómero/química , Animales , Bombyx/metabolismo , Células Cultivadas , Interferencia de ARN , Complejo Silenciador Inducido por ARN/genética , Secuencias Repetidas Terminales
13.
Anal Biochem ; 392(2): 180-2, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19481053

RESUMEN

Many biological processes are usually coupled to the formation of protein complexes. The yeast two-hybrid system is a powerful tool for analyzing protein-protein interactions. Different patterns of protein modifications, such as glycosylation, phosphorylation, and acetylation, may affect the ability of proteins to interact. In this study, we developed the two-hybrid system that can be used in insect cells. To validate the insect two-hybrid (I2H) system, we analyzed and confirmed the known oligomer or dimer formation of silkworm Rad51 or RPA2-RPA3, respectively. The results established the feasibility of the I2H system for efficient analysis of protein interaction under conditions that closely reflect the normal physiological environment.


Asunto(s)
Bombyx/metabolismo , Proteínas de Insectos/análisis , Recombinasa Rad51/análisis , Proteína de Replicación A/análisis , Técnicas del Sistema de Dos Híbridos , Animales , Bombyx/genética , Línea Celular , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Unión Proteica , Subunidades de Proteína/análisis , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Recombinasa Rad51/genética , Recombinasa Rad51/metabolismo , Proteína de Replicación A/genética , Proteína de Replicación A/metabolismo
14.
Mol Biotechnol ; 43(1): 52-8, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19415533

RESUMEN

Gap junctions that allow for a direct exchange of second messenger and ions are the most conserved cellular structures in multicellular organisms. We have isolated and characterized a Bombyx mori gene innexin3 that encodes a new member of the innexin family required for the early embryonic development. The BmINX3 mRNA was 1,814 nucleotide residues in length, and the deduced amino acid sequence of BmInx3 shared 74% similarity with Apis melifera innexin3. The expression profile of the BmINX3 mRNA is similar to that of previously described BmINX2, expressed in ovary and testis after 5th instar larvae and in fat body after gut purge. However, during embryogenesis, the expression of BmINX3 mRNA is restricted to the blastokinesis stage. Microscopic observation of the BmInx2 and BmInx3 fused to fluorescent proteins showed an overlapping cytoplasmic expression, whereas the BmInx4 is accumulated in the cytoplasmic surface at which two cells have physical contact. This finding of innexins distribution in silkworm would provide an essential basis for future studies of the functions and interactions of innexins.


Asunto(s)
Bombyx/fisiología , Conexinas/química , Conexinas/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Regulación del Desarrollo de la Expresión Génica , Datos de Secuencia Molecular , Distribución Tisular
16.
Biotechnol Lett ; 31(4): 495-500, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19066730

RESUMEN

Tetracycline-inducible gene expression (Tet-on) system has become one of the first choices for the control of transgenes expression in mammal and drosophila. However, the Tet-on systems that have been established in mammalian system or tuned into drosophila do not function in the silkworm, Bombyx mori. To construct a functional Tet-on system in B. mori, we modified rtTA by introducing a transcription activation domain of immediate-early gene 1 of Autographa californica nuclear polyhedrosis virus and nuclear localization signal of SV40 large T-antigen. The modified rtTA can activate the transcription from 9 x tetO promoter in the silkworm cells up to 250-fold in the presence of doxycycline.


Asunto(s)
Bombyx , Doxiciclina/metabolismo , Expresión Génica , Biología Molecular/métodos , Activación Transcripcional , Animales , Antígenos Transformadores de Poliomavirus/genética , Nucleopoliedrovirus/genética , Regiones Promotoras Genéticas , Virus 40 de los Simios/genética
17.
Biosci Biotechnol Biochem ; 72(8): 1992-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18685215

RESUMEN

Cecropins belong to the antibacterial peptides family and are induced after injection of bacteria or their cell-wall components. By silkworm cDNA microarray analysis, a novel type of Cecropin family gene was identified as a cDNA up-regulated in early embryo, 1 day after oviposition. The cDNA isolated was 394 bp with 198 ORF translating 65 amino acids, encoding BmCecropin-E (BmCec-E). Using Southern hybridization and genome search analysis, the number of BmCec-E gene was estimated to be at least two per haploid, which consisted of two exons, as in other Cecropin family members. BmCec-E mRNA was expressed transiently 1 day after egg-laying (AEL, germ-band formation stage), and was specifically expressed in the degenerating intestine during the pre-pupal and pupal stages, unlike other Cecropin family genes. Immune challenge analysis showed that BmCec-E gene expression was more strongly induced by Escherichia coli (gram-negative) than by Micrococus luteus (gram-positive), and not by virus injection. By bacterial challenge, expression of BmCec-E mRNA was induced 12 h after injection, and was maintained for 24 h. Expression of BmCec-E after immune challenge was observed strongly in excretory organs, such as hindgut and malphigian, slightly in fat body, skin, and midgut.


Asunto(s)
Bombyx/metabolismo , Cecropinas/química , Cecropinas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bombyx/química , Bombyx/embriología , Bombyx/crecimiento & desarrollo , Cecropinas/genética , Cecropinas/inmunología , Clonación Molecular , Regulación del Desarrollo de la Expresión Génica , Genoma/genética , Proteínas de Insectos , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Homología de Secuencia de Aminoácido
18.
Mol Biotechnol ; 40(2): 180-5, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18543128

RESUMEN

The recombinant protein expression by Bombyx mori nucleopolyhedrovirus (BmNPV) infecting silkworm larvae or pupae may endow us with a potent system for the production of large eukaryotic proteins. However, the screening of silkworm strains ideally suited to this method has scarcely been conducted. In the present study, we injected recombinant BmNPV containing a reporter gene, luciferase or DsRed, into hemocoel of fifth instar larvae of selected 12 silkworm strains. Among them, the strain d17 is found to be the highest in reporter expression from the intrinsic polyhedrin promoter of Autographa californica NPV or the silkworm actin A3 promoter. These results suggest that the d17 strain is highly permissive for BmNPV replication and is the most likely candidate of a "factory" for large-scale expression using the BmNPV bacmid system.


Asunto(s)
Bombyx/metabolismo , Bombyx/virología , Nucleopoliedrovirus/genética , Nucleopoliedrovirus/fisiología , Animales , Bombyx/clasificación , Bombyx/genética , Expresión Génica , Genes Reporteros/genética , Larva/clasificación , Larva/genética , Larva/metabolismo , Larva/virología
19.
J Biotechnol ; 133(1): 9-17, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-17928082

RESUMEN

The promoter regions of the Bombyx mori HSC70-4 and B. mori TCTP genes characterized previously were used for the construction of a series of constitutive gene expression systems active in cultured cells. The relative abilities of these promoters were evaluated by comparing those of a silkworm actin A3 (BmActin3) promoter, which is used widely as the first choice. A series of constitutive expression systems constructed were assayed for the transcription efficiency by connecting four reporter cDNAs, firefly luciferase, 3GFP, Ds-Red, and beta-galactosidase gene using the Gateway LR reaction. The insertion of an intron enhancer into the site between the TCTP promoter and gene increased the transcription of the BmTCTP promoter by 10-fold. The insertion of the IE-1 gene and HR3 enhancer to the all three promoters were found to increase the transcription up to 560 times.


Asunto(s)
Bombyx/genética , Bombyx/metabolismo , Regiones Promotoras Genéticas/genética , Ingeniería de Proteínas/métodos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transfección/métodos , Animales
20.
J Proteome Res ; 6(6): 2295-303, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17497908

RESUMEN

The silkworm is a typical holometabolous insect going through drastic morphological changes upon metamorphosis from larvae to pupae. Comprehensive studies focusing on the changes help elucidate understanding of a biogenic mechanism. Here, we report the initial profile of the intersegmental muscle (ISM) proteins of the silkworm during larval-pupal metamorphosis. In total, 258 protein spots were resolved by two-dimensional gel electrophoresis (2-DE). Fifty-seven larval proteins were identified, where 3 proteins were exclusively detected in larval samples. Fifty-four other proteins were common in pupal samples. Of these, 12 proteins belonging to the contractile apparatus, metabolism, regulation, and signal transduction were altered in their contents during the metamorphosis from larvae to pupae. Three pupa-defective proteins were identified as isoforms of troponin I, followed by an immunoblotting validation. This data will be helpful in understanding the biochemistry of an insect ISM.


Asunto(s)
Bombyx/crecimiento & desarrollo , Metamorfosis Biológica , Proteínas Musculares/análisis , Músculo Esquelético/química , Proteómica , Animales , Bombyx/metabolismo , Electroforesis en Gel Bidimensional , Larva/química , Músculo Esquelético/crecimiento & desarrollo , Isoformas de Proteínas/análisis , Pupa/química
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