Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Eur Rev Med Pharmacol Sci ; 21(24): 5542-5547, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29271984

RESUMEN

Bone fractures are a medical condition where the continuity of the bone is broken due to a fall or accident. The fracture may also be the result of medical conditions such as osteoporosis, cancers of bone or osteogenesis imperfect. During the bone fracture healing process, the mesenchymal stem cells (undifferentiated connective tissue cells) are recruited from local and systemic sources. The modulation of mesenchymal cell migration to the fractured site is the desired goal. Still, there are many processes that are still required to be studied and analyzed. We aimed to consolidate and review the available information on this topic.


Asunto(s)
Curación de Fractura/fisiología , Células Madre Mesenquimatosas/fisiología , Animales , Movimiento Celular , Humanos , Transcripción Genética
2.
Eur Rev Med Pharmacol Sci ; 20(21): 4612-4621, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27874933

RESUMEN

With the increase of the average age of our population, the incidence of diseases specific for older adults has been increasing. One of such diseases is osteoporosis. The true incidence of osteoporosis is unknown. But the estimates indicate that this disease affects wide proportions of the population, ranging in millions or even ten millions in large countries like the United States. As this poses a significant burden on the health care system, interventions that could prevent or treat this condition are in the focus of clinical research. Vitamin D, the determinant of bone health, has been tested in clinical studies as the agent to treat osteoporosis. Despite the progress, there is still some controversy about the targeted blood levels of vitamin D, most efficient way to supplement this vitamin, and clinical efficacy of this supplementation in the elderly.In the present review, we will highlight the metabolism of vitamin D and the aforementioned unresolved issues, as well as review the recent interventional studies on vitamin D supplementation. In the present review, we will highlight the metabolism of vitamin D and the aforementioned unresolved issues, as well as review the recent interventional studies on vitamin D supplementation.


Asunto(s)
Osteoporosis/tratamiento farmacológico , Vitamina D/uso terapéutico , Anciano , Suplementos Dietéticos , Humanos , Vitamina D/sangre , Deficiencia de Vitamina D , Vitaminas/uso terapéutico
3.
Eur Rev Med Pharmacol Sci ; 20(12): 2498-504, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27383298

RESUMEN

OBJECTIVE: Talipes equinovarus is traditionally viewed in the literature as a congenital disease. CASE REPORT: We present here a case of the acquired talipes equinovarus (clubfoot) in a young adult patient that has developed the following osteomyelitis. RESULTS: We have successfully corrected this condition by fibula extension and correction of foot and ankle deformity, using external fixation device. The treatment period has extended over three years and involved two operations. CONCLUSIONS: This case report will increase awareness of adult orthopedists on acquired talipes equinovarus and propose orthopedic reconstructive strategies to rectify this condition.


Asunto(s)
Pie Equinovaro/cirugía , Osteomielitis/complicaciones , Adulto , Tobillo/patología , Alargamiento Óseo , Pie Equinovaro/etiología , Peroné/patología , Peroné/cirugía , Humanos , Pie Zambo/patología , Pie Zambo/cirugía , Adulto Joven
4.
Eur Rev Med Pharmacol Sci ; 20(12): 2505-14, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27383299

RESUMEN

Hip surgeries count to the most frequent orthopaedic operations in older patients. Nonelective surgeries for hip fractures cause substantial economic burden because of high costs of medical treatment and high associated mortality. Surgery for hip fracture in the elderly comorbid patient still presents a challenge to orthopaedic surgeons. It is recommended that this surgery is performed within 48 hours after sustaining the hip fracture to decrease mortality. Yet the recommended early surgery (i.e. 48 hours after the incident) is not always feasible due to the frequent overall frailty of the patients or conditions of concomitant disease. The care of patients unfit for early surgery has been not adequately addressed in the literature. We have previously introduced an algorithm based on ASA-PS and P-POSSUM scores to stratify elderly comorbid patients for early vs delayed hip surgery, and used principles of Damage Control Orthopaedics to minimized negative sequelae of surgery delay (Dong C et al., PLoS One 2016). In this paper, we elaborate on Damage Control Orthopaedics and the proposed approach in the context of frequent comorbidities in the elderly orthopaedic patients. Further studies on this subject are urgently needed to establish international consensus on hip fracture surgery delayed due to overall patient frailty or extensive comorbidities.


Asunto(s)
Fracturas de Cadera/cirugía , Procedimientos Ortopédicos , Anciano , Comorbilidad , Humanos , Procedimientos Ortopédicos/métodos , Procedimientos Ortopédicos/normas , Pacientes
5.
Genet Mol Res ; 12(4): 5766-73, 2013 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-24301945

RESUMEN

Prolactin (PRL) plays central roles in mammals' reproduction, gland development, milk secretion, and the expression of milk protein genes. In dairy cattle, the PRL gene is a potential quantitative trait locus and genetic marker related to milk performance traits. Here, a total of 586 randomly selected Chinese Holstein cows were genotyped for locus PRL-RsaI. One haplotype block containing eight SNPs was identified in the region from intron 3 to intron 4 of the PRL gene in Chinese Holstein cows. One tag SNP (7545 G → A) was selected to represent the haplotype block defined by the genotypic data. The cows with genotype AA of this tag SNP had a higher milk yield at 305 days (8457 ± 938 kg) than the cows with GA (7537 ± 1278 kg; P < 0.01) or GG (7757 ± 1174 kg; P < 0.05). This suggests that the haplotype block examined in this study contains important markers for milk production traits in Chinese Holstein cows.


Asunto(s)
Bovinos/genética , Lactancia/genética , Prolactina/genética , Sitios de Carácter Cuantitativo , Animales , Animales Endogámicos , Femenino , Polimorfismo de Nucleótido Simple
6.
Genet Mol Res ; 12(3): 3375-82, 2013 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-24065678

RESUMEN

The traits particularly important for milk production include milk yield, protein percentage, fat percentage, and the somatic cell score. Alpha-lactalbumin (α-LA) is an important whey protein of cow milk, and is also present in the milk of many other mammalian species. In this study, we analyzed the genetic polymorphisms of the α-LA gene and their relationship to milk production traits (milk yield, protein percentage, fat percentage, and somatic cell score) in Chinese Holstein cows. The goal of this study was to contribute further molecular genetic information related to dairy cattle, to determine the molecular markers that are most closely linked with milk production traits, and to provide a scientific basis for the improvement of economically relevant traits in cows. Fluorescence-based conformation-sensitive gel electrophoresis, DNA sequencing, and ligation detection reaction techniques were used to analyze genetic variations of the α-LA gene (5'-UTR, exons 1, 2, 3, 4, and 3'-UTR) in 923 Chinese Holstein cows. One novel single nucleotide polymorphism (SNP), α-LA2516, was identified in exon 4 of the α-LA gene. Allele frequencies were as follows: T 0.674, C 0.326. Association analysis revealed that α-LA2516 was not associated with milk yield, protein percentage, fat percentage, or somatic cell score (P > 0.05). These findings suggest that the SNP α-LA2516 in the α-LA gene likely does not have potential as a molecular marker for milk production traits in Chinese Holstein cows.


Asunto(s)
Estudios de Asociación Genética , Lactalbúmina/genética , Proteínas de la Leche/genética , Leche , Animales , Bovinos , China , Polimorfismo de Nucleótido Simple
7.
Phys Rev Lett ; 107(13): 137003, 2011 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-22026892

RESUMEN

Single-crystal neutron diffraction studies on superconductors A(2)Fe(4)Se(5), where A=Rb, Cs, (Tl, Rb), and (Tl, K) (T(c) ∼ 30 K), uncover the same Fe vacancy ordered crystal structure and the same block antiferromagnetic order as in K(2)Fe(4)Se(5). The Fe order-disorder transition occurs at T(S)=500-578 K, and the antiferromagnetic transition at T(N) = 471-559 K with an ordered magnetic moment ∼3.3µ(B)/Fe at 10 K. Thus, all recently discovered A intercalated iron selenide superconductors share the common crystalline and magnetic structure, which are very different from previous families of Fe-based superconductors, and constitute a distinct new 245 family.

8.
Opt Lett ; 36(18): 3630-2, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21931414

RESUMEN

A broadband integrated waveguide polarization beam splitter consisting of a metal nanoribbon and two dielectric waveguides is proposed and numerically investigated. This surface plasmon based device provides a unique approach for polarization sensitive manipulation of light in an integrated circuit and will be essential for future classical and quantum information processes.

9.
J Ind Microbiol Biotechnol ; 38(8): 1027-35, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20922458

RESUMEN

Ophiocordyceps sinensis (≡Cordyceps sinensis) is one of the best known traditional Chinese medicines, with great benefits to human health and huge economic value. The reliability of fungal materials used in studies of the species is particularly important because contradictory results have been found in various studies in the past decades. Examination of fungal materials specified in reports on O. sinensis showed great variation in both sources and culture conditions of living strains. To test the reliability of the materials used, experiments were carried out to study the effect of culture conditions on the growth of living strains of O. sinensis by using six reliable strains representing the major production regions of the fungus on the Tibetan Plateau. The results showed that O. sinensis is a slow-growing fungus at comparatively low temperature, and that temperature and growth period are crucial factors which can be verified by experiment. Analyses of fungal materials used in 152 papers on O. sinensis from PubMed since 1998 showed that 41 papers lacked detailed information on the fungal materials; 26 used natural products, 11 used artificially cultivated fruit bodies, and 80 used fermentation products from living strains. Of the latter category (using fermentation products), 64 of the papers were found to use unreliable (45) or uncertain (19) strains for fermentation products based on the temperature and growth period for O. sinensis strains verified in this study. Apart from the natural products of O. sinensis, which require scientific identification, a total of at least 116 papers (over three-quarters) used unreliable, uncertain or unspecified materials, including so-called cultivated fruit bodies which were apparently from other species. The reliability of materials or living strains used in studies on O. sinensis is discussed in this paper, and suggestions are made for use of reliable fungal materials in further studies of this fungus.


Asunto(s)
Cordyceps/crecimiento & desarrollo , Secuencia de Bases , Cordyceps/clasificación , Cordyceps/genética , Medios de Cultivo , Fermentación , Hypocreales , Técnicas Microbiológicas , Datos de Secuencia Molecular , Reproducibilidad de los Resultados
10.
Opt Lett ; 34(4): 509-11, 2009 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19373357

RESUMEN

We experimentally report an asymmetrical spherical microcavity with thermal-induced deformation, in which five-bounce whispering-gallery modes possess not only ultrahigh quality factors (Q) but also remarkably directional escape emission from the microsphere boundary. With efficient free-space excitation and collection, a low-threshold microlaser is demonstrated and exhibits a highly directional emission. Our measurement agrees well with the theoretical predictions by corrected Fresnel law.

11.
Lebensm Wiss Technol ; 41(4): 669-677, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-32287390

RESUMEN

Cordyceps sinensis, one of the best known traditional Chinese medicines and health foods, has been highly valued for the treatment of a wide range of diseases and reported to have antioxidant properties. In the present study, the antioxidant activities of hot-water extracts from natural and cultured mycelia of C. sinensis were investigated and evaluated using six in vitro assays, including inhibition of linoleic acid peroxidation; scavenging abilities on DPPH•, hydroxyl and superoxide anion radicals; the reducing power and the chelating ability on ferrous ions. Among these assays, the extracts showed the best effect on the inhibition of linoleic peroxidation with the lowest IC50 values and with an inhibition rate over 90% at concentration of 0.8-1.6 mg/ml, more stable than that of α-tocopherol, a recognised natural antioxidant. The scavenging activities on superoxide anion and hydroxyl radicals of the two extracts were slightly lower than that of butylated hydroxytoluene. DPPH• scavenging activities of both extracts reached over 80% inhibition at 4-8 mg/ml. Both extracts showed moderate reducing power and ferrous ion chelating activity. The IC50 value of the extract from cultured mycelia in all the tests, except for linoleic acid peroxidation, was significantly lower than that of natural mycelia. There was no evident correlation between the antioxidant activity and the content of protein, polysaccharides and mannitol of extracts from C. sinensis; the antioxidant activity may be due to a combined effect of these or some other compounds. These results suggested that both the extracts from cultured and natural mycelia have direct and potent antioxidant activities and that the cultured mycelia of the fungus could be used for the antioxidant activity to reduce the human demands on the natural resources of the fungus, an endangered species.

12.
Cell Prolif ; 39(6): 507-18, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17109635

RESUMEN

Herpes simplex virus (HSV)-1 stimulation-related gene 1 (HSRG1) protein expression is induced in HSV-1 infected cells. We found that HSRG1 interacts with SV40 large T antigen (LT) in yeast two-hybrid assay and bimolecular fluorescence complementation (BiFC) assay. This interaction alters LT's regulation of the SV40 promoter and its ability to influence the cell cycle. Choramphenicol acetyl-transferase (CAT) assays revealed that initiation of gene transcription by LT is changed by HSRG1 expression. HSRG1 inhibits the ability of LT to activate SV40 late gene transcription. Further data indicate that the ability of LT protein to stimulate S-phase entry is also inhibited by the expression of HSRG1. The results of a colony-forming assay suggested that expression of HSRG1 in cells transfected by LT gene decreased the rate of colony formation. Yeast two-hybrid beta-galactosidase assay revealed that amino acid residues 132-450 in LT bind HSRG1.


Asunto(s)
Antígenos Transformadores de Poliomavirus/genética , Antígenos Transformadores de Poliomavirus/metabolismo , Proteínas/metabolismo , Animales , División Celular , Chlorocebus aethiops , Fibroblastos/citología , Fibroblastos/fisiología , Humanos , Péptidos y Proteínas de Señalización Intracelular , Regiones Promotoras Genéticas/fisiología , Mapeo de Interacción de Proteínas , Fase S , Virus 40 de los Simios/genética , Transcripción Genética , Transfección , Técnicas del Sistema de Dos Híbridos , Células Vero
13.
Theor Appl Genet ; 113(3): 397-406, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16758190

RESUMEN

PCR technique was employed to isolate gene homologous to the MS2Bnap (X99922.1) from two rapeseed (Brassica napus L.) dominant digenic male sterile lines, namely 220A (male sterile) and 220B (male fertile), 6A (male sterile) and 6C (male fertile). The isolated 2,581 bp sequences from 220A (named 220A-gDNA, GenBank accession number AY288778), 220B (220B-gDNA, AY257490), 6A (6A-gDNA, DQ060318) and 6C (6C-gDNA, DQ060319) all contained six introns. Forty-one single nucleotide polymorphism (SNP) sites were detected by alignment of these four sequences, seven of them dispersed in the exon regions. Two SNPs (1247, 1656) were detected between 220A-gDNA and 220B-gDNA, and the one at nucleotide 1247 of 220A-gDNA with A replaced by C was a missense mutation, which may be the putative male sterility site in 220A. All eight SNPs identified between 6A-gDNA and 6C-gDNA were located in the third intron, so the proteins encoded by them are the same. The one SNP between 6A-/6C-gDNA and 220A-/220B-gDNA at nucleotide 2474 of 220A-/220B-gDNA with C replaced by G was a missense mutation. Mutation site of BNMS2PROT (CAA68190.1) encoded by MS2Bnap in 220A(254) and 6A/6C(584) is different, which indicated dominant digenic male sterile line 220AB and 6CA have some difference in the molecular level. Comparison of structure of MS2Bnap in B. napus with that of MS2 in Arabidopsis thaliana revealed that the similarity of exons between these two genes is higher than that of introns.


Asunto(s)
Brassica napus/genética , Infertilidad Vegetal , Proteínas de Plantas/genética , Secuencia de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Secuencia de Bases , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico
14.
Cell Prolif ; 39(2): 93-103, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16542345

RESUMEN

A type II membrane protein similar to CD69 (TIIMPSC) has been isolated in human embryo fibroblasts treated with IFN-alpha. Structural analysis and immunofluorescence detection has suggested that this protein is located on the surface of fibroblasts, generally considered, a receptor. Cell proliferation assay has revealed that activation of TIIMPSC elevates the level of fibroblast proliferation. Further, examination of signal transduction has indicated that expression of this protein is up-regulated by IFN-alpha stimulation, and that it is involved in the regulation of fibroblast growth through the JAK-STAT signalling pathway.


Asunto(s)
Antígenos CD/química , Antígenos de Diferenciación de Linfocitos T/química , Proliferación Celular , Fibroblastos/metabolismo , Interferón-alfa/farmacología , Proteínas de la Membrana/fisiología , Receptores de Superficie Celular/fisiología , Factores de Transcripción STAT/fisiología , Secuencia de Bases , Línea Celular , Técnica del Anticuerpo Fluorescente , Humanos , Factor 3 de Genes Estimulados por el Interferón/fisiología , Lectinas Tipo C , Glicoproteínas de Membrana , Proteínas de la Membrana/química , Proteínas de la Membrana/aislamiento & purificación , Datos de Secuencia Molecular , Fosforilación , Receptores de Superficie Celular/química , Receptores de Superficie Celular/aislamiento & purificación , Transducción de Señal , Regulación hacia Arriba
15.
J Appl Microbiol ; 99(3): 483-92, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16108789

RESUMEN

AIMS: The nutritional requirements for mycelial growth of Cordyceps sinensis in semi-synthetic liquid media were investigated. The results provide a basis for further physiological study and industrial fermentation of the fungus. METHODS AND RESULTS: Nutritional requirements, including 17 carbohydrates, 16 nitrogen compounds, nine vitamins, four macro-elements, four trace-elements and eight ratios of carbon to nitrogen, were studied for their effects on the mycelial growth in submerged cultures of C. sinensis by using one-factor-at-a-time and orthogonal matrix methods. Among these variables, sucrose, peptone, folic acid, calcium, zinc and a carbon to nitrogen ratio 12 : 1 were identified as the requirements for the optimum mycelial growth. The concentrations of sucrose, peptone and yeast extract were optimized and the effects of medium composition on mycelial growth were found to be in the order sucrose > yeast extract > peptone. The optimal concentration for mycelial growth was determined as 50 g l(-1) sucrose, 10 g l(-1) peptone and 3 g l(-1) yeast extract. CONCLUSIONS: Under optimal culture conditions, over 22 g l(-1) of mycelial biomass could be obtained after 40 days in submerged cultures. SIGNIFICANCE AND IMPACT OF THE STUDY: Cordyceps sinensis, one of the most valued medicinal fungi, is shown to grow in axenic culture. This is the first report on nutritional requirements and design of a simplified semi-synthetic medium for mycelial growth of this psychrophilic species, which grows slowly below 20 degrees C. The results of this study will facilitate research on mass production of the fungus under defined culture conditions.


Asunto(s)
Cordyceps/crecimiento & desarrollo , Micelio/crecimiento & desarrollo , Fenómenos Fisiológicos de la Nutrición/fisiología , Carbohidratos/fisiología , Carbono/fisiología , Medios de Cultivo , Elementos Químicos , Nitrógeno/fisiología , Compuestos de Nitrógeno/metabolismo , Peptonas/metabolismo , Sacarosa/metabolismo , Vitaminas/fisiología , Levaduras/metabolismo
16.
Plant Cell ; 13(6): 1333-46, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11402164

RESUMEN

Based mostly on the results of in vitro experiments, ADF (actin-depolymerizing factor) proteins are thought to be key modulators of the dynamic organization of the actin cytoskeleton. The few studies concerned with the in vivo function of ADF proteins that have been reported to date were performed almost exclusively using single-cell systems and have failed to produce consistent results. To investigate ADF functions in vivo and during the development of multicellular organs, we generated transgenic Arabidopsis plants that express a cDNA encoding an ADF protein (AtADF1) in the sense or the antisense orientation under the control of a strong constitutively active promoter. Selected lines with significantly altered levels of AtADF protein expression were characterized phenotypically. Overexpression of AtADF1 resulted in the disappearance of thick actin cables in different cell types, caused irregular cellular and tissue morphogenesis, and reduced the growth of cells and organs. In contrast, reduced AtADF expression promoted the formation of actin cables, resulted in a delay in flowering, and stimulated cell expansion as well as organ growth. These results are consistent with the molecular functions of ADF as predicted by in vitro studies, support the global roles of ADF proteins during the development of a multicellular organism, and demonstrate that these proteins are key regulators of F-actin organization, flowering, and cell and organ expansion in Arabidopsis.


Asunto(s)
Actinas/metabolismo , Arabidopsis/fisiología , Proteínas de Microfilamentos/fisiología , Proteínas de Plantas/fisiología , Factores Despolimerizantes de la Actina , Actinas/química , Arabidopsis/crecimiento & desarrollo , División Celular , Destrina , Hipocótilo/citología , Hipocótilo/ultraestructura , Plantas Modificadas Genéticamente
17.
Plant Mol Biol ; 45(5): 517-27, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11414611

RESUMEN

Actin depolymerizing factor (ADF) is a key regulator of the organization of the actin cytoskeleton during various cellular activities. We found that ADF genes in Arabidopsis form a large family consisting of at least nine members, four of which were cloned and sequenced in this study. Comparison of genomic and cDNA sequences showed that the AtADF1, AtADF5, and AtADF6 genes all contain two introns at conserved positions. Analysis of transgenic Arabidopsis plants carrying promoter-GUS fusion constructs revealed that AtADF1 and AtADF6 are expressed in the vascular tissues of all organs, whereas expression of AtADF5 is restricted to the root tip meristem. GFP-AtADFI, GFP-AtADF5, and GFP-AtADF6 fusion proteins were found to bind to actin filaments in vivo, and to reorganize the actin cytoskeleton when transiently expressed in plant cells.


Asunto(s)
Actinas/metabolismo , Arabidopsis/genética , Proteínas del Citoesqueleto/genética , Proteínas de Microfilamentos/genética , Factores Despolimerizantes de la Actina , Secuencia de Aminoácidos , Arabidopsis/metabolismo , Northern Blotting , Clonación Molecular , Proteínas del Citoesqueleto/metabolismo , Destrina , Etiquetas de Secuencia Expresada , Glucuronidasa/genética , Glucuronidasa/metabolismo , Proteínas Fluorescentes Verdes , Intrones , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Proteínas de Microfilamentos/metabolismo , Microscopía Fluorescente , Datos de Secuencia Molecular , Estructuras de las Plantas/anatomía & histología , Estructuras de las Plantas/metabolismo , ARN Mensajero/análisis , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Alineación de Secuencia
18.
Plant Physiol ; 124(4): 1637-47, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11115881

RESUMEN

Profilin (PFN) is an ubiquitous, low-M(r), actin-binding protein involved in the organization of the cytoskeleton of eukaryotes including higher plants. PFNs are encoded by a multigene family in Arabidopsis. We have analyzed in vivo functions of Arabidopsis PFN by generating transgenic plants carrying a 35S-PFN-1 or 35S-antisense PFN-1 transgene. Etiolated seedlings underexpressing PFN (PFN-U) displayed an overall dwarf phenotype with short hypocotyls whose lengths were 20% to 25% that of wild type (WT) at low temperatures. Light-grown PFN-U plants were smaller in stature and flowered early. Compared with equivalent cells in WT, most cells in PFN-U hypocotyls and roots were shorter, but more isodiametric, and microscopic observations of etiolated PFN-U hypocotyls revealed a rough epidermal surface. In contrast, light-grown seedlings overexpressing PFN had longer roots and root hair although etiolated seedlings overexpressing PFN were either the same size or slightly longer than WT seedlings. Transgenic seedlings harboring a PFN-1-GUS transgene directed expression in root and root hair and in a ring of cells at the elongating zone of the root tip. As the seedlings matured PFN-1-GUS was mainly expressed in the vascular bundles of cotyledons and leaves. Our results show that Arabidopsis PFNs play a role in cell elongation, cell shape maintenance, polarized growth of root hair, and unexpectedly, in determination of flowering time.


Asunto(s)
Arabidopsis/crecimiento & desarrollo , Proteínas Contráctiles , Proteínas de Microfilamentos/fisiología , Actinas/metabolismo , Arabidopsis/citología , Arabidopsis/genética , Proteínas de Arabidopsis , Regulación de la Expresión Génica de las Plantas , Hipocótilo/genética , Hipocótilo/crecimiento & desarrollo , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Microscopía Electrónica de Rastreo , Fenotipo , Desarrollo de la Planta , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Plantas/genética , Plantas/ultraestructura , Plantas Modificadas Genéticamente , Profilinas , ARN de Planta/genética , ARN de Planta/metabolismo , Factores de Tiempo , Distribución Tisular
20.
Plant J ; 10(2): 269-79, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8771785

RESUMEN

Four members of the Arabidopsis profilin (pfn) multigene family have been cloned, sequenced and analyzed. By RNA gel blot analysis it has been shown that these four genes fall into two groups: one group (pfn1 and pfn2) is expressed in all organs of the plant and the other group (pfn3 and pfn4) in floral tissues only. Based on amino acid sequence alignment Arabidopsis profilins can be divided into the same two groups: PFN1 and PFN2 are 89% identical and PFN3 and PFN4 are 91% identical. Between these two groups they are 71-75% identical. The Arabidopsis profilins bind poly-L-proline and can complement both the Saccharomyces cerevisiae profilin deletion mutant and the Schizosaccharomyces pombe cdc3-124/profilin mutation, showing that the plant profilins are functionally similar to yeast profilins despite the low amino acid sequence homology. Analysis of pfn promoter-GUS fusion genes in transgenic Arabidopsis shows that pfn2 is specifically expressed in the vascular bundles of roots, hypocotyls, cotyledons, leaves, sepals, petals, stamen filaments and stalks of developing seeds, whereas expression of pfn4 is restricted to mature and germinating pollen grains.


Asunto(s)
Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas Contráctiles , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Secuencia de Aminoácidos , Proteínas de Arabidopsis , Clonación Molecular , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Eliminación de Gen , Regulación de la Expresión Génica de las Plantas , Genes Fúngicos , Genes de Plantas , Prueba de Complementación Genética , Datos de Secuencia Molecular , Familia de Multigenes , Plantas Modificadas Genéticamente , Polen/genética , Polen/metabolismo , Profilinas , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Homología de Secuencia de Aminoácido
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA