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排序方式: 共有451条查询结果,搜索用时 15 毫秒
61.
JA Nboyine S Boyer D Saville MJ Smith SD Wratten 《New Zealand journal of zoology.》2016,43(4):336-350
The endemic New Zealand ground wētā (Hemiandrus sp. ‘promontorius’) has a Naturally Uncommon conservation status. This is because of the paucity of information on its density and distribution. Here, the biology, density and distribution of a population of this wētā found in and around vineyards in the Awatere Valley, Marlborough was studied. Wētā density was assessed in vineyards, paddocks and shrublands in this valley. Soil moisture, penetration resistance, pH and organic matter were recorded at locations with and without wētā. Wētā density in vineyards was significantly higher than in either paddocks or shrub habitats. In vineyards, the density of this insect was significantly higher under-vines than in the inter-rows. Higher numbers of this wētā were found in moist soils that required lower force to burrow. Females laid an average of 55 eggs between March and April, which hatched in September. These findings highlight the intersection between agriculture and conservation. 相似文献
62.
Distinguishing morphologically cryptic taxa, by definition, requires genetic data such as DNA sequences. However, DNA sequences may not be obtained easily for taxa from remote sites. Here we provide the details of a high-resolution melt-curve-based method using taxon-specific primers that can distinguish two taxa of Adélie penguins, and that will be usable in Antarctica when combined with some of the newly developed field-deployable thermal cyclers. We suggest that the wider adoption of field-deployable polymerase-chain-reaction-based techniques will enable faster assignation of haplotype to individuals in situ, and so allow the targeting of observations and sample collection to specimens relevant to the research question. Targeting individuals will also reduce the need to repeatedly handle animals and reduce the time and travel required to complete field work. 相似文献
63.
Characterization of a caveolin‐1 mutation associated with both pulmonary arterial hypertension and congenital generalized lipodystrophy
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Bing Han Courtney A. Copeland Yumeko Kawano Erika Berman Rosenzweig Eric D. Austin Layla Shahmirzadi Sha Tang Krishnan Raghunathan Wendy K. Chung Anne K. Kenworthy 《Traffic (Copenhagen, Denmark)》2016,17(12):1297-1312
Congenital generalized lipodystrophy (CGL) and pulmonary arterial hypertension (PAH) have recently been associated with mutations in the caveolin‐1 ( CAV1 ) gene, which encodes the primary structural protein of caveolae. However, little is currently known about how these CAV1 mutations impact caveolae formation or contribute to the development of disease. Here, we identify a heterozygous F160X CAV1 mutation predicted to generate a C‐terminally truncated mutant protein in a patient with both PAH and CGL using whole exome sequencing, and characterize the properties of CAV1 , caveolae‐associated proteins and caveolae in skin fibroblasts isolated from the patient. We show that morphologically defined caveolae are present in patient fibroblasts and that they function in mechanoprotection. However, they exhibited several notable defects, including enhanced accessibility of the C‐terminus of wild‐type CAV1 in caveolae, reduced colocalization of cavin‐1 with CAV1 and decreased stability of both 8S and 70S oligomeric CAV1 complexes that are necessary for caveolae formation. These results were verified independently in reconstituted CAV1 ?/? mouse embryonic fibroblasts. These findings identify defects in caveolae that may serve as contributing factors to the development of PAH and CGL and broaden our knowledge of CAV1 mutations associated with human disease. 相似文献
64.
Chromosomal localization of three human genes encoding bone morphogenetic protein receptors 总被引:7,自引:0,他引:7
Anna-Karin Åström Donald Jin Takeshi Imamura Eva Röijer Bradley Rosenzweig Kohei Miyazono Peter ten Dijke Göran Stenman 《Mammalian genome》1999,10(3):299-302
Bone morphogenetic proteins (BMPs) are members of the TGF-β superfamily that play a pivotal role in bone formation during
embryogenesis and fracture repair. BMP signaling occurs via hetero-oligomeric serine/threonine kinase complexes of BMP type
I (BMPR-IA or BMPR-IB) and type II receptors (BMPR-II). BMPR-IA and IB are closely related receptors, with sequence differences
conserved between different species, suggesting that they serve distinct functions. Here we report the cDNA cloning of human
BMPR1B and the chromosomal localization of all three BMPR genes. Using somatic cell hybrid and FISH analyses, the BMPR1A,
BMPR1B, and BMPR2 genes were assigned to 10q23, 4q22-24, and 2q33-34, respectively. A processed BMPR1A pseudogene was mapped
to 6q23.
Received: 17 February 1997 / Accepted: 15 October 1998 相似文献
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The invasive freshwater snail Tarebia granifera (Lamarck, 1822) was first reported in South Africa in 1999 and it has become widespread across the country, with some evidence to suggest that it reduces benthic macroinvertebrate biodiversity. The current study aimed to identify the primary abiotic drivers behind abundance patterns of T. granifera, by comparing the current abundance of the snail in three different regions, and at three depths, of the highly modified Nseleni River in KwaZulu-Natal, South Africa. Tarebia granifera was well established throughout the Nseleni River system, with an overall preference for shallow waters and seasonal temporal patterns of abundance. Although it is uncertain what the ecological impacts of the snail in this system are, its high abundances suggest that it should be controlled where possible and prevented from invading other systems in the region. 相似文献
68.
Rosenzweig DH Nair KS Levay K Peshenko IV Crabb JW Dizhoor AM Slepak VZ 《The Biochemical journal》2009,417(3):803-812
Vertebrate phototransduction is mediated by cGMP, which is generated by retGC (retinal guanylate cyclase) and degraded by cGMP phosphodiesterase. Light stimulates cGMP hydrolysis via the G-protein transducin, which directly binds to and activates phosphodiesterase. Bright light also causes relocalization of transducin from the OS (outer segments) of the rod cells to the inner compartments. In the present study, we show experimental evidence for a previously unknown interaction between G(alphat) (the transducin alpha subunit) and retGC. G(alphat) co-immunoprecipitates with retGC from the retina or from co-transfected COS-7 cells. The retGC-G(alphat) complex is also present in cones. The interaction also occurs in mice lacking RGS9 (regulator of G-protein signalling 9), a protein previously shown to associate with both G(alphat) and retGC. The G(alphat)-retGC interaction is mediated primarily by the kinase homology domain of retGC, which binds GDP-bound G(alphat) stronger than the GTP[S] (GTPgammaS; guanosine 5'-[gamma-thio]triphosphate) form. Neither G(alphat) nor G(betagamma) affect retGC-mediated cGMP synthesis, regardless of the presence of GCAP (guanylate cyclase activating protein) and Ca2+. The rate of light-dependent transducin redistribution from the OS to the inner segments is markedly accelerated in the retGC-1-knockout mice, while the migration of transducin to the OS after the onset of darkness is delayed. Supplementation of permeabilized photoreceptors with cGMP does not affect transducin translocation. Taken together, these results suggest that the protein-protein interaction between G(alphat) and retGC represents a novel mechanism regulating light-dependent translocation of transducin in rod photoreceptors. 相似文献
69.
Arthur L. Kruckeberg Saisubramanian Nagarajan Frank Rosenzweig 《Analytical biochemistry》2009,391(2):160-162
We have developed a method for preparing high-quality total RNA from Ca-alginate-encapsulated Saccharomyces cerevisiae that is suitable for microarray analysis. Encapsulated cells were harvested from immobilized cell reactors and flash-frozen in liquid nitrogen. Following low-temperature mechanical disruption, cells were freed from Ca-alginate by reverse ionotropic gelation and purified by centrifugation, and then total RNA was extracted using hot acid phenol. The yield and quality of the RNA were consistently high; the RNA was free of contaminating alginate, and in microarray analysis it performed as well as RNA isolated from planktonic cells. 相似文献
70.
Ritha JA Njau Don de Savigny Lucy Gilson Eleuther Mwageni Franklin W Mosha 《Malaria journal》2009,8(1):1-27