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81.
《Cell》2022,185(23):4409-4427.e18
82.
TROY G. MURPHY TIFFANY T. PHAM 《Biological journal of the Linnean Society. Linnean Society of London》2012,106(3):673-681
Coloration plays an important role in sexual and social communication, and in many avian species both males and females maintain elaborate colours. Recent research has provided strong support for the hypothesis that elaborate female traits can be maintained by sexual or social selection; however, most research on female ornamentation has focused on pigment‐based colours, and less is known about how structural colours are maintained. Both sexes of the turquoise‐browed motmot (Eumomota superciliosa) have a blue‐green racket‐tipped tail, and it remains unknown if tail coloration serves as a sexual or social signal in one or both sexes. Here, we describe sexual dichromatism in the blue‐green portion of the tail racket, and we test for a relationship between coloration and condition, as indicated by growth bars. Tail colour of both sexes has a similar spectral shape, and there is significant, although moderate, sexual dichromatism: males are brighter than females, and males have marginally greater blue‐green saturation than females. The length of feather grown per day is positively related to overall feather brightness, but this relationship is only present in males. The relationship between male coloration and condition suggests that tail colour has the potential to convey information about individual quality during mate choice or contest competition. The lack of a similar relationship in females suggests that female tail colour does not convey the same condition‐dependent information that we suggest may be reflected by male colour. Female tail colour may therefore reflect other aspects of condition, be involved in other (non‐condition‐dependent) forms of communication, or be expressed as a non‐functional byproduct of genetic correlation between the sexes. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 106 , 673–681. 相似文献
83.
Núria Cerdà‐Costa Francesc Xavier Gomis‐Rüth 《Protein science : a publication of the Protein Society》2014,23(2):123-144
The cleavage of peptide bonds by metallopeptidases (MPs) is essential for life. These ubiquitous enzymes participate in all major physiological processes, and so their deregulation leads to diseases ranging from cancer and metastasis, inflammation, and microbial infection to neurological insults and cardiovascular disorders. MPs cleave their substrates without a covalent intermediate in a single‐step reaction involving a solvent molecule, a general base/acid, and a mono‐ or dinuclear catalytic metal site. Most monometallic MPs comprise a short metal‐binding motif (HEXXH), which includes two metal‐binding histidines and a general base/acid glutamate, and they are grouped into the zincin tribe of MPs. The latter divides mainly into the gluzincin and metzincin clans. Metzincins consist of globular ~130–270‐residue catalytic domains, which are usually preceded by N‐terminal pro‐segments, typically required for folding and latency maintenance. The catalytic domains are often followed by C‐terminal domains for substrate recognition and other protein–protein interactions, anchoring to membranes, oligomerization, and compartmentalization. Metzincin catalytic domains consist of a structurally conserved N‐terminal subdomain spanning a five‐stranded β‐sheet, a backing helix, and an active‐site helix. The latter contains most of the metal‐binding motif, which is here characteristically extended to HEXXHXXGXX(H,D). Downstream C‐terminal subdomains are generally shorter, differ more among metzincins, and mainly share a conserved loop—the Met‐turn—and a C‐terminal helix. The accumulated structural data from more than 300 deposited structures of the 12 currently characterized metzincin families reviewed here provide detailed knowledge of the molecular features of their catalytic domains, help in our understanding of their working mechanisms, and form the basis for the design of novel drugs. 相似文献
84.
David L. Remington P?ivi H. Leinonen Johanna Lepp?l? Outi Savolainen 《Genetics》2013,195(3):1087-1102
Costs of reproduction due to resource allocation trade-offs have long been recognized as key forces in life history evolution, but little is known about their functional or genetic basis. Arabidopsis lyrata, a perennial relative of the annual model plant A. thaliana with a wide climatic distribution, has populations that are strongly diverged in resource allocation. In this study, we evaluated the genetic and functional basis for variation in resource allocation in a reciprocal transplant experiment, using four A. lyrata populations and F2 progeny from a cross between North Carolina (NC) and Norway parents, which had the most divergent resource allocation patterns. Local alleles at quantitative trait loci (QTL) at a North Carolina field site increased reproductive output while reducing vegetative growth. These QTL had little overlap with flowering date QTL. Structural equation models incorporating QTL genotypes and traits indicated that resource allocation differences result primarily from QTL effects on early vegetative growth patterns, with cascading effects on later vegetative and reproductive development. At a Norway field site, North Carolina alleles at some of the same QTL regions reduced survival and reproductive output components, but these effects were not associated with resource allocation trade-offs in the Norway environment. Our results indicate that resource allocation in perennial plants may involve important adaptive mechanisms largely independent of flowering time. Moreover, the contributions of resource allocation QTL to local adaptation appear to result from their effects on developmental timing and its interaction with environmental constraints, and not from simple models of reproductive costs. 相似文献
85.
86.
《Cell》2022,185(16):3025-3040.e6
87.
88.
89.
镰刀菌主要为植物致病菌,但也可引起严重人类感染。镰刀菌病临床表现形式多样,本文主要综述相关的皮肤感染,分为局限性皮肤感染及播散性感染,诊断多较困难。由于该属真菌对抗真菌药物存在天然耐药,播散性镰刀菌病死亡率可达80%-90%。本文对Medline和中文文献数据库中的相关文献进行了系统查阅和分析,综合归纳了镰刀菌所致皮肤感染的致病种、地域分布、危险因子、临床表现形式、药物敏感性及其诊疗方案等,该综述对全面了解镰刀菌病的特征及对临床医师对本病的诊断具有重要的意义。 相似文献
90.
目的:探讨食道癌组织微小RNA-21(miR-21)、微小RNA-182(miR-182)表达与临床病理特征及预后的关系。方法:选取2011年4月到2013年7月期间在我院接受手术治疗的食道癌患者84例,取患者的癌组织和癌旁正常组织作为检验标本,比较癌组织和癌旁正常组织中miR-21、mi R-182的表达水平,并分析食道癌组织中mi R-182、mi R-21的表达与临床病理特征及预后的关系。结果:癌组织中mi R-21、mi R-182的相对表达量明显高于癌旁正常组织,差异有统计学意义(P<0.05)。食道癌组织中mi R-21的表达与淋巴结转移、临床分期有关(P<0.05),与性别、年龄、分化程度、肿瘤大小无关(P>0.05);食道癌患者癌组织中miR-182的表达与年龄、性别、肿瘤大小无关(P>0.05),与分化程度、临床分期、淋巴结转移有关(P<0.05)。食道癌癌组织中miR-21、miR-182高表达患者的中位生存时间均低于低表达患者,差异有统计学意义(P<0.05)。结论:食道癌组织mi R-21、mi R-182表达与患者的部分临床病理特征及预后有关,两者有望成为食道癌新的治疗靶点。 相似文献