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1.
Abstract. The genus Lypusa Zeller, 1852 has been assigned to Tineoidea (Lepidoptera) with varying family positions. The systematic affinities of this genus, currently placed in its own family Lypusidae, were studied using extensive data derived from larval, pupal and adult morphology and certain behavioural traits. In total, 193 characters were considered. On the basis of the results of a parsimony analysis, Lypusa is transferred to the superfamily Gelechioidea, in a monophyletic, exclusively Palaearctic assemblage with the genera Amphisbatis and Pseudatemelia. Several phylogenetically relevant characters support this position, including similarly constructed larval cases, densely porose larval head, and a modification of the pupal abdominal segment 8. The composition of the family Amphisbatidae is discussed and it is proposed that it be delimited as comprising solely the Palaearctic genera Pseudatemelia, Amphisbatis and Lypusa. A detailed diagnosis of the genus Lypusa is given.  相似文献   

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Liu Y  Zhu Q  Zhu N 《Genetica》2008,133(1):31-35
We report that the GAGE gene family of human Cancer/testis antigen (CTA) genes is likely to be in an early stage of its evolution. Members of this gene family are tandemly arranged on the X chromosome only in human, chimpanzee and macaque genomes and share a very high similarity. Phylogenetic trees show that the GAGE gene family began to duplicate after the split of human and chimpanzee. The estimated ages of the duplication events range from 4 million years ago to the present. The Ka/Ks values between the duplicates are significantly greater than 1, indicating that the mutation rate is higher in coding regions than non-coding regions of the genes, which suggests that the GAGE gene family is under positive selection. These findings indicate that the GAGE gene family may be a newly formed gene family undergoing rapid functional evolution. Yang Liu and Qiyun Zhu contributed equally to this work.  相似文献   

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The main objective of this investigation was to study the Actinomycetales community in a Tunisian agricultural soil amended with different amounts of municipal solid waste compost (MSWC) or farmyard manure (FM). It was shown, by using the 16S rDNA polymerase chain reaction—restriction fragment length polymorphism and sequencing methods for Actinomycetales isolates, tow major clusters. The cluster SI is composed of tow related families: Streptomycetaceae, dominant family and Pseudonocardiaceae. However, SII is composed of Nocardioidaceae family. The application of FM or MSWC increases the Actinomycetales number and affects their diversity by inhibition, stimulation or contribution of some species in soil. It was also shown, by the application of molecular techniques to soil samples using selective primers, that these three groups of Actinomycetales remain dominant even after 5 years of organic amendment application in soil.  相似文献   

4.
The major satellite DNAs of the dioecious plant Silene latifolia are represented by the repetitive sequences X43.1, RMY1 and members of the SacI family, which are located at the distal ends of chromosomes. To characterize the satellite DNAs at the distal ends of the chromosomes in S. latifolia (Sl-distal-satDNA), we isolated a bacterial artificial chromosome clone (number 15B12) that contained multiple repeat sequences with KpnI restriction sites, and subcloned a portion of this sequence into a plasmid vector. Sequencing analysis confirmed that recognition or degenerate sites for KpnI were repeated 26 times at intervals of 310–324 bp in the inserted DNA. The phylogenetic tree that was constructed with the 26 KpnI repeat units contained clustered branches that were independent of the SacI family. It is clear that the KpnI repeat belongs to an Sl-distal-satDNA family that is distinct from the SacI family. We designated this family as "KpnI" after the restriction enzyme that does not have a site in the SacI family. Multi-colored fluorescent in situ hybridization was performed with the KpnI family and RMY1 probes under high stringency conditions. The results suggest that chromosome 7 is unique and that it carries the KpnI family at only one end.  相似文献   

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The Groucho/Tle family of corepressor proteins has important roles in development and in adult tissue in both Protostomes and Deuterostomes. In Drosophila, a single member of this family has been identified. Unlike in Protostomes, most Deutrostomes contain more than two full-length Tle genes. In this study, I analyse the genomic organization and phylogenetic relationship between the long and short forms of the Groucho/Tle family members in Chordata. The genomic location and sequence similarities suggest that Aes/Grg5 and Tle6/Grg6 arose from duplication of the Tle2 gene; each evolved independently and acquired new functions as negative regulators of the other Tle proteins. Based on these data, a model for Groucho/Tle gene evolution is proposed. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

7.
The well-preserved skull of the diodontid fish Pshekhadiodon parini Bannikov et Tyler, 1997 from the Eocene of the North Caucasus has plesiomorphic conditions for four character that are apomorphic in all extant taxa, and the family Diodontidae is herein separated into two subfamilies, the Diodontinae for all of the extant taxa and the Pshekhadiodontinae for Pshekhadiodon and very tentatively for the three other Eocene taxa of the family, all from Monte Bolca, Italy.  相似文献   

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Using the method of molecular-genetic analysis, we investigated the genus Neozoarces (subfamily Neozoarcinae) to reveal its relationships and position in the system of the suborder Zoacoidei. Comparison with representatives of other families of this suborder demonstrated that the lowest level of differences is observed between Neozoarces and subfamilies of the family Zoarcidae (the mean value of genetic divergence is 11.9%) with which it forms a general cluster on the phylogenetic tree. From representatives of the family Stichaeidae, Neozoarces differs at the same level (13.9%) as from the families Bathymasteridae, Pholidae, Ptilichthyidae, and Zaproridae (14.0%). The results of investigations confirm the viewpoint suggested by Makushok (1961) who included, for the first time, the subfamily Neozoarcinae to the family Zoarcidae on the basis of comparative morphological investigation of these groups.  相似文献   

10.
Here we describe a novel gene that is highly expressed in the corpora allata, an endocrine organ responsible for synthesizing juvenile hormones (JHs), in the fruit fly, Drosophila melanogaster Meigen. We isolated an enhancer-trap line in which the transgene was inserted at the locus CG32103, which encodes a mitochondrial carrier family protein with calcium-binding motifs. RNA in situ hybridization revealed that CG32103 is predominantly expressed in the corpora allata in D. melanogaster larvae. Putative orthologs of CG32103 are conserved in many insect species. Mitochondrial carriers are responsible for transporting metabolites across the inner mitochondrial membrane. Given that both mitochondrial membrane transport and cytoplasmic calcium signaling are important for JH biosynthesis regulation, we speculated that CG32103 represents a new member of the family of JH biosynthesis regulators in insects.  相似文献   

11.
《Journal of morphology》2017,278(11):1570-1576
The crescent sculpture of the so‐called “Xestoleberis‐spot” develops inside the calcified valve of the family Xestoleberididae. Electron microscopic observations on both, intermoult and postmoult stages of Xestoleberis species reveal that the “Xestoleberis‐spot” system consists of three elements; two calcified chambers, a vesicle of electron‐dense material and an uncalcified procuticle. The formation and function of the “Xestoleberis‐spot” system are discussed. In conclusion, the “Xestoleberis‐spot” system functions as the muscle attachment site for several antennal muscles, and provides the material for chitinous fibers in the exocuticle of outer lamella. The unique cuticular structures of the family Xestoleberididae are due to the “Xestoleberis‐spot” system.  相似文献   

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Background  

Long wave-sensitive (LWS) opsin genes have undergone multiple lineage-specific duplication events throughout the evolution of teleost fishes. LWS repertoire expansions in live-bearing fishes (family Poeciliidae) have equipped multiple species in this family with up to four LWS genes. Given that color vision, especially attraction to orange male coloration, is important to mate choice within poeciliids, LWS opsins have been proposed as candidate genes driving sexual selection in this family. To date the genomic organization of these genes has not been described in the family Poeciliidae, and little is known about the mechanisms regulating the expression of LWS opsins in any teleost.  相似文献   

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The survival of an organism depends on its ability to respond to its environment through its senses. The sense of touch is one of the most vital; still, it is the least understood. In the process of touch sensation, a mechanical stimulus is converted into electrical signals. Groundbreaking electrophysiological experiments in organisms ranging from bacteria to mammals have suggested that this conversion may occur through the activation of ion channels that gate in response to mechanical stimuli. However, the molecular identity of these channels has remained elusive for a very long time. Breakthroughs in our understanding of the cellular and molecular mechanisms of touch sensation have come from the analysis of touch-insensitive mutants in model organisms such as Caenorhabditis elegans and Drosophila melanogaster. This review will focus on the elegant genetic, molecular, imaging, and electrophysiological studies that demonstrate that a channel complex composed of two members of the DEG/ENaC gene family of channel subunits (named for the C. elegans degenerins and the related mammalian epithelial amiloride-sensitive Na channel), MEC-4 and MEC-10, and accessory subunits is gated by mechanical forces in touch-sensing neurons from C. elegans. I also report here electrophysiological and behavioral studies employing knockout mice that have recently shown that mammalian homologues of MEC-4, MEC-10, and accessory subunits are needed for normal mechanosensitivity in mouse, suggesting a conserved function for this channel family across species. The C. elegans genome encodes 28 DEG/ENaC channels: I discuss here the global role of DEG/ENaCs in mechanosensation, reporting findings on the role of other three nematode DEG/ENaCs (UNC-8, DEL-1, and UNC-105) in mechanosensitive and stretch-sensitive behaviors. Finally, this review will discuss findings in which members of another family of ion channels, the Transient Receptor Potential channels family, have been implicated in mechanosensitive behaviors in organisms ranging from C. elegans to mammals.  相似文献   

17.
Pachycheles stevensii Stimpson, 1858 is the only species of the family Porcellanidae (Decapoda, Anomura) living in the Russian waters of the Sea of Japan. The morphology of prezoeal larval stages of this crab obtained under laboratory conditions for the first time was studied and described in detail.Original Russian Text Copyright © 2005 by Biologiya Morya, Kornienko.  相似文献   

18.
The taxonomic position of a new pollen‐feeding fossil beetle from Spanish amber (late Albian, 105 Ma) is analysed. A phylogenetic analysis allows me to accommodate Darwinylus marcosi gen. et sp. nov. in the Polyphaga: Oedemeridae within current limits for the family, which clearly belongs in the subfamily Oedemerinae. It corresponds to the oldest definitive record for the family. Some autapomorphies, mainly in antennae, are observable in the fossil compared with extant members of the family. A discussion about these problematic characters and the evolution of the family is proposed.  相似文献   

19.
Scirpentriol and its seven acetylated derivatives comprise a family of type-A trichothecene toxins produced by several species of Fusarium fungi. Out of this group 4,15-diacetoxyscirpenol has attracted most attention. It elicits toxic responses in several species and was detected in a variety of substrates. Out of the three possible monoacetylated derivatives 15-monoacetoxyscirpenol and the parent alcohol scirpentriol received some attention, whereas the remaining members of the family were mentioned in few reports. The present review deals with the structure, biosynthesis, analysis and toxicity of scirpentriol toxins. Formation by Fusarium species as well as culture conditions used for toxigenicity studies are reviewed; data about the natural occurrence of scirpentriol toxins in different cereal types, cereal associated products as well as in non-grain matrices including potato and soya bean are reported. Basing on literature reports about the toxicity of scirpentriol toxins an attempt is made to summarise the state of knowledge for risk evaluation for human and animal health.  相似文献   

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