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1.
β-Glucuronidase activity was measured in mouse embryos during the preimplantation period of development by using a microfluorometric assay. A 100-fold increase in activity was observed between 57 (8-cell stage) and 84 hr (morulae) of development. Activity changes between 30 and 60 hr were also significant. Genetic variants of β-glucuronidase occur between the strains of mice and which differ in levels of activity and heat denaturation kinetics. Activity changes and heat denaturation kinetics of β-glucuronidase in and F1 hybrid embryos were compared, and it was demonstrated that paternal genes were expressed during the 100-fold increase in activity and that embryonic genes may be functioning between 30 and 60 hr of development. 相似文献
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Lisbet Camper Karin Holmvall Christel Wängnerud Attila Aszódi Evy Lundgren-Åkerlund 《Cell and tissue research》2001,306(1):107-116
We have previously identified and characterised the collagen type II-binding integrin subunit alpha10, which is a member of the beta1 family and is expressed by chondrocytes. In the present study, we examined the expression of the alpha10 integrin in various mouse tissues. Immunohistochemical analysis of alpha10 on cryosections from 3-day-old mice demonstrated that alpha10beta1 was present in the hyaline cartilage of joints, vertebral column, trachea and bronchi. In addition, alpha10 was found in the ossification groove of Ranvier, in the aortic and atrioventricular valves of the heart and in the fibrous tissue lining skeletal muscle and ligaments. Overall, the distribution was distinct from that of the collagen-binding integrins alpha1beta1 and alpha2beta1. We also found that alpha10beta1was the dominating collagen-binding integrin during cartilage development. Expression of alpha10 appeared at embryonic day 11.5 (E11.5) at the same time as chondrogenesis started as judged by collagen type II expression. At E13.5, alpha10 was present throughout the anlage as well as in the perichondrium and in mesenchyme just outside the perichondrium, where it localised with collagen type I. Four weeks after birth, alpha10 was prominent both at the articular surface and in the growth plate. In conclusion, we found that integrin alpha10beta1 was a major collagen-binding integrin during cartilage development and in mature hyaline cartilage. In addition, we found that alpha10beta1 was present in some fibrous tissues. 相似文献
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Céline Heng Olivier Lefebvre Annick Klein Malia M Edwards Patricia Simon-Assmann Gertraud Orend Dominique Bagnard 《Cell Adhesion & Migration》2011,5(6):480-489
We had developed a conditional Laminin α1 knockout-mouse model (Lama1cko) bypassing embryonic lethality of Lama1 deficient mice to study the role of this crucial laminin chain during late developmental phases and organogenesis. Here, we report a strong defect in the organization of the adult cerebellum of Lama1cko mice. Our study of the postnatal cerebellum of Lama1cko animals revealed a disrupted basement membrane correlated with an unexpected excessive proliferation of granule cell precursors in the external granular layer (EGL). This was counteracted by a massive cell death occurring between the postnatal day 7 (P7) and day 20 (P20) resulting in a net balance of less cells and a smaller cerebellum. Our data show that the absence of Lama1 has an impact on the Bergmann glia scaffold that aberrantly develops. This phenotype is presumably responsible for the observed misplacing of granule cells that may explain the overall perturbation of the layering of the cerebellum and an aberrant folia formation.Key words: cerebellum, development, laminin, cell migration, laminin-111 相似文献
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《Cell Adhesion & Migration》2013,7(6):480-489
We had developed a conditional Laminin α 1 knockout-mouse model (Lama1cko) bypassing embryonic lethality of Lama1 deficient mice to study the role of this crucial laminin chain during late developmental phases and organogenesis. Here, we report a strong defect in the organization of the adult cerebellum of Lama1cko mice. Our study of the postnatal cerebellum of Lama1cko animals revealed a disrupted basement membrane correlated to an unexpected excessive proliferation of granule cell precursors in the external granular layer (EGL). This was counteracted by a massive cell death occurring between the postnatal day 7 (P7) and day 20 (P20) resulting in a net balance of less cells and a smaller cerebellum. Our data show that the absence of Lama1 has an impact on the Bergmann glia scaffold that aberrantly develops. This phenotype is presumably responsible for the observed misplacing of granule cells that may explain the overall perturbation of the layering of the cerebellum and an aberrant folia formation. 相似文献
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Partial structure of the human α2(IV) collagen chain and chromosomal localization of the gene (COL4A2) 总被引:3,自引:0,他引:3
Paul D. Killen Clair A. Francomano Yoshihiko Yamada William S. Modi Stephen J. O'Brien 《Human genetics》1987,77(4):318-324
Summary We have isolated a 2.1-kb cDNA clone from a human placental library encoding part of the 2 chain of collagen IV, a major structural protein of basement membranes. The DNA sequence encodes 446 amino acids in the triplehelical domain plus the 227 amino acids of the carboxy-terminal globular domain. The latter structure is composed of two homologous subdomains and is highly conserved between the 1 and 2 chains. The triple-helical domain contained seven interruptions of the Gly-X-Y repeat and these interruptions were in general larger than their counterparts in the 1 chain. DNA from human rodent hybrid cell lines was analyzed under conditions in which there was no cross-hybridization of the 2(IV) cDNA probe with the gene for the 1(IV) collagen chain. An Eco RI fragment characteristic of the 2 chain had a concordance of 0.97 with chromosome 13. This result was confirmed and extended with in situ localization of the gene at 13q34. Since the 1(IV) gene has previously been localized to 13q34, the two type IV collagen genes reside in the same chromosome region (13q34), possibly in a gene cluster. The presence of the genes for type IV collagen chains on chromosome 13 excludes a primary role for these genes in adult polycystic kidney disease and X-linked forms of hereditary nephritis. 相似文献
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Summary The mammalian pineal gland contains pinealocytes, interstitial glial cells, perivascular macrophages, neurons and neuron-like
cells. The neuronal identity of neurons and neuron-like cells was an enigma. α-Internexin and peripherin are specific neuronal
intermediate filament proteins and are expressed differentially in the CNS and PNS. We investigated the development of immunoreactivity
and expression patterns of mRNAs for α-internexin and peripherin in the mouse pineal gland to determine the neuronal identity
of these cells. Both α-internexin- and peripherin-immunoreactive cells were readily visualized only after birth. Both proteins
were at the highest level on the postnatal day 7 (P7), rapidly declined at P14, and obtained their adult level at P21. Both
protein and mRNA of α-internexin are expressed in some cells and nerve processes, but not all, of adult mouse pineal gland.
Less number of peripherin immunoreactive or RNA-expressing cells and nerve processes were identified. Accumulations of α-internexin
and peripherin proteins were also found in the cells from the aged pineal gland (P360). We concluded that some cells in the
developing mouse pineal gland may differentiated into neurons and neuron-like cells expressing both α-internexin and/or peripherin
only postnatally, and these cells possess dual properties of CNS and PNS neurons in nature. We suggested that they may act
as interneurons between the pinealocyte and the distal neurons innervating the pinealocytes, or form a local circuitry with
pinealocytes to play a role of paracrine regulatory function on the pinealocytes. 相似文献
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Glycosylation is one of the most important post-translational modifications and it is clear that the single step of -1,4-galactosylation is performed by a family of -1,4-galactosyltransferases (4-GalTs) and that each member of this family may play a distinct role in different tissues and cells. In this study, we characterized the gene expression of six 4-GalTs in mouse testis and analyzed the changes of galactosylation of testis glycoproteins during postnatal development. Northern blot analysis revealed that 4-GalT-I and 4-GalT-IV were expressed mainly in newborn mouse testis and that the expression of 4-GalT-II increased markedly and persisted at the highest levels in adult mouse testis. The expression of 4-GalT-III and 4-GalT-V, however, remained relatively at low levels during mouse testicular development. In contrast, the expression of 4-GalT-VI was undetectable in mouse testis. The gene expression of 4-GalT-II in mouse testis was further analyzed by in situ hybridization due to its unique expression pattern. Strong hybridization signals were detected in the seminiferous tubules and the expression varied among the different stages of spermatogenic differentiation. The distinct gene expression patterns of 4-GalTs in mouse testis could affect the differential galactosylation of testis glycoproteins, as revealed by lectin histochemistry analysis. 相似文献
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Although estrogen action is indispensable for normal bone growth in both genders, the roles of estrogen receptors (ERs) in
mediating bone growth are not fully understood. The effects of ER inactivation on bone growth are sex and age dependent, and
may differ between the axial and appendicular regions. In this study, the spatial and temporal expression of ERα and β in
the tibial and spinal growth plates of the female and male rats during postnatal development was examined to explore the possible
mechanisms. The level of mRNA was examined and compared with quantitative real-time PCR. The spatial location was determined
by immunohistochemical analysis. The 1-, 4-, 7-, 12- and 16-week age stages correspond to early life, puberty and early adulthood
after puberty, respectively. Gender- and region-specific differences in ERα and β expression were shown in the growth plates.
Mainly nuclear staining of ERα and β immunoreactivity was demonstrated in the spinal and tibial growth plate chondrocytes
for both genders. Moreover, our study indicated significant effect of gender on temporal ERα and β expression and of region
on temporal ERα/ERβ expression ratio. However, spatial differences of region-related ERα and β expression were not observed.
Gender-related spatial changes were detected only at 16 weeks of both spine and limb growth plates. ERα and β immunoreactivity
was detected in the resting, proliferative and prehypertrophic chondrocytes in the early life stage and during puberty. After
puberty, ERα expression was mainly located in the late proliferative and hypertrophic chondrocytes in female, whereas the
expression still extended from the resting to hypertrophic chondrocytes in males. Gender- and region-specific expression patterns
of ERα and β gene might be one possible reason for differences in sex- and region-related body growth phenotypes. Gender,
age and region differences should be taken into consideration when the roles of ERs in the growth plate are investigated. 相似文献
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The amino acid sequences of type I collagen containing α1(I) and α2 chains at a ratio of 2:1, and of type III collagen consisting of α1 (III) chains are known. A statistical analysis of the sequences of these α chains is presented. The inter-chain comparison showed a high level of homology between the three α chains. The interactive amino acids, such as the polar charged and part of the hydrophobic residues responsible for the assembly of the molecules, are strongly conserved. The intra-chain analysis revealed that the α chains are divided into four related D units, each with a length of 234 residues. Between the D units within a chain the polar residues show a higher variability than the hydrophobic amino acids.Besides the D units, other periodicities such as (78 residues), (39 residues), (21 residues) and (18 residues) were observed, particularly in α1 (I) and α1 (III). The D unit is a functional repeat that is formed by the interactive polar charged and hydrophobic residues and which determines the aggregation of the molecules. The unit is mainly pronounced by the non-interactive residues such as proline and alanine and appears to be a reminiscence of a primordial gene. The smaller periodic repeating units may be considered as additional genetic units or as structural units, which determine the triplehelical pitch and thus the lateral aggregation of the molecules.In contrast to α1 (I) and α1 (III), the α2 chain shows less regularity in its internal structure. 相似文献
16.
Klausdieter Bauer 《Human genetics》1973,17(3):267-270
Summary The cross-reactions of human 1-antichymotrypsin and C 1 q with their homologues in the plasmas of the chimpanzee, several Old World monkeys and nine non-primate eutheria were investigated by standard procedures. The results show that cross-reactions are limited to the first species mentioned. Comparative Ouchterlony tests and absorption controls revealed the presence of two (human) determinants on both human and chimpanzee molecules, while the cercopithecoids analyzed carried only one of them on their homologue. The results are discussed briefly with reference to earlier findings from this laboratory.
Zusammenfassung Die Kreuzreaktionen des menschlichen 1-Antichymotrypsin und des C 1 q mit seinen Homologen im Plasma des Schimpansen, einiger Altweltaffen und demjenigen von 9 Nichtprimaten (Eutheria) wurden mit Standardmethoden untersucht. Die Ergebnisse zeigen, daß Kreuzreaktionen auf die zuerst genannten Species beschränkt sind. Vergleichende Ouchterlony-Tests und Absorptionskontrollen ließen die Anwesenheit zweier (menschlicher) Determinaten auf den Molekülen des Menschen und des Schimpansen erkennbar werden, während die untersuchten Cercopithecoidea nur eine dieser Determinanten besitzen. Die Ergebnisse werden kurz im Zusammenhang mit früheren Befunden aus unserem Laboratorium diskutiert.相似文献
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Matthias Roediger Nicolai Miosge Nikolaus Gersdorff 《Journal of molecular histology》2010,41(2-3):177-184
Laminins are the major glycoproteins present in all basement membranes. Previously, we showed that perlecan is present during human development. Although an overview of mRNA-expression of the laminin β1 and β2 chains in various developing fetal organs is already available, a systematic localization of the laminin β1 and β2 chains on the protein level during embryonic and fetal human development is missing. Therefore, we studied the immunohistochemical expression and tissue distribution of the laminin β1 and β2 chains in various developing embryonic and fetal human organs between gestational weeks 8 and 12. The laminin β1 chain was ubiquitously expressed in the basement membrane zones of the brain, ganglia, blood vessels, liver, kidney, skin, pancreas, intestine, heart and skeletal system. Furthermore, the laminin β2 chain was present in the basement membrane zones of the brain, ganglia, skin, heart and skeletal system. The findings of this study support and expand upon the theory that these two laminin chains are important during human development. 相似文献
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