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31.
32.
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
33.
Biological soil crusts in ecological restoration: emerging research and perspectives 总被引:1,自引:0,他引:1
Anita Antoninka Akasha Faist Emilio Rodriguez‐Caballero Kristina E. Young V. Bala Chaudhary Lea A. Condon David A. Pyke 《Restoration Ecology》2020,28(Z2):S3-S8
Drylands encompass over 40% of terrestrial ecosystems and face significant anthropogenic degradation causing a loss of ecosystem integrity, services, and deterioration of social‐ecological systems. To combat this degradation, some dryland restoration efforts have focused on the use of biological soil crusts (biocrusts): complex communities of cyanobacteria, algae, lichens, bryophytes, and other organisms living in association with the top millimeters of soil. Biocrusts are common in many ecosystems and especially drylands. They perform a suite of ecosystem functions: stabilizing soil surfaces to prevent erosion, contributing carbon through photosynthesis, fixing nitrogen, and mediating the hydrological cycle in drylands. Biocrusts have emerged as a potential tool in restoration; developing methods to implement effective biocrust restoration has the potential to return many ecosystem functions and services. Although culture‐based approaches have allowed researchers to learn about the biology, physiology, and cultivation of biocrusts, transferring this knowledge to field implementation has been more challenging. A large amount of research has amassed to improve our understanding of biocrust restoration, leaving us at an opportune time to learn from one another and to join approaches for maximum efficacy. The articles in this special issue improve the state of our current knowledge in biocrust restoration, highlighting efforts to effectively restore biocrusts through a variety of different ecosystems, across scales and utilizing a variety of lab and field methods. This collective work provides a useful resource for the scientific community as well as land managers. 相似文献
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35.
地方认同视角下居民对农业文化遗产认知及保护态度——以福州茉莉花与茶文化系统为例 总被引:5,自引:0,他引:5
居民对农业文化遗产的认知态度影响其行为选择,并对农业文化遗产的保护及可持续发展具有重要意义。基于人文地理学及环境心理学领域的地方认同理论,选择历史认同、现实认同、情感认同及行为认同4个维度变量,通过问卷调查,以福州居民对全球重要农业文化遗产"福州茉莉花与茶文化系统"的认知及保护态度作为研究对象,并通过构建福州居民农业文化遗产认知及保护规律定量分析居民认知态度、保护行为与人口特征之间的关系。结果表明:(1)福州居民对茉莉花与茶文化系统的行为认同维度得分高于其他维度,且福州市民各维度得分均高于外来居民;(2)受访居民对农业文化遗产的地方认同与其年龄、受教育水平、收入水平及在福州居住时间长短的关系较为密切;(3)通过构建福州居民农业文化遗产认知及保护规律发现,福州居民对农业文化遗产的保护行为主要受其对该遗产项目认知态度的影响,与居民人口特征相关性较弱。拓展农业文化遗产领域的研究视角及方法,促进农业文化遗产地动态保护与可持续发展具有参考价值。 相似文献
36.
StructureSelector: A web‐based software to select and visualize the optimal number of clusters using multiple methods 下载免费PDF全文
Inferences of population genetic structure are of great importance to the fields of ecology and evolutionary biology. The program structure has been widely used to infer population genetic structure. However, previous studies demonstrated that uneven sampling often leads to wrong inferences on hierarchical structure. The most widely used ΔK method tends to identify the uppermost hierarchy of population structure. Recently, four alternative statistics (medmedk , medmeak , maxmedk and maxmeak ) were proposed, which appear to be more accurate than the previously used methods for both even and uneven sampling data. However, the lack of easy‐to‐use software limits the use of these appealing new estimators. Here, we developed a web‐based user‐friendly software structureselector to calculate the four appealing alternative statistics together with the commonly used Ln Pr(X|K) and ΔK statistics. structureselector accepts the result files of structure , admixture or faststructure as input files. It reports the “best” K for each estimator, and the results are available as HTML or tab separated tables. The program can also generate graphical representations for specific K, which can be easily downloaded from the server. The software is freely available at http://lmme.qdio.ac.cn/StructureSelector/ . 相似文献
37.
Keun Soo Ahn Sung-Tae Hong Yu Na Kang Jung Hyeok Kwon Mi Jeong Kim Tae Jun Park Yong Hoon Kim Tae Jin Lim Koo Jeong Kang 《The Korean journal of parasitology》2012,50(4):357-360
A 25-year-old Uzbek male presented with right upper abdominal pain for 20 days. On radiologic studies, a huge cystic mass was noticed in the right liver which was suspected as parasitic. The patient received right hepatic segmentectomy (segment 7), and the surgically resected mass was confirmed as cystic echinococcosis (CE), measuring 10.5 cm in its diameter. The inner surface of the cyst was bile-stained. The patient was discharged on the 8th hospital day, and was rechecked 6 months after the surgical intervention without any evidence of recurrence. The present report describes findings of an imported case of CE which represented ultrasound images of the ''ball of wool''. 相似文献
38.
Five new guaiane sesquiterpenes, 1 – 5 , were isolated from the culture broth of the endophytic fungus Xylaria sp. YM 311647, isolated from Azadirachta indica A. Juss . The structures of these compounds were elucidated on the basis of spectroscopic analyses, and their inhibitory activities against five pathogenic fungi were evaluated. All guaiane sesquiterpenes showed moderate or weak antifungal activities in a broth microdilution assay. 相似文献
39.
L. Neregård L. Sundt‐Hansen B. Th. Björnsson J. I. Johnsson 《Journal of fish biology》2008,73(10):2341-2351
The effects of growth hormone (GH) implants on aggression, and ability to win dyadic territorial conflicts were studied in brown trout Salmo trutta parr. Bovine GH or vehicle (C) was given to either the territory owner or the intruder in four treatment combinations: C and C, C and GH, GH and C, GH and GH (owner and intruder). GH‐treated intruders initiated significantly more conflicts compared to control intruders. Furthermore, GH treatment of either the owner or intruder tended to increase aggression of the intruder. This indicates that intruders have more scope for motivational increase, while the motivation of owners is already at a maximum. The GH treatment, however, did not affect the outcome of the conflict. It thus appears that growth enhancement increases intruder aggression without increasing the chance of winning the conflict, which may have implications for the effect of growth‐selected or growth‐enhanced farmed Atlantic salmon Salmo salar on wild populations. 相似文献
40.
Species diversity of the genus Osmundea (Ceramiales,Rhodophyta) in the Macaronesian region 下载免费PDF全文
María Machín‐Sánchez Florence Rousseau Line Le Gall Valéria Cassano Ana I. Neto Abel Sentíes Mutue T. Fujii María Candelaria Gil‐Rodríguez 《Journal of phycology》2016,52(4):664-681
Species diversity within the genus Osmundea in the Macaronesian region was explored by conducting a comprehensive sampling in the Azores, the Canary, and the Madeira archipelagos. Toward identification, all specimens were first observed alive to verify the absence of corps en cerise, a diagnostic character for the genus and morphometric data were measured (thallus length and width, first‐order branches length and width, branchlets length and width, cortical cell length and width in surface view, cortical cell length and width in transverse section). Specimens were sequenced for COI‐5P (39 specimens) and three species delimitation methods (Generalized Mixed Yule Coalescent, Automatic Barcode Gap Discovery method, and Poisson Tree Processes) were used to assess the threshold between infra‐ and interspecific relationships. Subsequently, one or several sequences of plastid‐encoded large subunit of RuBisCO (21 specimens) per delimited species were generated to assess the phylogenetic relationships among Macaronesian Osmundea. Moreover, for each delineated species, vegetative and reproductive anatomy was thoroughly documented and, when possible, specimens were either assigned to existing taxa or described as novel species. This integrative approach has provided data for (i) the presence of O. oederi, O. pinnatifida, and O. truncata in Macaronesia; (ii) the proposal of two novel species, O. prudhommevanreinei sp. nov. and O. silvae sp. nov.; and (iii) evidence of an additional species referred as “Osmundea sp.1,” which is a sister taxon of O. hybrida. 相似文献