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1.
Temporal and spatial expression of a thiolprotease gene during pea ovary senescence, and its regulation by gibberellin 总被引:3,自引:0,他引:3
A. Granell N. Harris A. G. Pisabarro J. Carbonell 《The Plant journal : for cell and molecular biology》1992,2(6):907-915
Clones encoding a thiolprotease (tpp) have been isolated from a cDNA library of unpollinated, senescent pea ovaries and its pattern of expression during both ovary senescence and parthenocarpic development have been studied. The sequence of the tpp cDNA displays a high similarity with other plant and animal thiolproteases of the papain group. The homology is highest around the Cys-His of the active centre; a 109 amino acid sequence at the carboxy terminus was found to be homologous only to thiolproteases of plant origin; this part of the mRNA is also present in another pea mRNA that exhibits similar patterns of induction. tpp mRNA shows a temporal pattern of accumulation that precedes that observed for proteolytic activity. Such accumulation did not occur when ovaries were induced to grow parthenocarpically by gibberellic acid (GA) treatment; furthermore the initial low level of expression present in ovaries decreased after GA treatment, indicating that the gene is down-regulated by gibberellins. Spatially, tpp mRNA is localized mainly within the ovule and ovary vascular elements, and transiently within the endocarp of senescent ovaries. This pattern of expression precedes the development of the cytopathogenic effects observed as unpollinated ovaries undergo senescence. 相似文献
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Floral development and expression of floral homeotic genes are influenced by cytokinins 总被引:4,自引:1,他引:3
J.J. Estruch A. Granell G. Hansen E. Prinsen P. Redig H. Van Onckelen Z. Schwarz-Sommer H. Sommer A. Spena 《The Plant journal : for cell and molecular biology》1993,4(2):379-384
Tobacco plants that are somatic mosaics for the expression of a cytokinin-synthesizing gene have viviparous leaves. Epiphyllous buds can be either vegetative or floral. Floral adventitious buds can be either normal or abnormal. Abnormalities of floral development correlate with: (i) a local activation of the cytokinin-synthesizing gene, (ii) a drastic increase in floral cytokinin content, and (iii) a decrease in the steady-state levels of mRNA homologues of the homeotic genes DEFA , GLO and PLENA of Antirrhinum majus . Thus, these data show in planta that cytokinins, a class of phytohormones, are able to alter the development of floral organs and to decrease the expression of three homeotic floral genes. 相似文献
4.
Twelve cDNAs corresponding to mRNAs inducible by ethylene were isolated by differential screening of a cDNA library from ethylene-treated Citrus sinensis fruits. Northern analysis of RNA extracted from flavedo of ethylene-treated fruits and from fruits at different maturation stages showed that some of the mRNAs corresponding to these cDNAs were regulated both by ethylene treatment and during fruit maturation. The effect of exogenous ethylene on leaves and of endogenous ethylene on flowers showed that gene induction was not restricted to the flavedo tissue. The possible role of ethylene during maturation of the non-climacteric Citrus fruit is discussed. 相似文献
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Gabriela Oses Albert Biete Diego Muoz-Guglielmetti Carla Cases Tanny Daniela Barreto Angeles Rovirosa Aureli Torn Jaume Pahisa Pere Fust Ramn Rull Antonio Herreros Jordi Sez Meritxell Moll 《Reports of Practical Oncology and Radiotherapy》2022,27(5):905
BackgroundSalvage surgery is considered an option for isolated recurrences of retroperitoneal and pelvic tumors, in patients who have undergone previous radiotherapy. In order to increase local control intra operative electron radiation therapy (IOERT) can be used in these patients to administer additional radiation dose. We evaluated the outcomes and adverse effects in patients with retroperitoneal sarcoma and gynecologic tumors after salvage surgery and IOERT.Materials and methodsTwenty patients were retrospectively analyzed. Twenty-three IOERT treatments were performed after surgery. Six (30%) were sarcoma and 14 (70%) were gynecological carcinoma. Administered dose depended on previous dose received with external beam radiotherapy (EBRT) and proximity to critical structures. The toxicities were scored using the Common Terminology Criteria for Adverse Events version 4.0.ResultsThe median age of the patients was 51 years (range 34–70). After a median follow-up of 32 months (range 1–68), in the sarcoma group the local control rate was 66.6%; while in the gynecological group the local control rate was 64.3%. In relation to late toxicity, one patient had a Grade 2 vesicovaginal fistula, and one patient presented Grade 4 enterocolitis and enteric intestinal fistula.ConclusionsIOERT could have a role in the treatment of retroperitoneal sarcomas in primary tumors after EBRT, as it may suggest a benefit in local control or recurrences after surgical resection in those at high risk of microscopic residual disease. The addition of IOERT to salvage resection for isolated recurrence of gynecologic cancers suggest favorable local control in cases with concern for residual microscopic disease. 相似文献
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Genetic and morphological differentiation between the two largest breeding colonies of Audouin's Gull Larus audouinii 总被引:1,自引:0,他引:1
We assessed the genetic and morphological differences between the two largest breeding colonies of Audouin's Gull Larus audouinii , an endemic seabird species of the Mediterranean region. The two colonies comprise c. 75% of the total world population and are 655 km apart. The Ebro Delta colony was formed recently and, after dramatic growth mainly due to high rates of both immigration and reproductive success, is now the largest in the world (more than 60% of the total population). The Chafarinas Islands support an ancient colony with relatively little fluctuation in breeding numbers. The two colonies also differ greatly in environmental conditions, with the Ebro Delta being a higher quality breeding site. Very little movement occurs between the two colonies. We collected morphological data and blood samples from both colonies. Polymorphic microsatellite markers were used to study the genetic differentiation. These showed no significant variation between colonies, nor evidence of a founder effect in the Ebro Delta. Individuals from the Ebro Delta were larger than those from Chafarinas, the difference being greater for males. This probably reflects a stronger male susceptibility to worse environmental conditions during chick growth at the Chafarinas Islands. 相似文献
9.
bel Vrtesy Oliver L Eichmüller Julia Naas Maria Novatchkova Christopher Esk Meritxell Balmaa Sabrina Ladstaetter Christoph Bock Arndt von Haeseler Juergen A Knoblich 《The EMBO journal》2022,41(17)
Organoids enable in vitro modeling of complex developmental processes and disease pathologies. Like most 3D cultures, organoids lack sufficient oxygen supply and therefore experience cellular stress. These negative effects are particularly prominent in complex models, such as brain organoids, and can affect lineage commitment. Here, we analyze brain organoid and fetal single‐cell RNA sequencing (scRNAseq) data from published and new datasets, totaling about 190,000 cells. We identify a unique stress signature in the data from all organoid samples, but not in fetal samples. We demonstrate that cell stress is limited to a defined subpopulation of cells that is unique to organoids and does not affect neuronal specification or maturation. We have developed a computational algorithm, Gruffi, which uses granular functional filtering to identify and remove stressed cells from any organoid scRNAseq dataset in an unbiased manner. We validated our method using six additional datasets from different organoid protocols and early brains, and show its usefulness to other organoid systems including retinal organoids. Our data show that the adverse effects of cell stress can be corrected by bioinformatic analysis for improved delineation of developmental trajectories and resemblance to in vivo data. 相似文献
10.
Jose C. E. Serrano David De Lorenzo Anna Cassanye Meritxell Martín-Gari Alberto Espinel Marco Antonio Delgado Reinald Pamplona Manuel Portero-Otin 《Genes & nutrition》2013,8(6):561-569
Vitamin D receptor polymorphisms may predispose that not all individuals could have benefits from the nutritional supplementation of 25-hydroxyvitamin D. Furthermore, vitamin D-related cardiovascular effects may also be influenced by soy isoflavones considered endocrine regulators of cardiovascular homeostasis. To find possible gene–diet interactions by evaluating individualized lipid metabolism benefits from an increase in soy and 25-hydroxyvitamin D intake, 106 healthy individuals, genotyped for vitamin D receptor (VDR) gene polymorphism rs1544410 (BsmI) were randomly assigned to either no intake, to daily 250?mL or 500?mL of a 25-hydroxyvitamin D supplemented SB for 2 months. The soybean beverage induced differences in cardiovascular risk factors (lipid profile, blood pressure, TNFα and MCP-1), as well as vitamin D metabolites in a dose-gene-dependent relation. Thus, VDR BsmI polymorphism affected individual response being the GG genotype the ones that showed dose-dependent manner responsiveness in the reduction in total cholesterol, LDL and triglycerides in comparison with the AA/AG genotype. These differences were associated with increased plasma levels of 1α,25-dyhydroxyvitamin D3 in the carriers of the GG genotype. It was concluded that metabolic response to 25-hydroxyvitamin D and soybean supplementation is dependent on VDR BsmI GG genotype due to a higher conversion rate from vitamin D precursors. 相似文献