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排序方式: 共有1130条查询结果,搜索用时 53 毫秒
21.
Jukka Keklinen Annalaura Jokiniemi Matti Janhunen Hannu Huuskonen 《Journal of evolutionary biology》2020,33(5):584-594
In a large majority of animal species, the only contribution of males to the next generation has been assumed to be their genes (sperm). However, along with sperm, seminal plasma contains a wide array of extracellular factors that have many important functions in reproduction. Yet, the potential intergenerational effects of these factors are virtually unknown. We investigated these effects in European whitefish (Coregonus lavaretus) by experimentally manipulating the presence and identity of seminal plasma and by fertilizing the eggs of multiple females with the manipulated and unmanipulated semen of several males in a full‐factorial breeding design. The presence of both own seminal plasma and foreign seminal plasma inhibited sperm motility, and the removal of own seminal plasma decreased embryo survival. Embryos hatched significantly earlier after both semen manipulations than in control fertilizations; foreign seminal plasma also increased offspring aerobic swimming performance. Given that our experimental design allowed us to control potentially confounding sperm‐mediated (sire) effects and maternal effects, our results indicate that seminal plasma may have direct intergenerational consequences for offspring phenotype and performance. This novel source of offspring phenotypic variance may provide new insights into the evolution of polyandry and mechanisms that maintain heritable variation in fitness and associated female mating preferences. 相似文献
22.
Mariano Alvarez Andrew Bleich Kathleen Donohue 《Evolution; international journal of organic evolution》2020,74(10):2265-2280
Phenotypes respond to environments experienced directly by an individual, via phenotypic plasticity, or to the environment experienced by ancestors, via transgenerational environmental effects. The adaptive value of environmental effects depends not only on the strength and direction of the induced response but also on how long the response persists within and across generations, and how stably it is expressed across environments that are encountered subsequently. Little is known about the genetic basis of those distinct components, or even whether they exhibit genetic variation. We tested for genetic differences in the inducibility, temporal persistence, and environmental stability of transgenerational environmental effects in Arabidopsis thaliana. Genetic variation existed in the inducibility of transgenerational effects on traits expressed across the life cycle. Surprisingly, the persistence of transgenerational effects into the third generation was uncorrelated with their induction in the second generation. Although environmental effects for some traits in some genotypes weakened over successive generations, others were stronger or even in the opposite direction in more distant generations. Therefore, transgenerational effects in more distant generations are not merely caused by the retention or dissipation of those expressed in prior generations, but they may be genetically independent traits with the potential to evolve independently. 相似文献
23.
24.
Ram Parikshan Kumar 《BioEssays : news and reviews in molecular, cellular and developmental biology》2009,31(8):822-825
Polycomb group (PcG) proteins maintain the expression state of PcG‐responsive genes during development of multicellular organisms. Recent observations suggest that “the H3K27me3 modification” acts to maintain Polycomb repressive complex (PRC) 2, the enzyme that creates this modification, on replicating chromatin. This could in turn promote propagation of H3K27me3 on newly replicated daughter chromatin, and promote recruitment of PRC1. Other work suggests that PRC1‐class complexes can be maintained on replicating chromatin, at least in vitro, independently of H3K27me3. Thus, histone modifications and PcG proteins themselves may both be maintained through replication. 相似文献
25.
Wolfgang Forstmeier Claudia Burger Katja Temnow Sébastien Derégnaucourt 《Evolution; international journal of organic evolution》2009,63(8):2114-2130
Animal vocalizations play an important role in individual recognition, kin recognition, species recognition, and sexual selection. Despite much work in these fields done on birds virtually nothing is known about the heritability of vocal traits in birds. Here, we study a captive population of more than 800 zebra finches ( Taeniopygia guttata ) with regard to the quantitative genetics of call and song characteristics. We find very high heritabilities in nonlearned female call traits and considerably lower heritabilities in male call and song traits, which are learned from a tutor and hence show much greater environmental variance than innate vocalizations. In both sexes, we found significant heritabilities in several traits such as mean frequency and measures of timbre, which reflect morphological characteristics of the vocal tract. These traits also showed significant genetic correlations with body size, as well as positive genetic correlations between the sexes, supporting a scenario of honest signaling of body size through genetic pleiotropy ("index signal"). In contrast to such morphology-related voice characteristics, classical song features such as repertoire size or song length showed very low heritabilities. Hence, these traits that are often suspected to be sexually selected would hardly respond to current directional selection. 相似文献
26.
Rumela Chakrabarti Sally Shepardson Moumita Karmakar Richard Trdan Jennifer Walker Ramdas Shandilya Don Stewart Srinivasan Vijayaraghavan Walter Hoeh 《Development, growth & differentiation》2009,51(5):511-519
Our previous study documented a reproductive function for the male‐transmitted mitochondrial DNA (mtDNA)‐encoded cytochrome c oxidase subunit II (MCOX2) protein in a unionoid bivalve. Here, immunoblotting, immunohistochemistry and immunoelectron microscopy analyses demonstrate that the female‐transmitted protein (FCOX2) is: (i) expressed in both male and female gonads; (ii) maximally expressed in ovaries just prior to the time of the annual fertilization event; (iii) displayed in the cytoplasm and more strongly in the plasma membrane (microvilli), vitelline matrix and vitelline envelope of mature ovarian eggs; and (iv) strongly localized to the vitelline matrix of some eggs just prior to fertilization. These findings represent evidence for the extra‐mitochondrial localization of an mtDNA‐encoded gene product and are consistent with multifunctionality for FCOX2 in eggs. 相似文献
27.
Histone methylation is believed to play important roles in epigenetic memory in various biological processes. However, questions
like whether the methylation marks themselves are faithfully transmitted into daughter cells and through what mechanisms are
currently under active investigation. Previously, methylation was considered to be irreversible, but the recent discovery
of histone lysine demethylases revealed a dynamic nature of histone methylation regulation on four of the main sites of methylation
on histone H3 and H4 tails (H3K4, H3K9, H3K27 and H3K36). Even so, it is still unclear whether demethylases specific for the
remaining two sites, H3K79 and H4K20, exist. Furthermore, besides histone proteins, the lysine methylation and demethylation
also occur on non-histone proteins, which are probably subjected to similar regulation as histones. This review discusses
recent progresses in protein lysine methylation regulation focusing on the above topics, while referring readers to a number
of recent reviews for the biochemistry and biology of these enzymes 相似文献
28.
Based on the traditional polygene inheritance model of quantitative traits,the author suggests the major gene and polygene mixed inheritance model.The model was considered as a general one,while the pure major gene and pure polygene inheritance model was a specific case of the general model.Based on the proposed theory,the author established the segregation analysis procedure to study the genetic system of quantitative traits of plants.At present,this procedure can be used to evaluate the genetic effect of individual major genes (up to two to three major genes),the collective genetic effect of polygene,and their heritability value.This paper introduces how to establish the procedure,its main achievements,and its applications.An example is given to illustrate the steps,methods,and effectiveness of the procedure. 相似文献
29.
A. A. GHEYAS M. CAIRNEY A. E. GILMOUR M. A. SATTAR T. K. DAS B. J. McANDREW D. J. PENMAN J. B. TAGGART 《Molecular ecology resources》2006,6(3):656-659
Captive populations of silver carp (Hypophthalmichthys molitrix), a major aquaculture species in Asia, would undoubtedly benefit from genetic monitoring and improvement programs. We report the isolation and preliminary characterization of 16 microsatellite loci derived from both conventional and microsatellite‐enriched libraries. Inheritance studies confirmed the allelic nature of observed polymorphisms at all loci, while identifying null alleles at two loci. These loci, having varying degrees of polymorphism, should provide useful markers for applied genetic studies. A high degree of cross‐amplification among 10 other cyprinid species suggests that these loci may have more widespread utility. 相似文献
30.