共查询到20条相似文献,搜索用时 31 毫秒
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Vesna Nikolova-Krstevski Lei Yuan Alexandra Le Bras Preethi Vijayaraj Maiko Kondo Isabel Gebauer Manoj Bhasin Chris V Carman Peter Oettgen 《BMC developmental biology》2009,9(1):1-14
Background
During skeletogenesis, protein levels of β-catenin in the canonical Wnt signaling pathway determine lineage commitment of skeletal precursor cells to osteoblasts and chondrocytes. Adenomatous polyposis coli (Apc) is a key controller of β-catenin turnover by down-regulating intracellular levels of β-catenin.Results
To investigate whether Apc is involved in lineage commitment of skeletal precursor cells, we generated conditional knockout mice lacking functional Apc in Col2a1-expressing cells. In contrast to other models in which an oncogenic variant of β-catenin was used, our approach resulted in the accumulation of wild type β-catenin protein due to functional loss of Apc. Conditional homozygous Apc mutant mice died perinatally showing greatly impaired skeletogenesis. All endochondral bones were misshaped and lacked structural integrity. Lack of functional Apc resulted in a pleiotropic skeletal cell phenotype. The majority of the precursor cells lacking Apc failed to differentiate into chondrocytes or osteoblasts. However, skeletal precursor cells in the proximal ribs were able to escape the noxious effect of functional loss of Apc resulting in formation of highly active osteoblasts. Inactivation of Apc in chondrocytes was associated with dedifferentiation of these cells.Conclusion
Our data indicate that a tight Apc-mediated control of β-catenin levels is essential for differentiation of skeletal precursors as well as for the maintenance of a chondrocytic phenotype in a spatio-temporal regulated manner. 相似文献2.
Background
Spinal disorders are a major cause of disability for humans and an important health problem for intensively farmed animals. Experiments have shown that vertebral deformities present a complex but comparable etiology across species. However, the underlying molecular mechanisms involved in bone deformities are still far from understood. To further explicate the mechanisms involved, we have examined the fundamental aspects of bone metabolism and pathogenesis of vertebral fusions in Atlantic salmon (Salmo salar). 相似文献3.
Kevin CR Kerr Sharon M Birks Mikhail V Kalyakin Yaroslav A Red'kin Eugeny A Koblik Paul DN Hebert 《Frontiers in zoology》2009,6(1):1-13
Background
Many fish species experience long periods of fasting in nature often associated with seasonal reductions in water temperature and prey availability or spawning migrations. During periods of nutrient restriction, changes in metabolism occur to provide cellular energy via catabolic processes. Muscle is particularly affected by prolonged fasting as myofibrillar proteins act as a major energy source. To investigate the mechanisms of metabolic reorganisation with fasting and refeeding in a saltwater stage of Atlantic salmon (Salmo salar L.) we analysed the expression of genes involved in myogenesis, growth signalling, lipid biosynthesis and myofibrillar protein degradation and synthesis pathways using qPCR.Results
Hierarchical clustering of gene expression data revealed three clusters. The first cluster comprised genes involved in lipid metabolism and triacylglycerol synthesis (ALDOB, DGAT1 and LPL) which had peak expression 3-14d after refeeding. The second cluster comprised ADIPOQ, MLC2, IGF-I and TALDO1, with peak expression 14-32d after refeeding. Cluster III contained genes strongly down regulated as an initial response to feeding and included the ubiquitin ligases MuRF1 and MAFbx, myogenic regulatory factors and some metabolic genes.Conclusion
Early responses to refeeding in fasted salmon included the synthesis of triacylglycerols and activation of the adipogenic differentiation program. Inhibition of MuRF1 and MAFbx respectively may result in decreased degradation and concomitant increased production of myofibrillar proteins. Both of these processes preceded any increase in expression of myogenic regulatory factors and IGF-I. These responses could be a necessary strategy for an animal adapted to long periods of food deprivation whereby energy reserves are replenished prior to the resumption of myogenesis. 相似文献4.
Elisabeth Ytteborg Anne Vegusdal P. Eckhard Witten Gerd Marit Berge Harald Takle Tone-Kari Østbye Bente Ruyter 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2010,1801(2):127-137
The formation and mineralisation of bone are two critical processes in fast-growing Atlantic salmon (Salmo salar). The mechanisms of these processes, however, have not been described in detail. Thus, in vitro systems that allow the study of factors that influence bone formation in farmed Atlantic salmon are highly warranted. We describe here a method by which unspecialised primary cells from salmon white muscle can differentiate to osteoblasts in vitro. We have subsequently used the differentiated cells as a model system to study the effects of two factors that influence bone formation in Atlantic salmon under commercial farming conditions, namely polyunsaturated fatty acids, PUFAs, and temperature. Muscle precursor cells changed their morphology from triangular or spindle-shaped cells to polygonal or cubical cells after 3 weeks in osteogenic medium. In addition, gene expression studies showed that marker genes for osteoblastogenesis; alp, col1a1, osteocalcin, bmp2 and bmp4 increased after 3 weeks of incubation in osteogenic media showing that these cells have differentiated to osteoblasts at this stage. Adding CLA or DHA to the osteoblast media resulted in a reduced PGE2 production and increased expression of osteocalcin. Further, temperature studies showed that differentiating osteoblasts are highly sensitive to increased incubation temperature at early stages of differentiation. Our studies show that unspecialised precursor cells isolated from salmon muscle tissue can be caused to differentiate to osteoblasts in vitro. Furthermore, this model system appears to be suitable for the study of osteoblast biology in vitro. 相似文献
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Wen-Chao Li Rui-Jiang Xu Yi-Long Xue Jing-Xiang Huang Yu-Hong Gao 《Biotechnology and Bioprocess Engineering》2013,18(4):655-662
Background
Tissue-engineered cartilage has provided a promising method in the treatment of physeal growth arrest. This study was designed to investigate transplantation of microencapsulated allogeneic chondrocytes to treat the injured growth plate.Methods
Allogeneic chondrocytes were encapsulated within alginate-polylysinealginate semipermeable membranes. Microencapsulated chondrocytes co-cultured with Bone Mesenchymal Stem Cells (BMSCs) were evaluated whether it could promote chondrogenesis of BMSCs. An experiment model of an injured growth plate was made by resecting the lateral half of the right distal femur physis in rabbits. Microencapsulated allogeneic chondrocytes, allogeneic chondrocytes as well as empty microcapsules were grafted into growth plate defects of 6-week-old rabbits. Histological and radiographic examinations were examined after transplantation up to 16 weeks.Results
The histological study showed that BMSCs co-cultured with microencapsulated chondrocytes could produce GAG and II collagen similarly with chondrocytes. Angular deformity and length discrepancy in the group with microencapsulated allogeneic chondrocytes were less than those in other groups (p < 0.001). The histological study confirmed the viability of microencapsulated chondrocytes at 16 weeks postoperatively. The neogenetic chondrocytes of columnar arrangement have been found in the growth plate defect to prevent early ossification and closure of the growth plate.Conclusions
The histological study confirmed the viability of microencapsulated chondrocytes at 16 weeks postoperatively. The neogenetic chondrocytes of columnar arrangement have been found in the growth plate defect to prevent early ossification and closure of the growth plate. 相似文献6.
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Frank Entschladen Joachim Altschmied Ria Baumgrass Iris Behrmann Klaudia Giehl Heike Hermanns Otmar Huber Arnd Kieser Lars-Oliver Klotz Katharina F Kubatzky Ralf Hass Ottmar Janssen Karlheinz Friedrich 《Cell communication and signaling : CCS》2010,8(1):1-7
Background
The purpose of this study is to determine whether isolated suspension mouse peripheral mononucleated blood cells have the potential to differentiate into two distinct types of cells, i.e., osteoblasts and osteoclasts.Results
Differentiation into osteoblast cells was concomitant with the activation of the Opn gene, increment of alkaline phosphatase (ALP) activity and the existence of bone nodules, whereas osteoclast cells activated the Catk gene, increment of tartrate resistant acid phosphatase (TRAP) activity and showed resorption activities via resorption pits. Morphology analyses showed the morphology of osteoblast and osteoclast cells after von Kossa and May-Grunwald-Giemsa staining respectively.Conclusions
In conclusion, suspension mononucleated cells have the potentiality to differentiate into mature osteoblasts and osteoclasts, and hence can be categorized as multipotent stem cells. 相似文献8.
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Takeuchi R Ryo A Komitsu N Mikuni-Takagaki Y Fukui A Takagi Y Shiraishi T Morishita S Yamazaki Y Kumagai K Aoki I Saito T 《Arthritis research & therapy》2008,10(4):R77-11
Introduction
The effect of low-intensity pulsed ultrasound (LIPUS) on cell growth was examined in three-dimensional-cultured chondrocytes with a collagen sponge. To elucidate the mechanisms underlying the mechanical activation of chondrocytes, intracellular signaling pathways through the Ras/mitogen-activated protein kinase (MAPK) and the integrin/phosphatidylinositol 3 kinase (PI3K)/Akt pathways as well as proteins involved in proliferation of chondrocytes were examined in LIPUS-treated chondrocytes.Methods
Articular cartilage tissue was obtained from the metatarso-phalangeal joints of freshly sacrificed pigs. Isolated chondrocytes mixed with collagen gel and culture medium composites were added to type-I collagen honeycomb sponges. Experimental cells were cultured with daily 20-minute exposures to LIPUS. The chondrocytes proliferated and a collagenous matrix was formed on the surface of the sponge. Cell counting, histological examinations, immunohistochemical analyses and western blotting analysis were performed.Results
The rate of chondrocyte proliferation was slightly but significantly higher in the LIPUS group in comparison with the control group during the 2-week culture period. Western blot analysis showed intense staining of type-IX collagen, cyclin B1 and cyclin D1, phosphorylated focal adhesion kinase, and phosphorylated Akt in the LIPUS group in comparison with the control group. No differences were detected, however, in the MAPK, phosphorylated MAPK and type-II collagen levels.Conclusion
LIPUS promoted the proliferation of cultured chondrocytes and the production of type-IX collagen in a three-dimensional culture using a collagen sponge. In addition, the anabolic LIPUS signal transduction to the nucleus via the integrin/phosphatidylinositol 3-OH kinase/Akt pathway rather than the integrin/MAPK pathway was generally associated with cell proliferation. 相似文献13.
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Hua Zhang Lian Duan Ji-Song Dai Chang-Quan Zhang Juan Li Ming-Hong Gu Qiao-Quan Liu Ying Zhu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(2):273-282
Key message
We discovered four QTLs that maintain proper rice amylose content at high temperature by increasing the splicing efficiency of Wx gene.Abstract
Amylose content mainly controlled by Wx gene is a key physicochemical property for eating and cooking quality in rice. During the grain filling stage, high temperature can harm rice grain quality by significantly reducing the amylose content in many rice varieties. Here, we provide genetic evidences between Wx gene expression and rice amylose content at high temperature, and identified several quantitative trait loci (QTLs) in this pathway. We performed a genome-wide survey on a set of chromosome segment substitution lines (CSSLs) which carried chromosomal segments from the heat resistant indica 9311 in the heat-sensitive japonica Nipponbare background. Four QTLs, qHAC4, qHAC8a, qHAC8b and qHAC10, which can reduce the deleterious effects of amylose content at high temperature, were identified and mapped to chromosome 4, 8, 8 and 10, respectively. The major QTL qHAC8a, with the highest LOD score of 6.196, was physically mapped to a small chromosome segment (~300 kb). The CSSLs carrying the qHAC8a, qHAC8b and/or qHAC4 from 9311 have the high pre-mRNA splicing efficiency of Wx gene and likely lead to stable amylose content at high temperature. Thus, increasing pre-mRNA processing efficiency of Wx gene could be an important regulation mechanism for maintaining stable amylose content in rice seeds at high temperature. In addition, our results provide a theoretical basis for breeding heat-stable grain in rice. 相似文献15.
Tao Wang Frank Fuxiang Mao Wenyu Lai Weiqiang Li Weihua Yu Zifei Wang Lirong Zhang Jinli Zhang Jin Niu Xiuming Zhang Bruce T Lahn Andy Peng Xiang 《BMC cell biology》2010,11(1):1-6
Background
Embryonic stem (ES) cells have attracted significant attention from researchers around the world because of their ability to undergo indefinite self-renewal and produce derivatives from the three cell lineages, which has enormous value in research and clinical applications. Until now, many ES cell lines of different mammals have been established and studied. In addition, recently, AS-ES1 cells derived from Apodemus sylvaticus were established and identified by our laboratory as a new mammalian ES cell line. Hence further research, in the application of AS-ES1 cells, is warranted.Results
Herein we report the generation of multiple mesodermal AS-ES1 lineages via embryoid body (EB) formation by the hanging drop method and the addition of particular reagents and factors for induction at the stage of EB attachment. The AS-ES1 cells generated separately in vitro included: adipocytes, osteoblasts, chondrocytes and cardiomyocytes. Histochemical staining, immunofluorescent staining and RT-PCR were carried out to confirm the formation of multiple mesodermal lineage cells.Conclusions
The appropriate reagents and culture milieu used in mesodermal differentiation of mouse ES cells also guide the differentiation of in vitro AS-ES1 cells into distinct mesoderm-derived cells. This study provides a better understanding of the characteristics of AS-ES1 cells, a new species ES cell line and promotes the use of Apodemus ES cells as a complement to mouse ES cells in future studies. 相似文献16.
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V. S. Bogdanova O. E. Kosterin A. K. Yadrikhinskiy 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(5):1163-1172
Key message
Divergent wild and endemic peas differ in hybrid sterility in reciprocal crosses with cultivated pea depending on alleles of a nuclear ‘speciation gene’ involved in nuclear–cytoplasmic compatibility.Background
In hybrids between cultivated and wild peas, nuclear–cytoplasmic conflict frequently occurs. One of the nuclear genes involved, Scs1, was earlier mapped on Linkage Group III.Results
In reciprocal crosses of seven divergent pea accessions with cultivated P. sativum, some alleles of Scs1 manifested incompatibility with an alien cytoplasm as a decrease in pollen fertility to about 50 % in the heterozygotes and lack of some genotypic classes among F2 segregants. Earlier, we defined monophyletic evolutionary lineages A, B, C and D of pea according to allelic state of three markers, from nuclear, plastid and mitochondrial genomes. All tested representatives of wild peas from the lineages A and C exhibited incompatibility due to Scs1 deleterious effects in crosses with testerlines of P. sativum subsp. sativum (the common cultivated pea) at least in one direction. A wild pea from the lineage B and a cultivated pea from the lineage D were compatible with the testerline in both directions. The tested accession of cultivated P. abyssinicum (lineage A) was partially compatible in both directions. The Scs1 alleles of some pea accessions even originating from the same geographic area were remarkably different in their compatibility with cultivated Pisum sativum cytoplasm.Conclusion
Variability of a gene involved in reproductive isolation is of important evolutionary role and nominate Scs1 as a speciation gene. 相似文献19.
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