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Nakajima T 《Bio Systems》2012,108(1-3):34-44
Epistatic interactions between genes in the genome constrain the accessible evolutionary paths of lineages. Two factors involving epistasis that can affect the evolutionary path and fate of lineages were investigated. The first factor concerns the impact of competition with another species lineage that has different epistatic constraints. Five enteric bacterial populations were evolved by point mutation in medium containing a single limiting resource. Single-species and two-species cultures were used to determine whether different asexual lineages have different capacities for producing variants due to epistatic constraints, and whether their survival is determined by local inter-lineage competition with different species. Local inter-lineage competition quickly resulted in one successful lineage, with another lineage becoming extinct before finding a higher peak. The second factor concerns a peak-shifting process, and whether the sexual recombination between different demes can cause peak shifts was investigated. An Escherichia coli population consisting of a male (Hfr) and female strain (F(-)) was evolved in a single limiting resource and compared to evolving populations containing the male or female strain alone. The E. coli sexual lineage was successful due to its ability to escape lower peaks and reach a higher peak, not because of a rapid approach to the nearest local peak the male or female asexual lineage could reach. The data in this study demonstrate that lineage survivability can be determined by the ability to produce beneficial mutations and checked by local competition between lineages of different species. Interspecific competition may prevent a population from evolving through crossing fitness valleys or adaptive ridges if it requires many generations to achieve peak shifts. The data also show that genomic recombination between different conspecific lineages can rapidly carry the combined lineage to a higher peak. 相似文献
3.
In insect societies, worker vs. queen development (reproductive caste) is typically governed by environmental factors, but many Pogonomyrmex seed-harvester ants exhibit strict genetic caste determination, resulting in an obligate mutualism between two reproductively isolated lineages. Same-lineage matings produce fertile queens while alternate-lineage matings produce sterile workers. Because new virgin queens mate randomly with multiple males of each lineage type, and both worker and queen phenotypes are required for colony growth and future reproduction, fitness is influenced by the relative frequency of each lineage involved in the mutualistic breeding system. While models based solely on frequency-dependent selection predict the convergence of lineage frequencies towards equal (0.5/0.5), we surveyed the lineage ratios of 49 systems across the range of the mutualism and found that the global lineage frequency differed significantly from equal. Multiple regression analysis of our system survey data revealed that the density and relative frequency of one lineage decreases at lower elevations, while the frequency of the alternate lineage increases with total colony density. While the production of the first worker cohort is largely frequency dependent, relying on the random acquisition of worker-biased sperm stores, subsequent colony growth is independent of lineage frequency. We provide a simulation model showing that a net ecological advantage held by one lineage can lead to the maintenance of stable but asymmetric lineage frequencies. Collectively, these findings suggest that a combination of frequency-dependent and frequency-independent mechanisms can generate many different localized and independently evolving system equilibria. 相似文献
4.
In order to examine the evolution of lineage specific genes, we analyzed intron phase distributions and exon-bordering domains
in primate and rodent specific genes. We found that the expansion of symmetric exon-bordering domains could not explain the
evolution of lineage specific genes. Rather internal intron loss of a domain can partially explain the excess of class 1–1
intron phases in the lineage specific genes. We suggest the event that led to excess of symmetric exons in lineage specific
genes had little bearing on shaping the phenotypes specific to the individual lineage. Instead, Kruppel-associated box (KRAB)
proteins associated with zinc finger C2H2 (zf-C2H2) type are likely to be responsible for the lineage specific function. 相似文献
5.
《Bioscience, biotechnology, and biochemistry》2013,77(3):728-734
Embryonic stem (ES) cells can differentiate into functional hepatic lineage cells, which can potentially be used in biomedicine. To obtain hepatic lineage cells from ES cells, embryoid bodies (EBs) must be formed. In this study, we developed an EB formation system using a spinner flask for mass production of EBs. ES cells were inoculated into the spinner flask, where they formed EBs within 4 d. The EBs were then transferred into an attached culture for hepatic differentiation. To verify the hepatic lineage cells, albumin secretion and hepatic-specific gene expression were examined. We found that EBs formed by either the spinner flask or hanging drops exhibited similar albumin secretion potential and hepatic-specific gene expression. We conclude that the spinner flask method can be used to produce mouse EBs that can be used to mass produce hepatic lineage cells for use in biomedicine. 相似文献
6.
《Biophysical journal》2021,120(19):4193-4201
Rapid advance of experimental techniques provides an unprecedented in-depth view into complex developmental processes. Still, little is known on how the complexity of multicellular organisms evolved by elaborating developmental programs and inventing new cell types. A hurdle to understanding developmental evolution is the difficulty of even describing the intertwined network of spatiotemporal processes underlying the development of complex multicellular organisms. Nonetheless, an overview of developmental trajectories can be obtained from cell type lineage maps. Here, we propose that these lineage maps can also reveal how developmental programs evolve: the modes of evolving new cell types in an organism should be visible in its developmental trajectories and therefore in the geometry of its cell type lineage map. This idea is demonstrated using a parsimonious generative model of developmental programs, which allows us to reliably survey the universe of all possible programs and examine their topological features. We find that, contrary to belief, tree-like lineage maps are rare, and lineage maps of complex multicellular organisms are likely to be directed acyclic graphs in which multiple developmental routes can converge on the same cell type. Although cell type evolution prescribes what developmental programs come into existence, natural selection prunes those programs that produce low-functioning organisms. Our model indicates that additionally, lineage map topologies are correlated with such a functional property: the ability of organisms to regenerate. 相似文献
7.
Yin CH Chen W Hsiao CC Kuo CY Chen CL Wu WT 《Bioscience, biotechnology, and biochemistry》2007,71(3):728-734
Embryonic stem (ES) cells can differentiate into functional hepatic lineage cells, which can potentially be used in biomedicine. To obtain hepatic lineage cells from ES cells, embryoid bodies (EBs) must be formed. In this study, we developed an EB formation system using a spinner flask for mass production of EBs. ES cells were inoculated into the spinner flask, where they formed EBs within 4 d. The EBs were then transferred into an attached culture for hepatic differentiation. To verify the hepatic lineage cells, albumin secretion and hepatic-specific gene expression were examined. We found that EBs formed by either the spinner flask or hanging drops exhibited similar albumin secretion potential and hepatic-specific gene expression. We conclude that the spinner flask method can be used to produce mouse EBs that can be used to mass produce hepatic lineage cells for use in biomedicine. 相似文献
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Ng RK Dean W Dawson C Lucifero D Madeja Z Reik W Hemberger M 《Nature cell biology》2008,10(11):1280-1290
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Mochizuki A 《Journal of theoretical biology》1999,197(2):227-245
Cell lineage of a multicellular organism has been analysed by introducing a genetic or chemical marker that is inherited from a cell to its daughter cells and is detectable even after several cell divisions. To construct a complete cell lineage, all the cells at different developmental stages need to be identified, and then the intracellular marker must be introduced to each cell. In this paper, I study a new method of estimating cell lineage based on distributions of intercellular markers observed at a single stage, which are introduced randomly at earlier stages. Assumptions are: (1) cell lineage is invariant between embryos; (2) a small number of cells are marked in each experiment; and (3) the total number of replicate experiments is sufficiently large. Then we identify the most likely cell lineage pattern (or tree topology) as the one that requires the least marker insertions to be compatible with the observed distributions of cell markers. This method is essentially the same as the principle of persimony widely used for ancestral phylogeny reconstruction in evolutionary biology. When the total number of cells is small, we can generate all the possible cell lineages and calculate the minimum number of marker insertions for each candidate, and then choose the cell lineage that requires the least marker insertions. If the number of cells is large, we can use clustering method in which a pair of cells with the highest correlation in marker labelling are merged sequentially. The efficiency of the clustering method in estimating the correct cell lineage is confirmed by computer simulations. Finally, the clustering method is applied to reconstruct the cell lineage of ascidian from experimental data. 相似文献
10.
Intraspecific phylogeny and lineage group identification based on the prfA virulence gene cluster of Listeria monocytogenes 总被引:2,自引:0,他引:2
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Ward TJ Gorski L Borucki MK Mandrell RE Hutchins J Pupedis K 《Journal of bacteriology》2004,186(15):4994-5002
Listeria monocytogenes is a serious food-borne pathogen that can cause invasive disease in humans and other animals and has been the leading cause of food recalls due to microbiological concerns in recent years. In order to test hypotheses regarding L. monocytogenes lineage composition, evolution, ecology, and taxonomy, a robust intraspecific phylogeny was developed based on prfA virulence gene cluster sequences from 113 L. monocytogenes isolates. The results of the multigene phylogenetic analyses confirm that L. monocytogenes comprises at least three evolutionary lineages, demonstrate that lineages most frequently (lineage 1) and least frequently (lineage 3) associated with human listeriosis are sister-groups, and reveal for the first time that the human epidemic associated serotype 4b is prevalent among strains from lineage 1 and lineage 3. In addition, a PCR-based test for lineage identification was developed and used in a survey of food products demonstrating that the low frequency of association between lineage 3 isolates and human listeriosis cases likely reflects rarity of exposure and not reduced virulence for humans as has been previously suggested. However, prevalence data do suggest lineage 3 isolates may be better adapted to the animal production environment than the food-processing environment. Finally, analyses of haplotype diversity indicate that lineage 1 has experienced a purge of genetic variation that was not observed in the other lineages, suggesting that the three L. monocytogenes lineages may represent distinct species within the framework of the cohesion species concept. 相似文献
11.
Successful maintenance of cellular lineages critically depends on the fate decision dynamics of stem cells (SCs) upon division. There are three possible strategies with respect to SC fate decision symmetry: (a) asymmetric mode, when each and every SC division produces one SC and one non-SC progeny; (b) symmetric mode, when 50% of all divisions produce two SCs and another 50%—two non-SC progeny; (c) mixed mode, when both the asymmetric and two types of symmetric SC divisions co-exist and are partitioned so that long-term net balance of the lineage output stays constant. Theoretically, either of these strategies can achieve lineage homeostasis. However, it remains unclear which strategy(s) are more advantageous and under what specific circumstances, and what minimal control mechanisms are required to operate them. Here we used stochastic modeling to analyze and quantify the ability of different types of divisions to maintain long-term lineage homeostasis, in the context of different control networks. Using the example of a two-component lineage, consisting of SCs and one type of non-SC progeny, we show that its tight homeostatic control is not necessarily associated with purely asymmetric divisions. Through stochastic analysis and simulations we show that asymmetric divisions can either stabilize or destabilize the lineage system, depending on the underlying control network. We further apply our computational model to biological observations in the context of a two-component lineage of mouse epidermis, where autonomous lineage control has been proposed and notable regional differences, in terms of symmetric division ratio, have been noted—higher in thickened epidermis of the paw skin as compared to ear and tail skin. By using our model we propose a possible explanation for the regional differences in epidermal lineage control strategies. We demonstrate how symmetric divisions can work to stabilize paw epidermis lineage, which experiences high level of micro-injuries and a lack of hair follicles as a back-up source of SCs. 相似文献
12.
Ben Wielstra 《Evolution; international journal of organic evolution》2020,74(10):2427-2428
Introgression, gene flow from one population into another, can be asymmetric. Yang et al. suggest that reduction of gene flow in one direction, rather than elevated gene flow in the opposite direction, explains the pattern of asymmetric introgression between two lizard lineages. The authors propose that a dominant male phenotype in one lineage blocks a submissive male phenotype from another lineage in mating with females of the opposite lineage. This case underscores just how capricious introgression can be. 相似文献
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von Boehmer H 《Current biology : CB》2000,10(17):R642-R645
Mechanisms of lineage choice represent a challenging problem in developmental biology. Recent studies have shown that different T-cell receptor signals can affect CD4 or CD8 lineage choice. Thus, all the ingredients for instructive mechanisms of lineage fate are in place but other mechanisms cannot be completely ruled out. 相似文献
15.
Philip Carl Salzman 《American anthropologist》1978,80(1):53-70
Uncritical application of lineage theory can obscure the complex reality of political organization and process in segmentary societies. However, the argument that lineage theory is a folk ideology with no basis in behavioral reality seems unsupportable in the light of comparative and historical evidence which indicates that short-term and long-term territorial stability or instability are operative factors in the symbolic and behavioral significance of lineage organization . [segmentary lineage systems, complementary opposition, ideology, political alliance, ecology] 相似文献
16.
Molecular markers for identified neuroblasts and ganglion mother cells in the Drosophila central nervous system. 总被引:4,自引:0,他引:4
C Q Doe 《Development (Cambridge, England)》1992,116(4):855-863
The first step in generating cellular diversity in the Drosophila central nervous system is the formation of a segmentally reiterated array of neural precursor cells, called neuroblasts. Subsequently, each neuroblast goes through an invariant cell lineage to generate neurons and/or glia. Using molecular lineage markers, I show that (1) each neuroblast forms at a stereotyped time and position; (2) the neuroblast pattern is indistinguishable between thoracic and abdominal segments; (3) the development of individual neuroblasts can be followed throughout early neurogenesis; (4) gene expression in a neuroblast can be reproducibly modulated during its cell lineage; (5) identified ganglion mother cells form at stereotyped times and positions; and (6) the cell lineage of four well-characterized neurons can be traced back to two identified neuroblasts. These results set the stage for investigating neuroblast specification and the mechanisms controlling neuroblast cell lineages. 相似文献
17.
Young HE Duplaa C Romero-Ramos M Chesselet MF Vourc'h P Yost MJ Ericson K Terracio L Asahara T Masuda H Tamura-Ninomiya S Detmer K Bray RA Steele TA Hixson D el-Kalay M Tobin BW Russ RD Horst MN Floyd JA Henson NL Hawkins KC Groom J Parikh A Blake L Bland LJ Thompson AJ Kirincich A Moreau C Hudson J Bowyer FP Lin TJ Black AC 《Cell biochemistry and biophysics》2004,40(1):1-80
Tissue restoration is the process whereby multiple damaged cell types are replaced to restore the histoarchitecture and function
to the tissue. Several theories, have been proposed to explain the phenomenon of tissue restoration in amphibians and in animals
belonging to higher order. These theories include dedifferentiation of damaged tissues, transdifferentiation of lineage-committed
progenitor cells, and activation of reserve, precursor cells. Studies by Young et al. and others demonstrated that connective
tissue compartments throughout postnatal individuals contain reserve precursor cells. Subsequent repetitive single cell-cloning
and cell-sorting studies revealed that these reserve precursor cells consisted of multiple populations of cells, including,
tissue-specific progenitor cells, germ-layer lineage stem cells, and pluripotent stem cells. Tissue-specific progenitor cells
display various capacities for differentiation, ranging from unipotency (forming a single cell type) to multipotency (forming
multiple cell types). However, all progenitor cells demonstrate a finite life span of 50 to 70 population doublings before
programmed cell senescence and cell death occurs. Germ-layer lineage stem cells can form a wider range of cell types than
a progenitor cell. An individual germ-layer lineage stem cell can form all cells types within its respective germ-layer lineage
(i.e., ectoderm, mesoderm, or endoderm). Pluripotent stem cells can form a wider range of cell types than a single germ-layer
lineage stem cell. A single pluripotent stem cell can form cells belonging to all three germ layer lineages. Both germ-layer
lineage stem cells and pluripotent stem cells exhibit extended capabilities for self-renewal, far surpassing the limited life
span of progenitor cells (50–70 population doublings). The authors propose that the activation of quiescent tissue-specific
progenitor cells, germ-layer lineage stem cells, and/or pluripotent stem cells may be a potential explanation, along with
dedifferentiation and transdifferentiation, for the process of tissue restoration. Several model systems are currently being
investigated to determine the possibilities of using these adult quiescent reserve precursor cells for tissue engineering. 相似文献
18.
Meinersmann RJ Phillips RW Wiedmann M Berrang ME 《Applied and environmental microbiology》2004,70(4):2193-2203
In an attempt to develop a method to discriminate among isolates of Listeria monocytogenes, the sequences of all of the annotated genes from the fully sequenced strain L. monocytogenes EGD-e (serotype 1/2a) were compared by BLASTn to a file of the unfinished genomic sequence of L. monocytogenes ATCC 19115 (serotype 4b). Approximately 7% of the matching genes demonstrated 90% or lower identity between the two strains, and the lowest observed identity was 80%. Nine genes (hisJ, cbiE, truB, ribC, comEA, purM, aroE, hisC, and addB) in the 80 to 90% identity group and two genes (gyrB and rnhB) with approximately 97% identity were selected for multilocus sequence analysis in two sets of L. monocytogenes isolates (a 15-strain diversity set and a set of 19 isolates from a single food-processing plant). Based on concatenated sequences, a total of 33 allotypes were differentiated among the 34 isolates tested. Population genetics analyses revealed three lineages of L. monocytogenes that differed in their history of apparent recombination. Lineage I appeared to be completely clonal, whereas representatives of the other lineages demonstrated evidence of horizontal gene transfer and recombination. Although most of the gene sequences for lineage II strains were distinct from those of lineage I, a few strains with the majority of genes characteristic of lineage II had some that were characteristic of lineage I. Genes from lineage III organisms were mostly similar to lineage I genes, with instances of genes appearing to be mosaics with lineage II genes. Even though lineage I and lineage II generally demonstrated very distinct sequences, the sequences for the 11 selected genes demonstrated little discriminatory power within each lineage. In the L. monocytogenes isolate set obtained from one food-processing plant, lineage I and lineage II were found to be almost equally prevalent. While it appears that different lineages of L. monocytogenes can share habitats, they appear to differ in their histories of horizontal gene transfer. 相似文献
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The development of T cells results in a concordance between the specificity of the TCR for MHC class I and class II molecules and the expression of CD8 and CD4 coreceptors. Based on analogy to simple metazoan models of organ development and lineage commitment, we sought to determine whether extracellular signal-related kinase (Erk) mitogen-activated protein (MAP) kinase pathway signaling acts as an inductive signal for the CD4 lineage. Here, we show that, by altering the intracellular signaling involving the Erk/MAP kinase pathway, T cells with specificity for MHC class I can be diverted to express CD4, and, conversely, T cells with specificity for MHC class II can be diverted to express CD8. Furthermore, we find that activation of the src-family tyrosine kinase, p56lck is an upstream mediator of lineage commitment. These results suggest a simple mechanism for lineage commitment in T cell development. 相似文献