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Brian M. Boom 《Brittonia》1984,36(4):425-454
A revision is presented, of the neotropical genusIsertia Schreber.Cassupa Humb. & Bonpl. is given a new status asIsertia sectionCassupa (Humb. & Bonpl.) B. M. Boom, based on differences in fruit type, number of locules in the ovary, and number of lobes of the stigma. A new combination is made at the species level,I. laevis (Triana) B. M. Boom, and a new species from Panama is described and illustrated,I. scorpioides B. M. Boom. Altogether, fourteen species and one variety are recognized in the genus.  相似文献   

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Human apolipoprotein(a), a risk factor for heart disease, has over 80% sequence identity to plasminogen. Plasminogen contains five distinct kringle domains plus a catalytic protease subunit. Human apo(a) consists of multiple copies (the number varies in individuals) of a domain resembling kringle 4, a single copy of a domain resembling kringle 5, and a protease-like domain. The recently cloned hedgehog version of apolipoprotein(a), which contains 31 nearly identical copies of plasminogen kringle 3 and lacks a protease domain, has prompted us to investigate the evolutionary history of the apolipoprotein (a) gene in mammals. Our analysis supports the nonfunctionality of the human apolipoprotein(a) protease domain, and a single (or multiple) duplication of plasminogen gene before mammal radiation, which originated apolipoprotein(a) in mammals. Received: 26 February 1996 / Accepted: 6 August 1996  相似文献   

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Chitinase enzymes hydrolyse the polysaccharide chitin, an abundant architectural component in invertebrates and fungi. Most mammals encode at least two endochitinases (CHIT1 and CHIA/AMCase), as well as several homologues encoding catalytically inactive chitinase-like proteins or chilectins (all GH18 family proteins). It is becoming increasingly apparent that chitinases and chilectins play an important role in inflammation and their over-expression is correlated with numerous pathological conditions. We have conducted a detailed phylogenomic study of this gene family in order to understand its evolutionary history and the selection forces at work. The family has undergone extensive expansion, initiating with a duplication event at the root of the vertebrate tree generating the ancestors of CHIT1 and CHIA. Our analyses indicate that two further duplications of ancestral CHIA predate the divergence of bony fishes, one leading to a newly identified paralogous group (we have termed CHIO). In fish these sequences fall into two clades bearing the hallmarks of the teleost-specific genome duplication (referred to as 3R). In tetrapods, additional duplications predate and postdate the amphibian/mammalian split and relics of some exist as pseudogenes in the human genome. Expansion and selection of chilectins is pronounced in mammals and CHI3L1 (with a proposed function in immunity) is found in most mammals but not other vertebrates, while CHI3L2 is also evident in reptiles. Notably oviductin (OVGP1) became basic and gained a glycosylated tail with its evolving role in the mammalian reproductive system. In each case, retention of the sugar-binding barrel structure has constrained positive selection to limited sites.  相似文献   

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Rova, J. H. E. & Andersson, L. 1995. A reevaluation of the tribes Hippotideae and Tammsieae (Ruhiaceae). — Nord. J. Bot. 15: 269–284. Copenhagen. ISSN 0107–055X. The genera Hippotis, Pentagonia, Sommera, and Tammsia, the hippotides, have recently been removed from their traditional position in the tribe Isertieae and proposed to form two separate tribes, Hippotideae (the three former genera) and Tammsieae (the latter one). In the most recent overview of the classification of the Ruhiaceae, the position of these tribes was considered uncertain. The morphology and micromorpho-logy of representatives of all genera were reexamined and data were analysed cladisti-cally. It is concluded that the original distinction between the Hippotideae and Tammsieae was based on faulty observations, the hippotides being uniform in ovary morphology. The cladistic analysis suggests that the hippotides form a monophyletic group, within which Tammsia is nested. It is therefore proposed that Tammsieae should he reduced to a synonym of Hippotideae. There are no indications that the hippotides should he reunited with the Isertieae. The genus Wiasemsba Klotzsch is shown to he synonymous with Tammsia, and it is argued that the genus Striolaria Ducke is synonymous with Pentagonia.  相似文献   

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The morphology and anatomy of fruits ofCoccocypselum condalia, C. geophiloides andLipostoma capitatum are discussed and illustrated. Except for the presence of a thin layer of sclerenchymatic endocarp inLipostoma, there are no significant differences in the anatomical structure of these fruits. Therefore,Lipostoma is placed under the synonymy ofCoccocypselum and the new combinationCoccocypselum capitatum is provided. The remaining species,Lipostoma sericeum, is of uncertain status.  相似文献   

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A new species of Valantia , V. lainzii Devesa & Ortega-Olivencia, endemic to the coastal zone of Granada (southern Spain) is described. The species recalls V. muralis L. in its general aspect, and V. deltoidea Brullo in the type of fructiferous body.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 331–335.  相似文献   

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One new species of the genus Spiradiclis (Rubiaceae), S. longibracteata S. Y. Liu et S. J. Wei from Guangxi Autonomous Region is described in this paper.  相似文献   

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Brian M. boom 《Brittonia》1985,37(3):317-319
Gleasonia prancei, a new species form Serra Aracá, Amazonas, Brazil, is described and illustrated.  相似文献   

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Brian M. Boom 《Brittonia》1989,41(2):129-130
Pagamea aracaënsis Boom, endemic to Serra Aracá, Brazil is described and illustrated, and its relationship toP. anisophylla Standley & Steyerm, is discussed.  相似文献   

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中国皮金龟科分类研究(鞘翅目:金龟总科)   总被引:2,自引:0,他引:2  
对皮金龟科的分类地位、分类研究历史和现状进行了简要回顾和总结,描述了皮金龟属Trox Fabricius 1775,2新种,即甘肃皮金龟T.(Trox) gansuensis sp.nov.(甘肃东部)和扁瘤皮金龟T.(Trox) placosalinus sp.nov(新疆北部)。模式标本存放于河北大学博物馆。  相似文献   

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The theory of natural selection has been vital in unifying the biological sciences and their research with a single testable metatheory. Despite a plethora of research supporting natural selection, teaching the theory of evolution remains controversial in high schools and higher education (Wilson et al. 2009; Scott 1997). In this article, we sample the attitudes toward evolution of 170 faculty and graduate and undergraduate students in family studies and human development programs from across the United States to determine whether resistances toward evolution remain and to describe the correlates of these resistances. Results reveal that an individual’s prosocial meliorist attitudes, religious ideation, and his or her reported interest in and knowledge of evolution all uniquely contribute to whether they report evolutionary theory as being applicable to their area of research interests. We discuss the relevance of including evolutionary theory within family studies and human development research programs and make suggestions for how to implement an evolutionary studies program (Wilson et al. 2009).  相似文献   

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Cathepsin L family, an important cysteine protease found in lysosomes, is categorized into cathepsins B, F, H, K, L, S, and W in vertebrates. This categorization is based on their sequence alignment and traditional functional classification, but the evolutionary relationship of family members is unclear. This study determined the evolutionary relationship of cathepsin L family genes in vertebrates through phylogenetic construction. Results showed that cathepsins F, H, S and K, and L and V were chronologically diverged. Tandem-repeat duplication was found to occur in the evolutionary history of cathepsin L family. Cathepsin L in zebrafish, cathepsins S and K in xenopus, and cathepsin L in mice and rats underwent evident tandem-repeat events. Positive selection was detected in cathepsin L-like members in mice and rats, and amino acid sites under positive selection pressure were calculated. Most of these sites appeared at the connection of secondary structures, suggesting that the sites may slightly change spatial structure. Severe positive selection was also observed in cathepsin V (L2) of primates, indicating that this enzyme had some special functions. Our work provided a brief evolutionary history of cathepsin L family and differentiated cathepsins S and K from cathepsin L based on vertebrate appearance. Positive selection was the specific cause of differentiation of cathepsin L family genes, confirming that gene function variation after expansion events was related to interactions with the environment and adaptability.  相似文献   

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Psychotria waasii Sohmer, a replacement name for the later homonym Psychotria filipes Hook.f., has been found illegitimate because of being superfluous when published. The new combination Psychotria josephi (Kuntze) Kottaim. is proposed based on the earliest available name Uragoga josephi Kuntze.  相似文献   

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