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41.
Nicole Benhamou Pierre J. Lafontaine Dominique Mazau Marie-Thérèse Esquerré-Tugayé 《Planta》1991,184(4):457-467
An antiserum raised against deglycosylated hydroxyproline-rich glycoproteins (HPGPs) from melon (Cucumis melo L.) was used to study the relationship between Rhizobium infection and induction of HRGPs in bean (Phaseolus vulgaris L.) root nodule cells infected with either the wild-type or a C4-dicarboxylic acid mutant strain of Rhizobium leguminosarum bv. phaseoli. In effective nodules, where fixation of atmospheric dinitrogen is taking place, HRGPs were found to accumulate mainly in the walls of infected cells and in peribacteroid membranes surrounding groups of bacteroids. Internal ramifications of the peribacteroid membrane were also enriched in HRGPs whereas the peribacteroid space as well as the bacteroids themselves were free of these glycoproteins. In mutant-induced root nodules, HRGPs were specifically associated with the electron-dense, laminated structures formed in plastids as a reaction to infection by this mutant. The presence of HRGPs was also detected in the host cytoplasm. The aberrant distribution of HRGPs in infected cells of mutant-induced nodules likely reflects one aspect of the altered host metabolism in relation to peribacteroid-membrane breakdown. The possibility that the antiserum used for HRGP localization may have cross-reacted with ENOD 2 gene products is discussed in relation to amino-acid sequences and sites of accumulation. 相似文献
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45.
Jean-Franois Nav Dominique Wolff-Kugel Serge Halazy 《Bioorganic & medicinal chemistry letters》1992,2(12):1483-1488
Several carbocyclic phosphonate analogs of 2′,3′-dideoxyadenosine-5′-monophosphate (ddAMP) were pyrophosphorylated by E. coli 5-phosphoribosyl-1-pyrophosphate (PRPP) synthetase in the presence of PRPP. Structure-activity relationships are discussed. 相似文献
46.
Michel Goldberg Jacqueline Feinberg Sylvie Lecolle Marcia A. Kaetzel Dominique Rainteau James L. Lessard John R. Dedman Serge Weinman 《Cell and tissue research》1991,263(1):81-89
Summary Annexin VI and actin were detected by immunoblot analysis in the enamel- and dentin-related portions of dental tissues. Annexin VI was found mainly in the particulate fraction whereas actin was detected in both the soluble and particulate fractions. By immunoelectron microscopy, annexin VI antibodies conjugated with colloidal gold were seen to label the mitochondria, the cytosol and the nucleus of secretory ameloblasts and odontoblasts of rat incisor. In the processes of these cell, the plasmalemmal undercoat was labeled. Antiactin antibodies labeled the desmosome-like junctions, the cytosol, and the mitochondria of the cell bodies. Extensive labeling was seen at the periphery of the Tomes' processes and odontoblast processes. These results suggest that annexin VI may play a role in Ca2+-regulation in the cell bodies, especially as a calcium receptor protein in the mitochondria. Moreover, annexin VI and actin seem to be co-distributed in secretory processes. Thus, these proteins might be both involved in exocytotic and endocytotic events. 相似文献
47.
N. Aste C. Viglietti-Panzica A. Fasolo C. Andreone H. Vaudry G. Pelletier G. C. Panzica 《Cell and tissue research》1991,265(2):219-230
Summary In the present study, we have demonstrated, by means of the biotin-avidin method, the widespread distribution of neuropeptide Y (NPY)-immunoreactive structures throughout the whole brain of the Japanese quail (Coturnix coturnix japonica). The prosencephalic region contained the highest concentration of both NPY-containing fibres and perikarya. Immunoreactive fibres were observed throughout, particularly within the paraolfactory lobe, the lateral septum, the nucleus taeniae, the preoptic area, the periventricular hypothalamic regions, the tuberal complex, and the ventrolateral thalamus. NPY-immunoreactive cells were represented by: a) small scattered perikarya in the telencephalic portion (i.e. archistriatal, neostriatal and hyperstriatal regions, hippocampus, piriform cortex); b) medium-sized cell bodies located around the nucleus rotundus, ventrolateral, and lateral anterior thalamic nuclei; c) small clustered cells within the periventricular and medial preoptic nuclei. The brainstem showed a less diffuse innervation, although a dense network of immunopositive fibres was observed within the optic tectum, the periaqueductal region, and the Edinger-Westphal, linearis caudalis and raphes nuclei. Two populations of large NPY-containing perikarya were detected: one located in the isthmic region, the other at the boundaries of the pons with the medulla. The wide distribution of NPY-immunoreactive structures within regions that have been demonstrated to play a role in the control of vegetative, endocrine and sensory activities suggests that, in birds, this neuropeptide is involved in the regulation of several aspects of cerebral functions.Abbreviations
AA
archistriatum anterius
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AC
nucleus accumbens
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AM
nucleus anterior medialis
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APP
avian pancreatic polypeptide
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CNS
centrai nervous system
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CO
chiasma opticum
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CP
commissura posterior
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CPi
cortex piriformis
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DIC
differential interferential contrast
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DLAl
nucleus dorsolateralis anterior thalami, pars lateralis
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DLAm
nucleus dorsolateralis anterior thalami, pars medialis
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E
ectostriatum
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EW
nucleus of Edinger-Westphal
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FLM
fasciculus longitudinalis medialis
-
GCt
substantia grisea centralis
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GLv
nucleus geniculatus lateralis, pars ventralis
-
HA
hyperstriatum accessorium
-
Hp
hippocampus
-
HPLC
high performance liquid chromatography
-
HV
hyperstriatum ventrale
-
IF
nucleus infundibularis
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IO
nucleus isthmo-opticus
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IP
nucleus interpeduncularis
-
IR
immunoreactive
-
LA
nucleus lateralis anterior thalami
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LC
nucleus linearis caudalis
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LFS
lamina frontalis superior
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LH
lamina hyperstriatica
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LHRH
luteinizing hormone-releasing hormone
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LoC
locus coeruleus
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LPO
lobus paraolfactorius
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ME
eminentia mediana
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N
neostriatum
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NC
neostriatum caudale
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NPY
neuropeptide Y
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NIII
nervus oculomotorius
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NV
nervus trigeminus
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NVI
nervus facialis
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NVIIIc
nervus octavus, pars cochlearis
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nIV
nucleus nervi oculomotorii
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nIX
nucleus nervi glossopharyngei
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nBOR
nucleus opticus basalis (ectomamilaris)
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nCPa
nucleus commissurae pallii
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nST
nucleus striae terminalis
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OM
tractus occipitomesencephalicus
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OS
nucleus olivaris superior
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PA
palaeostriatum augmentatum
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PBS
phosphate-buffered saline
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POA
nucleus praeopticus anterior
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POM
nucleus praeopticus medialis
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POP
nucleus praeopticus periventricularis
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PP
pancreatic polypeptide
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PYY
polypeptide YY
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PVN
nucleus paraventricularis magnocellularis
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PVO
organum paraventriculare
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R
nucleus raphes
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ROT
nucleus rotundus
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RP
nucleus reticularis pontis caudalis
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Rpc
nucleus reticularis parvocellularis
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RPgc
nucleus reticularis pontis caudalis, pars gigantocellularis
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RPO
nucleus reticularis pontis oralis
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SCd
nucleus subcoeruleus dorsalis
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SCv
nucleus subcoeruleus ventralis
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SCNm
nucleus suprachiasmaticus, pars medialis
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SCNl
nucleus suprachiasmaticus, pars lateralis
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SL
nucleus septalis lateralis
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SM
nucleus septalis medialis
-
Ta
nucleus tangentialis
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TeO
tectum opticum
-
Tn
nucleus taeniae
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TPc
nucleus tegmenti pedunculo-pontinus, pars compacta
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TSM
tractus septo-mesencephalicus
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TV
nueleus tegmenti ventralis
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VeL
nucleus vestibularis lateralis
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VLT
nucleus ventrolateralis thalami
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VMN
nucleus ventromedialis hypothalami
A preliminary report of this study was presented at the 15th Conference of European Comparative Endocrinologists, Leuven, Belgium, September 1990 相似文献
48.
Monique Berthelon Catherine Caillaud Françoise Rey Philippe Labrune Dominique Melle Josué Feingold Jean Frézal Marie-Louise Briard Jean-Pierre Farriaux Pierre Guibaud Hubert Journel Bernard Le Marec Nicole Maurin Jean-Louis Nivelon Henri Plauchu Jean-Marie Saudubray Philippe Tron Jean Rey Arnold Münnich Stanislas Lyonnet 《Human genetics》1991,86(4):355-358
Summary A total of 252 chromosomes from 126 patients with phenylalanine hydroxylase (PAH) deficiencies were analyzed for both mutant genotypes and restriction fragment length polymorphism (RFLP) haplotypes at the PAH locus. The mutant genes studied originated either from Western Europe (116 alleles) or from Mediterranean countries (136 alleles). Only 27% of all mutant alleles were found to carry identified mutations, particularly mutations at codon 252 (2.3%), 261 (7.5%), 280 (6.3%), 408 (3.5%) and at the splice donor site of intron 12 (6.3%). The mutant genotypes were associated with RFLP haplotypes 7, 1, 38, 2 and 3 at the PAH locus respectively. Except for the splice mutation of intron 12, these associations were preferential, but not exclusive, since the other four mutations were found on the background of at least two RFLP haplotypes. These results, together with the observation that 85% of PAH deficient patients are heterozygotes for their mutant genotypes, emphasize the great heterogeneity of PAH deficiencies in Mediterranean countries and hamper systematic DNA testing for carrier status in this population. 相似文献
49.
Long-term cultures of certain rat and mouse cell lines carry several dicentric and some multicentric chromosomes. Using antikinetochore antibodies obtainable from serum of scleroderma (var. CREST) patients we studied the number of kinetochores formed along the length of these chromosomes. The rat cells displayed as many kinetochores as there were centromeres. However, mouse cells showed the synthesis of only one kinetochore in dicentric and multicentric chromosomes which had been in the culture for a period of 1 year or more. When translocations were induced by bleomycin in mouse L cells, the newly formed dicentric chromosomes showed the formation of two kinetochores. It is not known when the accessory centromeres lose their capacity to assemble kinetochore proteins. Possibly, in the rat the latent kinetochores lack a specific component which renders them ineffective for microtubule binding. The reason for the formation of only one kinetochore in mouse multicentric chromosomes is not clear. It may be due to the accumulation of mutations, modification of the kinetochore protein so that it lacks the antibody binding component, or a more effective regulatory gene than in the rat. 相似文献
50.
The chromosomal distribution of P and I transposable elements was studied, by in situ hybridisation, in 25 isofemale lines of Drosophila melanogaster collected at Nasr'Allah in Tunisia. An important interline variability for the number of copies of both elements was revealed. The mean number of copies per line was 31.3 for P and 21.0 for I. Certain chromosome arms had a higher frequency of copies than others: arm 3R had the highest frequency of I elements; the X chromosome had the highest frequency of P elements and the lowest frequency of I elements. For both P and I elements the number of copies on the different chromosome arms is independent. Furthermore, there is no significant correlation between the number of copies of P and the number of copies of I for a given line. A study of the localisation of hybridisation sites on the X chromosome revealed the existence of preferred regions for each family. The population studied was of type M' in the P-M system of hybrid dysgenesis. There is no direct relationship between the M potential of an isofemale line and its number of copies of P elements. These results are compared with those of other investigators and the consequences for cytotype determination are discussed. 相似文献