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Mosiołek M Pasierbek P Malarz J Moś M Joachimiak AJ 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2005,43(3):161-167
Condensed Y chromosomes in Rumex acetosa L. root-tip nuclei were studied using 5-azaC treatment and immunohistochemical detection of methylated histones. Although Y chromosomes were decondensed within root meristem in vivo, they became condensed and heteropycnotic in roots cultured in vitro. 5-azacytidine (5-azaC) treatment of cultured roots caused transitional dispersion of their Y chromosome bodies, but 7 days after removal of the drug from the culture medium, Y heterochromatin recondensed and again became visible. The response of Rumex sex chromatin to 5-azaC was compared with that of condensed segments of pericentromeric heterochromatin in Rhoeo spathacea (Sw.) Steam roots. It was shown that Rhoeo chromocentres, composed of AT-rich constitutive heterochromatin, did not undergo decondensation after 5-azaC treatment. The Y-bodies observed within male nuclei of R. acetosa were globally enriched with H3 histone, demethylated at lysine 4 and methylated at lysine 9. This is the first report of histone tail-modification in condensed sex chromatin in plants. Our results suggest that the interphase condensation of Y chromosomes in Rumex is facultative rather than constitutive. Furthermore, the observed response of Y-bodies to 5-azaC may result indirectly from demethylation and the subsequent altered expression of unknown genes controlling tissue-specific Y-inactivation as opposed to the global demethylation of Y-chromosome DNA. 相似文献
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Starbäck P Wraith A Eriksson H Larhammar D 《Biochemical and biophysical research communications》2000,277(1):264-269
The neuropeptide Y family of G-protein-coupled receptors consists of five cloned members in mammals. Four genes give rise to functional receptors in all mammals investigated. The y6 gene is a pseudogene in human and pig and is absent in rat, but generates a functional receptor in rabbit and mouse and probably in the collared peccary (Pecari tajacu), a distant relative of the pig family. We report here that the guinea pig y6 gene has a highly distorted nucleotide sequence with multiple frame-shift mutations. One evolutionary scenario may suggest that y6 was inactivated before the divergence of the mammalian orders and subsequently resurrected in some lineages. However, the pseudogene mutations seem to be distinct in human, pig, and guinea pig, arguing for separate inactivation events. In either case, the y6 gene has a quite unusual evolutionary history with multiple independent deaths or resurrections. 相似文献
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Population genetics successfully applies surnames as quasi-genetic markers when estimating similarity between populations
and calculating the level of random inbreeding. These calculations are based on the isonymy coefficient, which assumes that
every surname is monophyletic, i.e., it originated from a single common ancestor and all namesakes are therefore relatives.
On the other hand, there is a general opinion that a typical Russian surname is polyphyletic: it originated multiple times
and most namesakes are, therefore, not related to each other. Combined studies of Y chromosomes and surnames now allow us
to address this issue. This study discusses approaches to statistical evaluation of Y chromosome haplogroup frequencies in
groups of people bearing the same surname (namesakes). The proposed index of accumulated haplogroup frequency eliminates the
artifactual effect of a randomly increased haplogroup frequency in namesakes by subtracting its population (expected) frequency
from the observed value, while the expected frequency is calculated as the weighted average of the frequencies of this haplogroup
in the populations where the surname carriers come from. From the total sample (comprising 1244 persons from 13 populations
of the historical Russian area), 123 individuals carrying 14 most frequent surnames were chosen. A comparison of the haplogroup
frequencies in these 14 namesake groups and in 14 respective population control groups compiled from the total sample showed
that accumulation of certain Y chromosome haplogroups was nonrandom even in carriers of widespread surnames. An analysis of
Y-STR haplotypes rather than Y-SNP haplogroups could provide a better insight into relationships between namesakes and will
be the subject of further research. 相似文献
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Population genetics successfully applies surnames as quasi-genetic markers when estimating similarity between populations and calculating a measure of random inbreeding. These calculations are based on an isonomy coefficient which assumes that every surname is monophyletic: that it originated from single common ancestor and all namesakes are therefore relatives. On the other hand, there is a general opinion that a typical Russian surname is polyphyletic: it originated multiple times and most namesakes are therefore not related to each other. Combined studies of Y chromosomes and surnames now allow us to address this issue. In this study, we discuss approaches for statistical evaluation of Y chromosomal haplogroup frequencies in groups of people bearing the same surname (namesakes). We propose an 'Index of Accumulated Haplogroup Frequency', which allows for errors due to random (artifactual) effects increasing a haplogroup frequency in a group of namesakes by subtracting the population frequency of this haplogroup. This population frequency is calculated as the weighted average of the frequencies of this haplogroup in the populations that the carriers of this surname come from. Fom the total sample (comprising 1244 persons from 13 populations of the historical Russian area) we chose 123 persons carrying 14 surnames which were the most frequent in the total sample. Haplogroup frequencies in these 14 "surname" groups were compared with the respective 14 "population" control groups compiled from the total sample as described above. We found that even these widespread surnames exhibit non-random accumulation of specific Y chromosomal haplogroups. More detailed analyses of the relationships between namesakes could be carried out using Y-STR haplotypes rather than Y-SNP haplogroups, and will be the subject of a future study. 相似文献
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神经肽Y(neuropeptide Y,NPY)是一种由36个氨基酸残基组成的肽类激素,属胰多肽家族,广泛分布于中枢及外周神经组织的神经元中。NPY主要参与摄食行为、心血管活动、垂体分泌等生理功能的调节。NPY还参与了痛觉调制。NPY受体有Y1、Y2、Y3、Y4、Y5和Y6六种亚型。目前对Y1受体和Y2受体的研究较多,显示Y1受体和Y2受体参与痛觉调制。但现在对NPY在痛觉中的具体作用机制还不清楚。该文对NPY及其Y1受体、Y2受体在痛觉调制中的作用作一概述。 相似文献
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《Journal of receptor and signal transduction research》2013,33(4):351-360
AbstractNeuropeptide Y (NPY) recognition by the human neuroblastoma cell lines SiMa, Kelly, SH‐SY5Y, CHP‐234, and MHH‐NB‐11 was analyzed in radioactive binding assays using tritiated NPY. For the cell lines CHP‐234 and MHH‐NB‐11 binding of [3H]propionyl‐NPY was observed with Kd‐values of 0.64 ± 0.07 nM and 0.53 ± 0.12 nM, respectively, determined by saturation analysis with non‐linear regression. The receptor subtype was determined by competition analysis using the subtype selective NPY analogues [Leu31, Pro34]‐NPY (NPY‐Y1, NPY‐Y5), [Ahx5‐24]‐NPY (NPY‐Y2), [Ala31, Aib32]‐NPY (NPY‐Y5), NPY [3‐36] (NPY‐Y2, NPY‐Y5), and NPY [13‐36] (NPY‐Y2). Both cell lines, CHP‐234 and MHH‐NB‐11, the latter one being characterized for NPY receptors for the first time, showed exclusive expression of NPY‐Y2 receptors. In both cell lines binding of NPY induced signal transduction, which was monitored as reduction of forskolin‐induced cAMP production in an ELISA. 相似文献
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目的:观察精子数目异常与小Y染色体及内分泌性腺激素水平。方法:对262名少精及无精症患者检测染色体,并对其中11例小Y染色体及随机抽取的15例Y染色体正常的患者运用磁性分离酶免疫测定法分别检测性腺激素。结果:小Y染色体检出率为4.19%(11/262),其内分泌性腺激素均呈高卵泡刺激素、高黄体生成素和低睾酮水平,与Y染色体正常的无精及少精症患者相比较,差异有显著性(P<0.05)。而小Y染色体不同精子数组各内分泌性腺激素比较,差异无显著性(P>0.05)。结论:精子数目异常可能与小Y染色体有关,小Y染色体基因改变可能是导致其内分泌性腺激素的变化因素。 相似文献
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目的:观察精子数目异常与小Y染色体及内分泌性腺激素水平。方法:对262名少精及无精症患者检测染色体,并对其中11例小Y染色体及随机抽取的15例Y染色体正常的患者运用磁性分离酶免疫测定法分别检测性腺激素。结果:小Y染色体检出率为4.19%(11/262),其内分泌性腺激素均呈高卵泡刺激素、高黄体生成素和低睾酮水平,与Y染色体正常的无精及少精症患者相比较.差异有显著性(P〈0.05)。而小Y染色体不同精子数组各内分泌性腺激素比较,差异无显著性(P〉0.05)。结论:精子数目畀常可能与小Y染色体有关,小Y染色体基因改变可能是导致其内分泌性腺激素的变化因素。 相似文献
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KLAUS SEUWEN MARIE-GABRIELLE LUDWIG ROMAIN M. WOLF 《Journal of receptor and signal transduction research》2013,33(5-6):599-610
The subfamily of G protein-coupled receptors comprising GPR4, OGR1, TDAG8, and G2A was originally characterized as a group of proteins mediating biological responses to the lipid messengers sphingosylphosphorylcholine (SPC), lysophosphatidylcholine (LPC), and psychosine. We challenged this view by reporting that OGR1 and GPR4 sense acidic pH and that this process is not affected by concentrations of SPC or LPC previously reported as agonistic. The original publications describing GPR4, OGR1, and G2A as receptors for LPC or SPC have now been retracted, and the first studies exploring receptors of this family as pH sensors in physiology have appeared. Here we review the status of this field and we confirm that GPR4, OGR1, and TDAG8 should be considered as proton-sensing receptors. Negative regulation of these receptors by high micromolar concentrations of lipids appears not specific in our experiments. 相似文献
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Seuwen K Ludwig MG Wolf RM 《Journal of receptor and signal transduction research》2006,26(5-6):599-610
The subfamily of G protein-coupled receptors comprising GPR4, OGR1, TDAG8, and G2A was originally characterized as a group of proteins mediating biological responses to the lipid messengers sphingosylphosphorylcholine (SPC), lysophosphatidylcholine (LPC), and psychosine. We challenged this view by reporting that OGR1 and GPR4 sense acidic pH and that this process is not affected by concentrations of SPC or LPC previously reported as agonistic. The original publications describing GPR4, OGR1, and G2A as receptors for LPC or SPC have now been retracted, and the first studies exploring receptors of this family as pH sensors in physiology have appeared. Here we review the status of this field and we confirm that GPR4, OGR1, and TDAG8 should be considered as proton-sensing receptors. Negative regulation of these receptors by high micromolar concentrations of lipids appears not specific in our experiments. 相似文献