The Experts below are selected from a list of 27051 Experts worldwide ranked by ideXlab platform
Jeremy A. Lynch - One of the best experts on this subject based on the ideXlab platform.
-
patterning the dorsal ventral axis of the wasp nasonia vitripennis
2013Co-Authors: Thomas Buchta, Jeremy A. Lynch, Orhan Özüak, Siegfried Roth, Dominik StappertAbstract:Regulatory Networks composed of interacting genes are responsible for pattern formation and cell type specification in a wide variety of developmental contexts. Evolution must act on these regulatory Networks in order to change the proportions, distribution, and characteristics of specified cells. Thus, understanding how these Networks operate in homologous systems across multiple levels of phylogenetic divergence is critical for understanding the evolution of developmental systems. Among the most thoroughly characterized regulatory Networks is the dorsal-ventral patterning system of the fly Drosophila melanogaster. Due to the thorough understanding of this system, it is an ideal starting point for comparative analyses. Here we report an analysis of the DV patterning system of the wasp, Nasonia vitripennis. This wasp undergoes a mode of long germ embryogenesis that is superficially nearly identical to that of Drosophila, but one that was likely independently derived. We have found that while the expression of genes just prior to the onset of gastrulation is almost identical in Nasonia and Drosophila, both the Upstream Network responsible for generating this pattern, and the downstream morphogenetic movements that it sets in motion, are significantly diverged. From this we conclude that many Network structures are available to evolution to achieve particular developmental ends.
-
The Phylogenetic Origin of oskar Coincided with the Origin of Maternally Provisioned Germ Plasm and Pole Cells at the Base of the Holometabola
2013Co-Authors: Jeremy A. Lynch, Orhan Özüak, Abderrahman Khila, Ehab Abouheif, Claude DesplanAbstract:The establishment of the germline is a critical, yet surprisingly evolutionarily labile, event in the development of sexually reproducing animals. In the fly Drosophila, germ cells acquire their fate early during development through the inheritance of the germ plasm, a specialized maternal cytoplasm localized at the posterior pole of the oocyte. The gene oskar (osk) is both necessary and sufficient for assembling this substance. Both maternal germ plasm and oskar are evolutionary novelties within the insects, as the germline is specified by zygotic induction in basally branching insects, and osk has until now only been detected in dipterans. In order to understand the origin of these evolutionary novelties, we used comparative genomics, parental RNAi, and gene expression analyses in multiple insect species. We have found that the origin of osk and its role in specifying the germline coincided with the innovation of maternal germ plasm and pole cells at the base of the holometabolous insects and that losses of osk are correlated with changes in germline determination strategies within the Holometabola. Our results indicate that the invention of the novel gene osk was a key innovation that allowed the transition from the ancestral late zygotic mode of germline induction to a maternally controlled establishment of the germline found in many holometabolous insect species. We propose that the ancestral role of osk was to connect an Upstream Network ancestrally involved in mRNA localization and translational control to a downstream regulatory Network ancestrally involve
-
The phylogenetic origin of oskar coincided with the origin of maternally provisioned germ plasm and pole cells at the base of the Holometabola.
2011Co-Authors: Jeremy A. Lynch, Orhan Özüak, Abderrahman Khila, Ehab Abouheif, Claude Desplan, Siegfried RothAbstract:The establishment of the germline is a critical, yet surprisingly evolutionarily labile, event in the development of sexually reproducing animals. In the fly Drosophila, germ cells acquire their fate early during development through the inheritance of the germ plasm, a specialized maternal cytoplasm localized at the posterior pole of the oocyte. The gene oskar (osk) is both necessary and sufficient for assembling this substance. Both maternal germ plasm and oskar are evolutionary novelties within the insects, as the germline is specified by zygotic induction in basally branching insects, and osk has until now only been detected in dipterans. In order to understand the origin of these evolutionary novelties, we used comparative genomics, parental RNAi, and gene expression analyses in multiple insect species. We have found that the origin of osk and its role in specifying the germline coincided with the innovation of maternal germ plasm and pole cells at the base of the holometabolous insects and that losses of osk are correlated with changes in germline determination strategies within the Holometabola. Our results indicate that the invention of the novel gene osk was a key innovation that allowed the transition from the ancestral late zygotic mode of germline induction to a maternally controlled establishment of the germline found in many holometabolous insect species. We propose that the ancestral role of osk was to connect an Upstream Network ancestrally involved in mRNA localization and translational control to a downstream regulatory Network ancestrally involved in executing the germ cell program.
Siegfried Roth - One of the best experts on this subject based on the ideXlab platform.
-
patterning the dorsal ventral axis of the wasp nasonia vitripennis
2013Co-Authors: Thomas Buchta, Jeremy A. Lynch, Orhan Özüak, Siegfried Roth, Dominik StappertAbstract:Regulatory Networks composed of interacting genes are responsible for pattern formation and cell type specification in a wide variety of developmental contexts. Evolution must act on these regulatory Networks in order to change the proportions, distribution, and characteristics of specified cells. Thus, understanding how these Networks operate in homologous systems across multiple levels of phylogenetic divergence is critical for understanding the evolution of developmental systems. Among the most thoroughly characterized regulatory Networks is the dorsal-ventral patterning system of the fly Drosophila melanogaster. Due to the thorough understanding of this system, it is an ideal starting point for comparative analyses. Here we report an analysis of the DV patterning system of the wasp, Nasonia vitripennis. This wasp undergoes a mode of long germ embryogenesis that is superficially nearly identical to that of Drosophila, but one that was likely independently derived. We have found that while the expression of genes just prior to the onset of gastrulation is almost identical in Nasonia and Drosophila, both the Upstream Network responsible for generating this pattern, and the downstream morphogenetic movements that it sets in motion, are significantly diverged. From this we conclude that many Network structures are available to evolution to achieve particular developmental ends.
-
The phylogenetic origin of oskar coincided with the origin of maternally provisioned germ plasm and pole cells at the base of the Holometabola.
2011Co-Authors: Jeremy A. Lynch, Orhan Özüak, Abderrahman Khila, Ehab Abouheif, Claude Desplan, Siegfried RothAbstract:The establishment of the germline is a critical, yet surprisingly evolutionarily labile, event in the development of sexually reproducing animals. In the fly Drosophila, germ cells acquire their fate early during development through the inheritance of the germ plasm, a specialized maternal cytoplasm localized at the posterior pole of the oocyte. The gene oskar (osk) is both necessary and sufficient for assembling this substance. Both maternal germ plasm and oskar are evolutionary novelties within the insects, as the germline is specified by zygotic induction in basally branching insects, and osk has until now only been detected in dipterans. In order to understand the origin of these evolutionary novelties, we used comparative genomics, parental RNAi, and gene expression analyses in multiple insect species. We have found that the origin of osk and its role in specifying the germline coincided with the innovation of maternal germ plasm and pole cells at the base of the holometabolous insects and that losses of osk are correlated with changes in germline determination strategies within the Holometabola. Our results indicate that the invention of the novel gene osk was a key innovation that allowed the transition from the ancestral late zygotic mode of germline induction to a maternally controlled establishment of the germline found in many holometabolous insect species. We propose that the ancestral role of osk was to connect an Upstream Network ancestrally involved in mRNA localization and translational control to a downstream regulatory Network ancestrally involved in executing the germ cell program.
Orhan Özüak - One of the best experts on this subject based on the ideXlab platform.
-
patterning the dorsal ventral axis of the wasp nasonia vitripennis
2013Co-Authors: Thomas Buchta, Jeremy A. Lynch, Orhan Özüak, Siegfried Roth, Dominik StappertAbstract:Regulatory Networks composed of interacting genes are responsible for pattern formation and cell type specification in a wide variety of developmental contexts. Evolution must act on these regulatory Networks in order to change the proportions, distribution, and characteristics of specified cells. Thus, understanding how these Networks operate in homologous systems across multiple levels of phylogenetic divergence is critical for understanding the evolution of developmental systems. Among the most thoroughly characterized regulatory Networks is the dorsal-ventral patterning system of the fly Drosophila melanogaster. Due to the thorough understanding of this system, it is an ideal starting point for comparative analyses. Here we report an analysis of the DV patterning system of the wasp, Nasonia vitripennis. This wasp undergoes a mode of long germ embryogenesis that is superficially nearly identical to that of Drosophila, but one that was likely independently derived. We have found that while the expression of genes just prior to the onset of gastrulation is almost identical in Nasonia and Drosophila, both the Upstream Network responsible for generating this pattern, and the downstream morphogenetic movements that it sets in motion, are significantly diverged. From this we conclude that many Network structures are available to evolution to achieve particular developmental ends.
-
The Phylogenetic Origin of oskar Coincided with the Origin of Maternally Provisioned Germ Plasm and Pole Cells at the Base of the Holometabola
2013Co-Authors: Jeremy A. Lynch, Orhan Özüak, Abderrahman Khila, Ehab Abouheif, Claude DesplanAbstract:The establishment of the germline is a critical, yet surprisingly evolutionarily labile, event in the development of sexually reproducing animals. In the fly Drosophila, germ cells acquire their fate early during development through the inheritance of the germ plasm, a specialized maternal cytoplasm localized at the posterior pole of the oocyte. The gene oskar (osk) is both necessary and sufficient for assembling this substance. Both maternal germ plasm and oskar are evolutionary novelties within the insects, as the germline is specified by zygotic induction in basally branching insects, and osk has until now only been detected in dipterans. In order to understand the origin of these evolutionary novelties, we used comparative genomics, parental RNAi, and gene expression analyses in multiple insect species. We have found that the origin of osk and its role in specifying the germline coincided with the innovation of maternal germ plasm and pole cells at the base of the holometabolous insects and that losses of osk are correlated with changes in germline determination strategies within the Holometabola. Our results indicate that the invention of the novel gene osk was a key innovation that allowed the transition from the ancestral late zygotic mode of germline induction to a maternally controlled establishment of the germline found in many holometabolous insect species. We propose that the ancestral role of osk was to connect an Upstream Network ancestrally involved in mRNA localization and translational control to a downstream regulatory Network ancestrally involve
-
The phylogenetic origin of oskar coincided with the origin of maternally provisioned germ plasm and pole cells at the base of the Holometabola.
2011Co-Authors: Jeremy A. Lynch, Orhan Özüak, Abderrahman Khila, Ehab Abouheif, Claude Desplan, Siegfried RothAbstract:The establishment of the germline is a critical, yet surprisingly evolutionarily labile, event in the development of sexually reproducing animals. In the fly Drosophila, germ cells acquire their fate early during development through the inheritance of the germ plasm, a specialized maternal cytoplasm localized at the posterior pole of the oocyte. The gene oskar (osk) is both necessary and sufficient for assembling this substance. Both maternal germ plasm and oskar are evolutionary novelties within the insects, as the germline is specified by zygotic induction in basally branching insects, and osk has until now only been detected in dipterans. In order to understand the origin of these evolutionary novelties, we used comparative genomics, parental RNAi, and gene expression analyses in multiple insect species. We have found that the origin of osk and its role in specifying the germline coincided with the innovation of maternal germ plasm and pole cells at the base of the holometabolous insects and that losses of osk are correlated with changes in germline determination strategies within the Holometabola. Our results indicate that the invention of the novel gene osk was a key innovation that allowed the transition from the ancestral late zygotic mode of germline induction to a maternally controlled establishment of the germline found in many holometabolous insect species. We propose that the ancestral role of osk was to connect an Upstream Network ancestrally involved in mRNA localization and translational control to a downstream regulatory Network ancestrally involved in executing the germ cell program.
Edwin Wang - One of the best experts on this subject based on the ideXlab platform.
-
principles of microrna regulation of a human cellular signaling Network
2006Co-Authors: Qinghua Cui, Enrico O Purisima, Edwin WangAbstract:MicroRNAs (miRNAs) are endogenous 22-nucleotide RNAs, which suppress gene expression by selectively binding to the 3-noncoding region of specific message RNAs through base-pairing. Given the diversity and abundance of miRNA targets, miRNAs appear to functionally interact with various components of many cellular Networks. By analyzing the interactions between miRNAs and a human cellular signaling Network, we found that miRNAs predominantly target positive regulatory motifs, highly connected scaffolds and most downstream Network components such as signaling transcription factors, but less frequently target negative regulatory motifs, common components of basic cellular machines and most Upstream Network components such as ligands. In addition, when an adaptor has potential to recruit more downstream components, these components are more frequently targeted by miRNAs. This work uncovers the principles of miRNA regulation of signal transduction Networks and implies a potential function of miRNAs for facilitating robust transitions of cellular response to extracellular signals and maintaining cellular homeostasis.
-
principles of microrna regulation of a human cellular signaling Network
2006Co-Authors: Zhenbao Yu, Enrico O Purisima, Edwin WangAbstract:MicroRNAs (miRNAs) are endogenous ∼22-nucleotide RNAs, which suppress gene expression by selectively binding to the 3′-noncoding region of specific messenger RNAs through base-pairing. Given the diversity and abundance of miRNA targets, miRNAs appear to functionally interact with various components of many cellular Networks. By analyzing the interactions between miRNAs and a human cellular signaling Network, we found that miRNAs predominantly target positive regulatory motifs, highly connected scaffolds and most downstream Network components such as signaling transcription factors, but less frequently target negative regulatory motifs, common components of basic cellular machines and most Upstream Network components such as ligands. In addition, when an adaptor has potential to recruit more downstream components, these components are more frequently targeted by miRNAs. This work uncovers the principles of miRNA regulation of signal transduction Networks and implies a potential function of miRNAs for facilitating robust transitions of cellular response to extracellular signals and maintaining cellular homeostasis.
Thomas Buchta - One of the best experts on this subject based on the ideXlab platform.
-
patterning the dorsal ventral axis of the wasp nasonia vitripennis
2013Co-Authors: Thomas Buchta, Jeremy A. Lynch, Orhan Özüak, Siegfried Roth, Dominik StappertAbstract:Regulatory Networks composed of interacting genes are responsible for pattern formation and cell type specification in a wide variety of developmental contexts. Evolution must act on these regulatory Networks in order to change the proportions, distribution, and characteristics of specified cells. Thus, understanding how these Networks operate in homologous systems across multiple levels of phylogenetic divergence is critical for understanding the evolution of developmental systems. Among the most thoroughly characterized regulatory Networks is the dorsal-ventral patterning system of the fly Drosophila melanogaster. Due to the thorough understanding of this system, it is an ideal starting point for comparative analyses. Here we report an analysis of the DV patterning system of the wasp, Nasonia vitripennis. This wasp undergoes a mode of long germ embryogenesis that is superficially nearly identical to that of Drosophila, but one that was likely independently derived. We have found that while the expression of genes just prior to the onset of gastrulation is almost identical in Nasonia and Drosophila, both the Upstream Network responsible for generating this pattern, and the downstream morphogenetic movements that it sets in motion, are significantly diverged. From this we conclude that many Network structures are available to evolution to achieve particular developmental ends.
