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191.
Hernández CJ Ortíz T Rosa C Foster K Tyagi M Lugo N Albrecht R Chinapen S 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2007,146(4):477-481
Mucociliary activity is an important clearance mechanism in the respiratory system of air breathing vertebrates. Substance P (SP) and acetylcholine play a key role in the stimulation of the mucociliary transport in the frog palate. In this study, retrograde neuronal tracing was combined with immunocytochemistry for SP and choline acetyl transferase (ChAT) in the trigeminal ganglion and for neurokinin-1 receptor (NK1R) in the palate of Rana pipiens. The cells of origin of the palatine nerve were identified in the trigeminal ganglion using the retrograde tracer Fluorogold (FG). Optimal labeling of FG cells in the trigeminal ganglion was obtained at 96 h of exposure. Immunoflorescent shows that SP and acetylcholine are co-localized in 92% of the cells labeled with FG in the trigeminal ganglion. NK1 receptors were found in the membrane of epithelial and goblet cells of the palate. Ultrastructural study of the palate showed axonal-like endings with vesicles in connection with epithelial and goblet cells. These results further support the concerted action of both neurotransmitters in the regulation of mucociliary activity in the frog palate. 相似文献
192.
Ulrike Winter Nicolas Stankovic‐Valentin Petra Haas Kay Hofmann Henning Urlaub Huib Ovaa Joachim Wittbrodt Erik Meulmeester Frauke Melchior 《EMBO reports》2012,13(10):930-938
Isopeptidases are essential regulators of protein ubiquitination and sumoylation. However, only two families of SUMO isopeptidases are at present known. Here, we report an activity‐based search with the suicide inhibitor haemagglutinin (HA)‐SUMO‐vinylmethylester that led to the identification of a surprising new SUMO protease, ubiquitin‐specific protease‐like 1 (USPL1). Indeed, USPL1 neither binds nor cleaves ubiquitin, but is a potent SUMO isopeptidase both in vitro and in cells. C13orf22l—an essential but distant zebrafish homologue of USPL1—also acts on SUMO, indicating functional conservation. We have identified invariant USPL1 residues required for SUMO binding and cleavage. USPL1 is a low‐abundance protein that colocalizes with coilin in Cajal bodies. Its depletion does not affect global sumoylation, but causes striking coilin mislocalization and impairs cell proliferation, functions that are not dependent on USPL1 catalytic activity. Thus, USPL1 represents a third type of SUMO protease, with essential functions in Cajal body biology. 相似文献
193.
Summary Two sugarbeet (Beta vulgaris L.) genotypes, REL-1 and REL-2, were used to measure the level of somatic embryo and shoot production from hormone-autonomous
callus plated under varied nutrient medium combinations of abscisic acid with the growth regulators 6-benzyladenine, 1-naphthaleneacetic
acid, or 2,4-dichlorophenoxyacetic acid, with eight sole nitrogen sources, or with different sucrose concentrations. Clone
REL-2 produced embryos up to 35-fold more frequently than clone REL-1. Inclusion of abscisic acid at some concentrations consistently
improved embryo production in all experiments and was observed to stimulate shoot production. At some concentrations, 1-naphthaleneacetic
acid as well as urea and glutamine stimulated greater embryo production over the control, but only for REL-1, for which there
was greater room for improvement. Three and five percent sucrose were superior to 1, 7, and 9%. Higher initial 6-benzyladenine
concentration [in the range 0, 0.1−1.0 mg/L (0.44−4.44 μM)] was associated with lower embryo production but greater shoot regeneration for both clones. REL-2 was significantly better
than REL-1 in shoot regeneration. The range of embryo production was more than 35-fold between genotypes, whereas the range
of physiological effects was no greater than 10-fold. REL-2 has been released to sugarbeet researchers because of its superior
embryogenic and shoot regeneration abilities for application in biotechnology. 相似文献
194.
Bardet–Biedl Syndrome is a multisystem autosomal recessive disorder characterized by central obesity, polydactyly, hypogonadism, learning difficulties, rod-cone dystrophy and renal dysplasia. Bardet–Biedl Syndrome has a prevalence rate ranging from 1 in 100,000 to 1 in 160,000 births although there are communities where Bardet–Biedl Syndrome is found at a higher frequency due to consanguinity. We report here a Pakistani consanguineous family with two affected sons with typical clinical features of Bardet–Biedl Syndrome, in addition to abnormal liver functioning and bilateral basal ganglia calcification, the latter feature being typical of Fahr's disease. Homozygous regions obtained from SNP array depicted three known genes BBS10, BBS14 and BBS2. Bidirectional sequencing of all coding exons by traditional sequencing of all these three genes showed a homozygous deletion of 10 nucleotides (c.1958_1967del), in BBS10 in both affected brothers. The segregation analysis revealed that the parents, paternal grandfather, maternal grandmother and an unaffected sister were heterozygous for the deletion. Such a large deletion in BBS10 has not been reported previously in any population and is likely to be contributing to the phenotype of Bardet–Biedl Syndrome in this family. 相似文献
195.
EB病毒潜伏膜蛋白-1介导的信号传导 总被引:11,自引:0,他引:11
EB病毒编码LMP-1介导的信号传导途径已引起人们广泛的注意.它涉及TRAF/TRADD途径,AP-1途径,JAK/STAT及其他途径.就此作一综述,有助于人们认识LMP-1的致瘤效应. 相似文献
196.
Background and aims
Sustained interaction of advanced glycation end products (AGEs) with their receptor RAGE and subsequent signaling plays an important role in the development of diabetic complications. Genetic variation of RAGE gene may be associated with the development of vascular complications in type 2 diabetes mellitus (T2DM).Objectives
The present study aimed to explore the possible association of RAGE gene polymorphisms namely − 374T/A, − 429T/C and G82S with serum level of AGEs, paraoxonase (PON1) activity and macro-vascular complications (MVC) in Indian type 2 diabetes mellitus patients (T2DM).Methods
A total of 265 diabetic patients, including DM without any complications (n = 135), DM-MVC (n = 130) and 171 healthy individuals were enrolled. Genotyping of RAGE variants were assessed by polymerase chain reaction-restriction fragment length polymorphism. Serum AGEs were estimated by ELISA and fluorometrically. and PON1 activity was assessed spectrophotometrically.Results
Of the three examined SNPs, association of − 429T/C polymorphism with MVC in T2DM was observed (OR = 3.001, p = 0.001) in the dominant model. Allele ‘A’ of − 374T/A polymorphism seems to confer better cardiac outcome in T2DM. Patients carrying C allele (− 429T/C) and S allele (G82S) had significantly higher AGEs levels. − 429T/C polymorphism was also found to be associated with low PON1 activity. Interaction analysis revealed that the risk of development of MVC was higher in T2DM patients carrying both a CC genotype of − 429T/C polymorphism and a higher level of AGEs (OR = 1.343, p = 0.040).Conclusion
RAGE gene polymorphism has a significant effect on AGEs level and PON1 activity in diabetic subjects compared to healthy individuals. Diabetic patients with a CC genotype of − 429T/C are prone to develop MVC, more so if AGEs levels are high and PON1 activity is low. 相似文献197.
Marsano RM Milano R Minervini C Moschetti R Caggese C Barsanti P Caizzi R 《Genetica》2003,117(2-3):281-289
The molecular organization of the heterochromatic h39 region of the Drosophila melanogaster second chromosome has been investigated by studying two BAC clones identified both by Southern blotting and by FISH experiments as containing tandem arrays of Bari1, a transposable element present only in this region. Such BAC clones appear to contain different portions of the h39 region since they differ in the DNA sequences flanking the Bari1 repeats on both sides. Thus, the 80 Bari1 copies estimated to be present in the h39 region are split into at least two separated subregions. On the basis of the analysis of the flanking sequences a possible mechanism depending on an aberrant activity of the Bari1 transposase is proposed for the genesis of the heterochromatic tandem arrays of the element. 相似文献
198.
199.
* Actin organization and dynamics are essential for cell division, growth and cytoplasmic streaming. Here we analyse the effects of the overexpression of Actin Interacting Protein 1 (AIP1) on Arabidopsis development. * Arabidopsis plants were transformed with an ethanol-inducible AIP1 construct and the characteristics of these plants were analysed after induction. * When AIP1 was increased to approx. 90% above wild-type values, root hair development and actin organization in all cell types examined were disrupted. * Our data demonstrate that AIP1 is a key regulator of actin organization and that its regulation is essential for normal plant cell morphogenesis. 相似文献
200.