International conference on bioinformatics of genome regulation
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Key words: expression profiling, single cell, neural cells The zebrafish neural crest is now an established model for studies of cellular and genetic mechanisms underlying embryonic development in vertebrates. Neural crest (NC) cells are multipotent stem cells that form from the edge of the neural plate, but which delami- nate and then form a great diversity of derivative cell-types. The NC is a major model for understanding stem cell differentiation, in particular how multipotent progenitors generate a balance of different derived cell-types. In this context, we use zebrafish pigment cell de- velopment as our model system, primarily because pigment cells are self-labelling so that simple microscopy allows observation of subtle phenotypic effects in vivo. Furthermore, in contrast to mammals, zebrafish have three NC-derived pigment cell-types – melano- cytes (black), iridophores (silver) and xanthophores (yellow), all of which are thought to share a common cellular origin. We have developed an iterative approach which combines mathematical modelling with in vivo genetic studies to generate and formally assess gene regulatory networks (GRNs) in stem cell development. Following our initial studies of the melanocyte GRN (1), we are now focused on understanding how different pigment cell types can be generated from a common NC precursor. Specifically, we are focus- ing on the shared origin of melanocytes and iridiophores from a shared melanoiridoblast. We are building a quantitative model of the GRN underlying melanocyte and iridophore fate specification. To achieve this goals we have profiled the expression of single cells derived from the NC throughout a time-course of pigment cell development (18 to 72 hpf). For each time point, NC–derived GFP-positive cells from transgenic embryos were individually isolated using FACS; and expression levels for 45 genes (including known core neural crest/pigment cell genes such as mitfa, ltk, sox10, foxd3, tfec) were assessed using nanoString technology. Our ongoing analysis of these data give us a unique view of the diversity and quantitative gene profile of single NC cells freshly ex vivo, allowing unequalled insight into the state of neural crest cells in vivo.. Clustering analysis of the ex- pression profiles identifies cells that show an expression pattern consistent with them be- ing common precursors for both melanocytes and iridophores. Other cell clusters possess characteristics of more multipotent NC cells, including likely common precursors for both pigment cells and other cell types (e.g. glia or enteric neurones). Later in development, we observe cells with profiles consistent with differentiated cell-types e.g. melanocytes or iri- dophores. We are now developing single cell expression profiles for NC of mutants (mitfa, sox10 and ltk) known to affect melanocyte or iridophore fate specification. Likewise, using single cell expression data for parameter fitting, we are now developing a quantitatively accurate mathematical model of the melanoiridoblast GRN. Initially, the parameters are fitted using the wild-type data, and the resultant quantitative model is being used to gener- ate quantitative predictions of the mutant phenotypes. At the end of this process, we expect to have a refined GRN for the pigment cell progenitor and will be able to test the prediction that stochastic variation in gene expression levels could play an essential role in cell fate decision making. 303 THE TENTH INTERNATIONAL CONFERENCE ON BIOINFORMATICS OF GENOME REGULATION AND STRUCTURE\SYSTEMS BIOLOGY MOLECULAR PHYLOGENETIC ANALYSIS OF THE GRASSHOPPERS OF FAMILY ACRIDIDAE BASED ON SEVERAL MITOCHONDRIAL AND NUCLEAR MARKERS I.S. Sukhikh 1 *, A.G. Blinov 1 , A.G. Bugrov 2 1 Institute of Cytology and Genetics SB RAS, Novosibirsk, Russia 2 Institute of Systematics and Ecology of Animals SB RAS, Novosibirsk, Russia * Corresponding author: igor3419@gmail.com Key words: Acrididae, phylogeny, mitochondrial DNA, ribosomal DNA Motivation and Aim: Acrididae is the biggest family of Acridoidea superfamily, includ- ing from 25 to 34 subfamilies according to different classifications, and several genus that assigned to no family. It is worth noting that the few subfamilies consists of small number of genus and species. For a long time, taxonomy, the renovation of phylogenetic relationships and understanding of the evolution of Acrididae family were based mainly on comparison analysis of key morphological structures of recent and fossil species. However, on subfamily level, the problems of convergence and parallelism are rising up for these insects. One of the most effective methods of establishing phylogenetic rela- tionships is the analysis of various DNA markers. Methods and Algorithms: In present work, we conducted molecular phylogenetic analy- sis of complete mitochondrial sequences, mitochondrial (COI, COII, CytB) and nuclear (ITS2, 28S rRNA) markers of more than 220 species of Acrididae family from 26 sub- families, extracted from these insects experimentally and obtained from NCBI data- base. Phylogenetic trees for different combinations of these markers were obtained using maximize likelihood and Bayesian methods. Results: As the result of the work done, we found out that all of locusts’ species under discussion grouping up into 13 phylogenetic clusters, and phylogenetic relationships between them were established. Five out of 26 subfamilies (Acridinae, Oedipodinae, Gomphocerinae, Oxyinae and Catantopinae) found to be polyphyletic in present study, which point out the shortcoming of current taxonomy. The data obtained allowed us to clarify the classification of Acrididae species. Availability: All DNA marker sequences will be in a free access in the NCBI database. 304 THE TENTH INTERNATIONAL CONFERENCE ON BIOINFORMATICS OF GENOME REGULATION AND STRUCTURE\SYSTEMS BIOLOGY COMPREHENSIVE ANALYSIS OF DRAFT GENOMES OF TWO CLOSELY RELATED PSEUDOMONAS SYRINGAE PHYLOGROUP 2B STRAINS INFECTING MONO- AND DICOTYLEDON HOST PLANTS R.I. Sultanov 1, 2 *, G.P. Arapidi 1, 2 , S.V. Vinogradova 3 , V.M. Govorun 1, 2, 4 , D.G. Luster 5 , A.N. Ignatov 6 1 Moscow Institute of Physics and Technology (State University), Moscow, Russia 2 Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, the Russian Academy of Sciences, Moscow, Russia 3 Research Center of Biotechnology, Moscow, Russia 4 SRCC of Physical-Chemical Medicine, Moscow, Russia 5 USDA-ARS Foreign Disease - Weed Science Research Unit, Ft. Detrick, USA 6 R&D Center “Phytoengineering” LLS, Moscow region, Russia * Corresponding author: rhenium112@gmail.com Key words: Pseudomonas syringae, dicots, monocots, pan-genome, core genome, T3SS, virulence factors Motivation and Aim: In recent years, the damage caused by bacterial pathogens to major crops has been increasing worldwide. Pseudomonas syringae is a widespread bacterial species that infects almost all major crops. Different P. syringae strains use a wide range of biochemical mechanisms, including phytotoxins and effectors of the type III and type IV secretion systems, which determine the specific nature of the pathogen virulence. Methods and Algorithms: The genomes of Pseudomonas syringae strains 2507 (wheat) and 1845 (sunflower) isolated on the territory of the Russian Federation were determined by pyrosequencing and compared with previously published sequences of 18 genomes of the strains belonging to the same phylogroup and affecting dicots and monocots. We analyzed seven informative genes used in MLST genotyping of P. syringae, calculated the average nucleotide identity (ANI), and examined the compositions of the type III secretion system (T3SS) effectors and of the elements of insertion sequences (IS). Results: We found that strains 2507 and 1845 and strains SM and B64 form a subgroup that is stable among the other strains of phylogroup 2b. The analysis of the genome of strain 1845 indicated the recent loss of several genetic elements (the cluster of genes responsible for the synthesis of syringolin and the prophage cluster) that are present in strains 2507, B64, and SM. We found three genes (YP_234264.1, YP_234265.1, and YP_237386.1), the acquisition of which by strain 1845 could lead to the change in its host class. Conclusion: The results obtained by comparing the strain 1845 genome with the ge- nomes of bacteria infecting monocots can help to identify the genes that define specific nature of the virulence of P. syringae strains. Availability: The genomes of P. syringae strains 1845 and 2507 will be available soon at NCBI. 305 THE TENTH INTERNATIONAL CONFERENCE ON BIOINFORMATICS OF GENOME REGULATION AND STRUCTURE\SYSTEMS BIOLOGY 1 Given this Fisher [1], the author of the definition, also proposed the geometric interpretation of the ad- aptation in which, factually, rediscovered the V.Kovalevsky inadaptation and anadaptation terms indistin- guishabled through ω and predicted the necessity for the formation of Eldrege and Gould’s stasis. 2 Disagreements between temps of invasion, adaptation and evolution are a quick transition from slow to rapid invasion in new econiche/biotope and vice versa (i), the relative irrelevance of a successful invasion of a new econiche to preadaptation to that one (ii) and discordance between evolutionary and adaptation rates of small populations during invasion (iii) [2]. 3 In situ assessment used into the habitat by the organism-invader with receptor repertoire that can evaluate aboriginal signals [3]. Without the repertoire an organism can assess own chances based on the own stress- reaction developing during invasion in novelty [2]. 4 R – resources to target action Z; s – environment; Q – operator, that is, feature for the R→Z transition built on the genome information I; p, P – probabilities of transition in given s: p – randomly, P – with Q(I); w – transition by-products [4]. 5 Or preventive adaptation that stabilizes the area and eventually the population size (random expansion also requires a large population). 6 For example, in course of stress-reaction tiredness resulting an interference of mobilized resources warns about the danger of resource depletion long before its exhaustion [2]. ADAPTATION AND BIOLOGICAL TIME V.V. Suslov Institute of Cytology and Genetics SB RAS, Novosibirsk, Russia * Corresponding author: valya@bionet.nsc.ru Key words: information, invasion, evolution, adaptation Motivation. Operationalize simplicity is an indisputable advantage of the classical defini- tion any adaptation in terms of fitness ω. But the definition is not universa l , particularly, via ω cannot explain the Osborne effect 2 requiring assessment of the own adaptation not only a posteriori (i), but also in situ 3 (ii). Both i (by I preservation which due to the information caducity requires both I maintaining and I replication) and ii (by R/w) allows the adaptation formalism [R,s] Q(I)/(p,P)→[Z,w] 4 [4]. Results. If true, but not used (unnecessary) information degraded [4] and an increasing of ω requires stability of s at least during reproduction period, the increasing of ω under s=const (ω(s=const)>const) will lead to a priory incomplete preservation of I and selection in favor of a temperate noise, i.e. the I somehow associated with a relatively large number of Q regard- less of ω (ω(s=const)≥const) and I’s verity. Hence, even I maintaining requires expansion, for which remains the only Gause’s mechanism easily blocked under ω(s)>const by density- dependent regulation [2]. Adaptation in terms of ω and adaptation in terms of permanent expansion are complementary, but in situ assessment can be formalized as (time for R→Z transition)/(effective time which has an organism under the s). Both biotimes organism can estimated due to interference of resources and by-products. Autoreplicator has not the simple preemptive reflection because the selection in favor of accuracy and speed of I replication eliminates interference organizing replication by linearly (genomes) or conformational (pri- ons) matrix types, by the way, decreasing possibility to use the R/w in situ assessment. Acknowledgements: budget 0324-2015-0003; RSF 14-24-00123; RFBR 14-04-00485. References: 1. R. Fisher (1930), The Genetical Theory of Natural Selection. Oxford Univ. Press: 318. 2. V.V. Suslov (2014), BGRS\SB-2014: 180-184. 3. V.S. Fridman, G.S. Eremkin (2008), Urbanization of “Wild” Avian Species in Evolving Urban Land- scapes. М. MSU: 139 (in Russ.) 4. V.I. Korogodin, V.L. Korogodina (2012), Phenomenon of Life. V.2. М. Nauka: 173-338. 306 THE TENTH INTERNATIONAL CONFERENCE ON BIOINFORMATICS OF GENOME REGULATION AND STRUCTURE\SYSTEMS BIOLOGY TATA-BOX AND GENE EXPRESSION NORM OF REACTION V.V. Suslov*, M.P. Ponomarenko, D.A. Rasskazov Institute of Cytology and Genetics SB RAS, Novosibirsk, Russia * Corresponding author: valya@bionet.nsc.ru Key words: ТАТA-box, norm of reaction, gene expression Motivation: In 2014, we demonstrated that the TATA-box is a molecular regulator of norm of reaction (NR). It contributes to the variability of the most common property of gene expression, its transcriptional level [1]. However, the contribution used only mechanism of the regulation based on the model of Blake et al. [3] where TBP/TATA affinity can influence variability of the gene transcriptional level through change of the ratio of initiation/preinitiation promoter stages. NR is not limited to the transcriptional level and can include many features (specificity by tissue, transcriptional factor (TF), etc.) and mechanisms of the own alteration. This study is conducted to find them. Methods. TBP/TATA affinity (−ln[K D , TATA (S)]) of the naturally TATA-boxes with flanks and composite elements (CEs) where one of the flanks shared between the TATA-box and another binding site were in silico investigated by the Web-service SNP_TATA_ Comparator (http://beehive.bionet.nsc.ru) which using the equilibrium equation for the four subsequent steps of TBP/TATA-box binding [2]. Results: 1) To start the HERV-H virus transcription its GC/GT-box must bind cellular transcription factor SP1. Its protected area overlaps half of the TATA-consensus. It was shown that mutations in free flank as one in protected area infringed (−ln[K D , TATA (S)]). If mutations in protected area violated SP1-binding, then they align the levels of Sp1 and Sp3 transcription. If mutations violate the (−ln[K D , TATA (S)]) only, they decreased both Sp1 and Sp3 transcription levels but retained the difference between them. These data suggest that in the CE the TATA-box limits the overall level of transcription, within which realiz- es TF-specific levels. 2) It was shown that in a similar CEs the (−ln[K D , TATA (S)]) can limit overall level of transcription within which another TFs realized different tissue-specific transcriptional patterns. 3) The complication of the previous case was found. That is two closely spaced or overlapping TATA-boxes. The competition between them affects the specific regulation of the gene expression. (Experiments where the (−ln[K D , TATA (S)]) can influence to the probability of polymerase usage (polII or polIII) described in literature). 4) Model [3] is based on the additive multi-step process of the transcription activation. The (−ln[K D , TATA (S)]) can influence to the any step but the only step is the actual initia- tion. Hence, preinitiation promoter stages can be replaced by the reinitiating stage or major/minor transcripts ratio. Both cases were found. Thus, TATA-box can affect to the transcriptional NR in various ways. This confirms earlier suggestion about TATA-box as an element, encoding gene NR. The question about the element in the literature was not compromised earlier. Acknowledgements: budget 0324-2015-0003; RSF 14-24-00123; RFBR 14-04-00485. References: 1. P.M. Ponomarenko et al. (2014), Rus. Journ. of Gen.: Appl. Res., 18: 1219-1230. 2. P.M. Ponomarenko et al. (2009), Mol. Biol. (Mosk), 43(3): 512-520. 3. W.J. Blake et al. (2006), Mol. Cell., 24(6): 853–865. 307 THE TENTH INTERNATIONAL CONFERENCE ON BIOINFORMATICS OF GENOME REGULATION AND STRUCTURE\SYSTEMS BIOLOGY VAVILOV’S HOMOLOGOUS SERIES AS EVOLUTIONARY FORCE V.V. Suslov*, M.P. Ponomarenko, D.A. Rasskazov Institute of Cytology and Genetics SB RAS, Novosibirsk, Russia * Corresponding author: valya@bionet.nsc.ru Key words: Vavilov’s homologous series, evolution, adaptation, coadaptive substitutions Motivation. TBP/TATA affinity (−ln[K D , TATA (S)]) of the naturally TATA-boxes with flanks and composite elements (CEs) where one of the flanks shared between the TATA-box and another binding site (BS) was in silico investigated by the Web-service SNP_TATA_Comparator 1 (http:// beehive.bionet.nsc.ru). Results. 1) For TATA-boxes of the polII-transcribed genes similar −ln[K D , TATA (S)] obtained with various combinations of substitutions in the TATA-consensus and flanks. 2) On the other hand, if the TATA-consensuses and their sequence analogs in TATA-less promoters have not changed, mutations in flanks have shifted the −ln[K D , TATA (S)] of TATA-promoters to the one of TATA- less promoters and vice versa. 3) For CEs, the mutational or phylogenetical changing of the −ln[K D , TATA (S)] significantly negative correlated with the changes in affinity of another BS to its transcriptional factor (TF). 4) For promoters of the polIII-transcribed genes TATA-consensus with flanks formed CEs with sites of TAFs 2 but SNP_TATA_Comparator allows us to distinguish the contribution of −ln[K D , TATA (S)] to transcription, even in cases that are not distinguishable by the level of gene expression, but distinguishable in nucleotide context of TATA-boxes and flanks. That is, between the TATA consensus and flanks, as well as between the TATA-box and BS in CE there is a mutual compensation for the function. The same function 3 can obtain by different combinations of substitutions, i.e. these combinations are Vavilov’s homologous series (HS). But classic – Vavilov or Sobolev’s – HS consist of several combinations of features where elimination some feature cannot break the combination’s function 4 [2]. In our case, it is impossible. Func- tional overlap is too great, and evolution of the combination is similar to the protein’s coadaptive substitutions, i.e. it can go in a stable but not favorable environment depending on the mutability and degree of functional overlap. HS may be the trend of autoadaptation. Generalization to other cases of HS with high functional overlapping 5 gives the rule of divergence/convergence HS 6 . Acknowledgements: budget 0324-2015-0003; RSF 14-24-00123; RFBR 14-04-00485. References: 1. P.M. Ponomarenko et al. (2009), Mol. Biol. (Mosk), 43(3): 512-520. 2. N.I. Vavilov (1922), J. Genet., 12(1): 47-89 . 1 Which using the equilibrium equation for the four subsequent steps of TBP/TATA-box binding [1]. 2 TBP-associated factors. 3 In our case it is −ln[K D , TATA (S)], or level, or tissue specificity of gene expression. 4 As a rule, such features are in the right – the variable – part of the Vavilov’s radical. E.g. awnless, liguleless cereals [2]. 5 I.e. Gilyarov-Simpson cycle, Abel’s crossing of specializations, Krenke’s HS or interim case of the superblock formation, where a selection that favors the simultaneous gene network regulation by several TFs may lead to a TFs competition for gene network’s space by virtue of its BS formation. The fewer BSs, the higher the probability of TF’s elimination or its specialization in time, tissue etc. 6 The more functional overlap of the features in combination, the higher the probability of HS divergence - the loss of ancestral similarity in a series of combinations (i). The more traits in combination, assuming its functional overlap, the higher the probability of functional suppression and HS divergence. The longer the HS diverge, the more likely the loss of any of the traits (ii). Ultimately, the depletion of HS may lead to its convergence or in case of loss of functional overlap – its stabilization to classic HS (iii). 308 THE TENTH INTERNATIONAL CONFERENCE ON BIOINFORMATICS OF GENOME REGULATION AND STRUCTURE\SYSTEMS BIOLOGY IDENTIFICATION OF PATHWAYS ASSOCIATED WITH CELL DEATH IN THE CORTEX OF OXYS RATS AS THE SIGNS OF ALZHEIMER’S DISEASE DEVELOP G.K. Suvorov*, D.V. Telegina, E.A. Rudnitskaya, N.A. Stefanova, N.G. Kolosova Institute of Cytology and Genetics SB RAS, Novosibirsk, Russia * Corresponding author: augustocash@gmail.com Download 3.91 Kb. Do'stlaringiz bilan baham: |
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