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11.
Olsson M Madsen T Ujvari B Wapstra E 《Evolution; international journal of organic evolution》2004,58(4):906-909
We demonstrate that extending copulation enhances probability of paternity in sand lizards and that determinants of copulation duration depend on a males' mating order (first or second). First males, with no information on presence of rivals, extend copulation when mating with a more fecund female. Second males, however, adjust copula duration in relation to a first male's relatedness with his female, which there is reason to believe can be deduced from the MHC-related odor of the copulatory plug. Male-female relatedness negatively influences a male's probability of paternity, and when second males are in a favored role (i.e., the first male is the one more closely related to the female), second males transfer larger ejaculates, resulting in higher probability of paternity. This result corroborates predictions from recent theoretical models on sperm expenditure theory incorporating cryptic female choice and sexual conflict. More specifically, the results conform to a "random roles" model, which depicts males as being favored by some females and disfavored by others, but not to a "constant-type" model, in which a male is either favored or disfavored uniformly by all females in a population. 相似文献
12.
Variation between mouse major urinary protein genes isolated from a single inbred line 总被引:13,自引:0,他引:13
We describe ten Charon 4A genomic DNA clones from BALB/c mice which include at least seven different major urinary protein (MUP) genes. We have established the orientation of all seven sequences, and have placed six of them in precise register by means of restriction site maps and Southern blot hybridization with cloned cDNA sequences. Four of the seven genomic sequences (family I sequences) form hybrids with six independent cDNA clones that have a high thermal stability and hybridize more strongly with mRNA from three inbred mouse lines. Hybrids between the remaining three genomic sequences and the cDNA clones have a lower thermal stability and hybridize less strongly with mRNA from the three inbred lines. Homologies between different cloned sequences extend over as much as 15 kb. No clone contains parts of two MUP genes, and no homology has been detected between the 3' flanking region of one MUP gene and the 5' flanking region of another. 相似文献
13.
Rika Kamei Mana Miyakoda Takahiko Tamura Daisuke Kimura Kiri Honma Kazumi Kimura Katsuyuki Yui 《Microbiology and immunology》2013,57(3):213-223
14.
McLuskey K Paterson NG Bland ND Isaacs NW Mottram JC 《The Journal of biological chemistry》2010,285(50):39249-39259
Oligopeptidase B (OPB) is a serine peptidase with dibasic substrate specificity. It is found in bacteria, plants, and trypanosomatid pathogens, where it has been identified as a virulence factor and potential drug target. In this study we expressed active recombinant Leishmania major OPB and provide the first structure of an oligopeptidase B at high resolution. The crystallographic study reveals that OPB comprises two domains, a catalytic and a propeller domain, linked together by a hinge region. The structure has been determined in complex with the oligopeptide, protease-inhibitor antipain, giving detailed information on the enzyme active site and extended substrate binding pockets. It shows that Glu-621 plays a critical role in the S1 binding pocket and, along with Phe-603, is largely responsible for the enzyme substrate specificity in P1. In the S2 binding pocket, Tyr-499 was shown to be important for substrate stability. The structure also allowed an investigation into the function of residues highlighted in other studies including Glu-623, which was predicted to be involved in the S1 binding pocket but is found forming an inter-domain hydrogen bond. Additional important salt bridges/hydrogen bonds between the two domains were observed, highlighting the significance of the domain interface in OPB. This work provides a foundation for the study of the role of OPBs as virulence factors in trypanosomatids. It could facilitate the development of specific OPB inhibitors with therapeutic potential by exploiting its unique substrate recognition properties as well as providing a model for OPBs in general. 相似文献
15.
BACKGROUND AND AIMS: Species' 2C-values (mass of DNA in G(1) phase 2n nuclei) vary by at least four orders of magnitude among seed plants. The 2C-value has been shown to be co-ordinated with a number of other species traits, and with environmental variables. A prediction that species 2C-values are negatively related to leaf life span (LL) and leaf mass per area (LMA) is tested. These leaf traits are components of a major dimension of ecological variation among plant species. METHODS: Flow cytometry was used to measure the 2C-values for 41 Australian seed plant species, 40 of which were new to the literature. Where possible, LL and LMA data from the global literature were combined with 2C-values from our data set and online C-value databases. KEY RESULTS: Across all species, weak positive relationships were found between 2C-values and both LL and LMA; however, these did not reflect the relationships within either angiosperms or gymnosperms. Across 59 angiosperm species, there were weak negative relationships between 2C-values and both LL (r2 = 0.13, P = 0.005) and LMA (r2 = 0.15, P = 0.002). These relationships were the result of shifts to longer LL and greater LMA in woody compared with herbaceous growth forms, with no relationships present within growth forms. It was not possible to explain a positive relationship between 2C-values and LMA (r2 = 0.30, P = 0.024) across 17 gymnosperm species. The 2C-value was not related to LL or LMA either across species within orders (except for LMA among Pinales), or as radiation divergences in a model phylogeny. CONCLUSIONS: Gymnosperms appear to vary along a spectrum different from angiosperms. Among angiosperms, weak negative cross-species relationships were associated with growth form differences, and traced to a few divergences deep in the model phylogeny. These results suggest that among angiosperms, nuclear DNA content and leaf strategy are unrelated. 相似文献
16.
The major histocompatibility complex (MHC) genes are extremely polymorphic and this variation is assumed to be maintained by balancing selection. Cyclic interactions between pathogens and their hosts could generate such selection, and specific MHC alleles or heterozygosity at certain MHC loci have been shown to confer resistance against particular pathogens. Here we compare the temporal variation in allele frequencies of 23 MHC class I alleles with that of 23 neutral microsatellite markers in adult great reed warblers (a passerine bird) in nine successive cohorts. Overall, the MHC alleles showed a significantly higher variation in allele frequencies between cohorts than the microsatellite alleles, using a multi-variate genetic analysis (amova). The frequency of two specific MHC alleles, A3e (P = 0.046) and B4b (P = 0.0018), varied more between cohorts than expected from random, whereas none of the microsatellite alleles showed fluctuations exceeding the expectation from stochastic variation. These results imply that the variation in MHC allele frequencies between cohorts is not a result of demographic events, but rather an effect of selection favouring different MHC alleles in different years. 相似文献
17.
粳稻穗角与稻米品质的相关性及稻米品质遗传分析 总被引:4,自引:1,他引:4
测定了粳稻直立穗品种丙8979与弯曲穗品种C堡杂交组合的P1、P2及其重组自交系349个株系的穗角和10个稻米品质性状, 分析了穗角与稻米品质性状之间的相关性, 并运用主基因+多基因混合遗传模型, 对稻米品质10个性状进行了遗传分析。结果表明,穗角与糙米率、整精米率、垩白粒率、垩白度、糊化温度、胶稠度和直链淀粉含量均无显著相关; 与精米率呈显著正相关(r=0.124*); 与粒长和长宽比均呈极显著正相关(相关系数分别为0.470**和0.241**)。糙米率、精米率和直链淀粉含量均受2对主基因+多基因控制, 2对主基因具有累加作用和加性×加性的上位性作用; 整精米率、粒长、长宽比和胶稠度受2对加性-上位性主基因+多基因控制;垩白粒率、垩白度和糊化温度均受3对加性-上位性主基因+多基因控制。糙米率、精米率、整精米率、垩白粒率、垩白度和糊化温度6个品质性状以主基因遗传为主,粒长、长宽比、胶稠度和直链淀粉含量4个性状以多基因遗传为主。 相似文献
18.
《Bioscience, biotechnology, and biochemistry》2013,77(3):556-560
We encountered a fourth case of honey allergy in Japan. We characterized and identified the IgE-binding proteins in honey using the serum of a honey-allergenic patient. Immunoblot analysis revealed that IgE in the patient serum specifically bound to four proteins in each honey sample. At least three of these IgE-binding proteins were N-linked glycoproteins. To identify the 60-kDa IgE-binding protein in dandelion honey, the N-terminal sequences of the fragmented protein were analyzed, revealing the protein to be major royal jelly protein 1 (MRJP 1). Three IgE-binding proteins removed of N-linked oligosaccharide showed a large reduction in IgE-binding activity as compared with the intact protein. This suggests that the carbohydrates in the IgE-binding proteins are a major epitope for patient IgE. 相似文献
19.
Cha IS Kwon J Park SH Nho SW Jang HB Park SB del Castillo CS Hikima J Aoki T Jung TS 《Journal of Proteomics》2012,75(17):5166-5175
The proteomic response to bacterial infection in a teleost fish (Paralichthys olivaceus) infected with Streptococcus parauberis was analyzed using label-free protein quantitation coupled with LC-MS(E) tandem mass spectrometry. A total of 82 proteins from whole kidney, a major lymphoid organ in this fish, were found to be differentially expressed between healthy and diseased fish analyzed 6, 24, 72 and 120 h post-infection. Among the differentially expressed proteins, those involved in mediating immune responses (e.g., heat shock proteins, cathepsins, goose-type lysozyme and complement components) were most significantly up-regulated by infection. In addition, cell division cycle 48 (CDC48) and calreticulin, which are associated with cellular recovery and glycoprotein synthesis, were up-regulated in the universal protein group, whereas the other proteins in that group were down-regulated. There was continuous activation of expression of immune-associated proteins during infection, but there was also loss of expression of proteins not involved in immune function. We expect that our findings regarding immune response at the protein level would offer new insight into the systemic response to bacterial infection of a major immune organ in teleost fish. 相似文献
20.