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111.
Molecular cloning of the mouse CCK gene: expression in different brain regions and during cortical development. 总被引:3,自引:1,他引:2
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In this paper we describe experiments that address specific issues concerning the regulation of the mouse cholecystokinin gene in brain and intestine. The mouse cholecystokinin gene was cloned and sequenced. Extensive homology among the mouse, man and rat genes was noted particularly in the three exons and the regions upstream of the RNA start site. RNAse protection assays for each of the three exons were used to demonstrate that CCK is expressed in only a subset of tissues and that the same cap site and splice choices are used in brain, intestine as well as in cerebellum, cortex, midbrain, hypothalamus and hippocampus. CCK RNA was also noted to be detectable in kidney. Thus the same gene using the same promoter is expressed in subsets of cells that differ in their biochemical, morphologic and functional characteristics. The level of expression of CCK was also monitored during mouse cortical development and the appearance of CCK RNA was compared to glutamate decarboxylase (GAD), enkephalin and somatostatin. It was noted that each of these cortical markers was first expressed at different times during cortical development. The appearance of CCK RNA during intestinal development was also measured and found to precede appearance in cortex by several days. 相似文献
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Fourteen native strains of Trichoderma spp. from wildand agricultural pathosystems in the state of Yucatan, Mexico, with growth-promoting ability of Capsicum chinense Jacq. seedlings were evaluated and antagonistic effect of their filtrate against second-stage juveniles (J2) of Meloidogyne incognita. The strains Th05-02 and Th27-08 showed the best significant effects on plant hight variable increments 55.57 and 47.62%, theTh07-04 with 29.48% more root length, theTh02-01 and Th07-04 isolates increased from 48.71 to 84.61% in volume radical and 53.40% of total dry biomass. Statistical analysis (p≤0.001) of Th43 and Th43-13-14 filtrates caused 100% mortality at 24 and 48h. In the test of reversibility to 24 h after replacing the filtrates Th43-13, Th43-14, TH09-06 and TH20-07 by sterile distilled water, the J2 did not recover their viability, so they were considered as the best potential strains of Trichoderma spp. with antagonistic capacity in J2 of M.incognita. 相似文献
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Nilton Lincopan Mariana RA Santana Eliana Faquim-Mauro Maria Helena B da Costa Ana M Carmona-Ribeiro 《BMC biotechnology》2009,9(1):5-19
Background
Silica particles cationized by dioctadecyldimethylammonium bromide (DODAB) bilayer were previously described. This work shows the efficiency of these particulates for antigen adsorption and presentation to the immune system and proves the concept that silica-based cationic bilayers exhibit better performance than alum regarding colloid stability and cellular immune responses for vaccine design. 相似文献118.
目的:建立丙型肝炎病毒NS3/4A丝氨酸蛋白酶体内活性评价模型。方法:利用NS4A/B是NS3/4A丝氨酸蛋白酶作用底物的特性,构建融合基因NS3/NS4A/B-SEAP,底物片段NS4A/B插在NS3/4A和人分泌性碱性磷酸酶(SEAP)之间,融合基因表达后SEAP的分泌依赖于有活性的NS3/4A在NS4A/B位点的切割。将含融合基因的质粒NS3/4A(△4AB)SEAP通过水动力转染技术转染到小鼠体内,检测小鼠血清中SEAP的活性,高活性的SEAP是该评价体系成立的证据。结果与结论:在瞬时表达NS3/4A的小鼠血清中检测到了高活性的SEAP,建立了可用于评价抗NS3/4A的小鼠体内瞬时模型。 相似文献
119.
Camarodont sea urchins possess a rapidly evolving actin gene family whose
members are expressed in distinct cell lineages in a developmentally
regulated fashion. Evolutionary changes in the actin gene family of
echinoids include alterations in number of family members, site of
expression, and gene linkage, and a dichotomy between rapidly and slowly
evolving isoform-specific 3' untranslated regions. We present sequence
comparisons and an analysis of the actin gene family in two congeneric sea
urchins that develop in radically different modes, Heliocidaris
erythrogramma and H. tuberculata. The sequences of several actin genes from
the related species Lytechinus variegatus are also presented. We compare
the features of the Heliocidaris and Lytechinus actin genes to those of the
the actin gene families of other closely related sea urchins and discuss
the nature of the evolutionary changes among sea urchin actins and their
relationship to developmental mode.
相似文献
120.
The phytochrome gene family in grasses (Poaceae): a phylogeny and evidence that grasses have a subset of the loci found in dicot angiosperms 总被引:13,自引:2,他引:11
The phytochrome nuclear gene family encodes photoreceptor proteins that
mediate developmental responses to red and far red light throughout the
life of the plant. From studies of the dicot flowering plant Arabidopsis,
the family has been modeled as comprising five loci, PHYA- PHYE. However,
it has been shown recently that the Arabidopsis model may not completely
represent some flowering plant groups because additional PHY loci related
to PHYA and PHYB of Arabidopsis apparently have evolved independently
several times in dicots, and monocot flowering plants may lack orthologs of
PHYD and PHYE of Arabidopsis. Nonetheless, the phytochrome nucleotide data
were informative in a study of organismal evolution because the loci occur
as single copy sequences and appear to be evolving independently. We have
continued our investigation of the phytochrome gene family in flowering
plants by sampling extensively in the grass family. The phytochrome nuclear
DNA data were cladistically analyzed to address the following questions:
(1) Are the data consistent with a pattern of differential distribution of
phytochrome genes among monocots and higher dicots, with homologs of PHYA,
B, C, D, and E present in higher dicots, but of just PHYA, B, and C in
monocots, and (2) what phylogenetic pattern within Poaceae do they reveal?
Results of these analyses, and of Southern blot experiments, are consistent
with the observation that the phytochrome gene family in grasses comprises
the same subset of loci detected in other monocots. Furthermore, for
studies of organismal phylogeny in the grass family, the data are shown to
provide significant support for relationships that are just weakly resolved
by other data sets.
相似文献