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1.
G-protein-coupled receptors (GPCRs) play a crucial role in mediating effects of extracellular messengers in a wide variety of biological systems, comprising the largest gene superfamily at least in mammals. Mammalian GPCRs are broadly classified into three families based on pharmacological properties and sequence similarities. These sequence similarities are largely confined to the seven transmembrane domains, and much less in the extracellular and intracellular loops and terminals (LTs). Together with the fact that the LTs vary considerably in length and sequence, the LT length of GPCRs has not been studied systematically. Here we have applied a statistical analysis to the length of the LTs of a wide variety of mammalian GPCRs in order to examine the existence of any trends in molecular architecture among a known mammalian GPCR population. Tree diagrams constructed by cluster analyses, using eight length factors in a given GPCR, revealed possible length relations among GPCRs and defined at least three groups. Most samples in Group J (joined) and Group M (minor) had an exceptionally long N-terminal and I3 loop, respectively; and other samples were considered as Group O (other/original). This length-based classification largely coincided with the conventional sequence- and pharmacology-based classification, suggesting that the LT length contains some biological information when analysed at the population level. Principle component analyses suggested the existence of inherent length differences between loops and terminals as well as between extracellular and intracellular LTs. Wilcoxon rank transformation tests unveiled statistically significant differences between Group O and Group J, not only in the N-terminal and I3 loop, but also in the E3 loop. Correlation analyses identified an E1-I2 length-correlation in Group O and Group J and an N-E3 length-correlation in Group J. Taken together, these results suggest a possible functional importance of LT length in the GPCR superfamily.  相似文献   
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Demersal fish resources in the East China and Yellow Seas were reviewed. A current and historical survey of the fishery was made. The distribution and migration of demersal fish were characterized, and an assessment of fishery resources was provided. The standardization of fishing efforts and resources management were also examined.  相似文献   
5.
The butterfly wing color patterns are unique to a species but are modified in response to cold-shock and tungstate treatments at the pupal stage, producing characteristic temperature–shock (TS) phenotypes that are distinct from the color patterns of seasonal polyphenism. In this study, we examined the efficiency of cold-shock and tungstate treatments for color pattern modifications at the pupal stage in relation to larval rearing conditions for the fall or summer morph using the blue pansy butterfly Junonia orithya. We found that larvae reared under the low-temperature condition that induces the fall morph exhibited hardiness against the color pattern changes imposed by cold-shock or tungstate treatment at the pupal stage. When larvae were fed an artificial diet containing tungstate under the high-temperature condition that induces the summer morph, they were still vulnerable to color pattern changes imposed by cold-shock or tungstate treatment at the pupal stage. Furthermore, larvae reared under the high-temperature condition were subjected to cold-shock or tungstate treatments at the pupal stage. In addition to the expected TS-type changes, these individuals exhibited a reduced number of eyespots in adults, which is a feature of the fall morph. These results suggest that the temperature condition experienced by the larvae, but not their consumption of tungstate, determines the sensitivity of the wing imaginal discs to cold-shock and tungstate treatments at the pupal stage.  相似文献   
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The Cape Gannet Morus capensis is one of several seabird species endemic to the Benguela upwelling ecosystem (BUS) but whose population has recently decreased, leading to an unfavourable IUCN Red List assessment. Application of ‘JARA’ (‘Just Another Red-List Assessment,’ a Bayesian state-space tool used for IUCN Red List assessments) to updated information on the areas occupied by Cape Gannets and the nest densities of breeding birds at their six colonies, suggested that the species should be classified as Vulnerable. However, the rate of decrease of Cape Gannets in their most-recent generation exceeded that of the previous generation, primarily as a result of large decreases at Bird Island, Lambert’s Bay, and Malgas Island, off South Africa’s west coast (the western part of their range). Since the 1960s, there has been an ongoing redistribution of the species from northwest to southeast around southern Africa, and ~70% of the population now occurs on the south coast of South Africa, at Bird Island in Algoa Bay, on the eastern border of the BUS. Recruitment rather than adult survival may be limiting the present population; however, information on the seabird’s demographic parameters and mortality in fisheries is lacking for colonies in the northern part of the BUS. Presently, major threats to Cape Gannet include: substantially decreased availability of their preferred prey in the west; heavy mortalities of eggs, chicks and fledglings at and around colonies, inflicted by Cape Fur Seals Arctocephalus pusillus and other seabirds; substantial disturbance at colonies caused by Cape Fur Seals attacking adult gannets ashore; oiling; and disease.  相似文献   
8.
We used recombinant adenoviruses as a means of expressing exogenous genes in olfactory neurons in vivo. A replication incompetent adenovirus (type 5, Ad5) carrying the reporter gene lacZ, which codes for the enzyme β-galactosidase (β-Gal), was applied in solution to the olfactory epithelia of rats. The expression of lacZ was controlled by the cytomegalovirus immediate-early promoter/enhancer. β-Gal expression was observed 1 day postinfection and was maximal at 3–10 days, although it could be detected for at least 21 days postinfection. Expression patterns were heterogeneous, ranging from a few percent to over 25% of the cells in different regions of both turbinate and septal epithelium. Staining was stronger in the olfactory versus respiratory epithelia. In olfactory epithelium staining was almost entirely restricted to olfactory neurons. β-Gal staining was also observed in the olfactory axons so that nerve bundles could be traced to their targets in the glomerular layer of the olfactory bulb. Intense staining of some glomeruli was evident as long as 21 days postinfection. There was no evidence of cell loss or tissue damage due to viral infection. These results demonstrate that it is possible to use recombinant Ad5 for expressing foreign genes in olfactory neurons. This technique could be used in olfactory neurons to increase expression levels of olfactory specific genes, including the odor receptor, putative guidance and growth molecules, or elements of the transduction cascade, in order to elucidate their biological functions in vivo. © 1996 John Wiley & Sons, Inc.  相似文献   
9.
The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected.  相似文献   
10.

Background:

Vascular growth is a prerequisite for adipose tissue (AT) development and expansion. Some AT cytokines and hormones have effects on vascular development, like vascular endothelial growth factor (VEGF‐A), angiopoietin (ANG‐1), ANG‐2 and angiopoietin‐like protein‐4 (ANGPTL‐4).

Methods:

In this study, the independent and combined effects of diet‐induced weight loss and exercise on AT gene expression and proteins levels of those angiogenic factors were investigated. Seventy‐nine obese males and females were randomized to: 1. Exercise‐only (EXO; 12‐weeks exercise without diet‐restriction), 2. Hypocaloric diet (DIO; 8‐weeks very low energy diet (VLED) + 4‐weeks weight maintenance diet) and 3. Hypocaloric diet and exercise (DEX; 8‐weeks VLED + 4‐weeks weight maintenance diet combined with exercise throughout the 12 weeks). Blood samples and fat biopsies were taken before and after the intervention.

Results:

Weight loss was 3.5 kg in the EXO group and 12.3 kg in the DIO and DEX groups. VEGF‐A protein was non‐significantly reduced in the weight loss groups. ANG‐1 protein levels were significantly reduced 22‐25% after all three interventions (P < 0.01). The ANG‐1/ANG‐2 ratio was also decreased in all three groups (P < 0.05) by 27‐38%. ANGPTL‐4 was increased in the EXO group (15%, P < 0.05) and 9% (P < 0.05) in the DIO group. VEGF‐A, ANG‐1, and ANGPTL‐4 were all expressed in human AT, but only ANGPTL‐4 was influenced by the interventions.

Conclusions:

Our data show that serum VEGF‐A, ANG‐1, ANG‐2, and ANGPTL‐4 levels are influenced by weight changes, indicating the involvement of these factors in the obese state. Moreover, it was found that weight loss generally was associated with a reduced angiogenic activity in the circulation.  相似文献   
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