The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform
Benjamin Peret - One of the best experts on this subject based on the ideXlab platform.
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Anatomical and hormonal description of rootlet Primordium development along white lupin cluster root
Physiologia Plantarum, 2019Co-Authors: Cecilia Gallardo, Barbara Hufnagel, Célia Casset, Carine Alcon, Fanny Garcia, Fanchon Divol, Laurence Marquès, Patrick Doumas, Benjamin PeretAbstract:Cluster root (CR) is one of the most spectacular plant developmental adaptations to hostile environment. It can be found in a few species from a dozen botanical families, including white lupin (Lupinus albus) in the Fabaceae family. These amazing structures are produced in phosphate-deprived conditions and are made of hundreds of short roots also known as rootlets. White lupin is the only crop bearing CRs and is considered as the model species for CR studies. However, little information is available on CRs atypical development, including the molecular events that trigger their formation. To provide insights on CR formation, we performed an anatomical and cellular description of rootlet development in white lupin. Starting with a classic histological approach, we described rootlet Primordium development and defined 8 developmental stages from rootlet initiation to their emergence. Due to the major role of hormones in the developmental program of root system, we next focussed on auxin-related mechanisms. We observed the establishment of an auxin maximum through rootlet development in transgenic roots expressing the DR5:GUS auxin reporter. Expression analysis of the main auxin related genes (TIR, ARF, AUX/IAA…) during a detailed time course revealed specific expression associated with the formation of the rootlet Primordium. We showed that LaTIR1b [TRANSPORT INHIBITOR RESPONSE 1b] is expressed during rootlet Primordium formation and that LaARF5 [AUXIN RESPONSE FACTOR 5] is expressed in the vasculature but absent in the Primordium itself. Altogether, our results describe the very early cellular events leading to CR formation and reveal some of the auxin-related mechanisms.
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Anatomical and hormonal description of rootlet Primordium development along white lupin cluster root.
Physiologia plantarum, 2018Co-Authors: Cecilia Gallardo, Barbara Hufnagel, Célia Casset, Carine Alcon, Fanny Garcia, Fanchon Divol, Laurence Marquès, Patrick Doumas, Benjamin PeretAbstract:Cluster root (CR) is one of the most spectacular plant developmental adaptations to hostile environment. It can be found in a few species from a dozen botanical families, including white lupin (Lupinus albus) in the Fabaceae family. These amazing structures are produced in phosphate-deprived conditions and are made of hundreds of short roots also known as rootlets. White lupin is the only crop bearing CRs and is considered as the model species for CR studies. However, little information is available on CRs atypical development, including the molecular events that trigger their formation. To provide insights on CR formation, we performed an anatomical and cellular description of rootlet development in white lupin. Starting with a classic histological approach, we described rootlet Primordium development and defined eight developmental stages from rootlet initiation to their emergence. Due to the major role of hormones in the developmental program of root system, we next focussed on auxin-related mechanisms. We observed the establishment of an auxin maximum through rootlet development in transgenic roots expressing the DR5:GUS auxin reporter. Expression analysis of the main auxin-related genes [TIR, Auxin Response Factor (ARF) and AUX/IAA] during a detailed time course revealed specific expression associated with the formation of the rootlet Primordium. We showed that L. albus TRANSPORT INHIBITOR RESPONSE 1b is expressed during rootlet Primordium formation and that L. albus AUXIN RESPONSE FACTOR 5 is expressed in the vasculature but absent in the Primordium itself. Altogether, our results describe the very early cellular events leading to CR formation and reveal some of the auxin-related mechanisms.
Ajay B. Chitnis - One of the best experts on this subject based on the ideXlab platform.
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Zebrafish Posterior Lateral Line Primordium migration requires interactions between a superficial sheath of motile cells and the skin.
eLife, 2020Co-Authors: Damian Dalle Nogare, Naveen Natesh, Harshad D. Vishwasrao, Hari Shroff, Ajay B. ChitnisAbstract:The Zebrafish Posterior Lateral Line Primordium migrates in a channel between the skin and somites. Its migration depends on the coordinated movement of its mesenchymal-like leading cells and trailing cells, which form epithelial rosettes, or protoneuromasts. We describe a superficial population of flat Primordium cells that wrap around deeper epithelialized cells and extend polarized lamellipodia to migrate apposed to the overlying skin. Polarization of lamellipodia extended by both superficial and deeper protoneuromast-forming cells depends on Fgf signaling. Removal of the overlying skin has similar effects on superficial and deep cells: lamellipodia are lost, blebs appear instead, and collective migration fails. When skinned embryos are embedded in Matrigel, basal and superficial lamellipodia are recovered; however, only the directionality of basal protrusions is recovered, and migration is not rescued. These observations support a key role played by superficial Primordium cells and the skin in directed migration of the Posterior Lateral Line Primordium.
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netlogo agent based models as tools for understanding the self organization of cell fate morphogenesis and collective migration of the zebrafish posterior lateral line Primordium
Seminars in Cell & Developmental Biology, 2020Co-Authors: Damian Dalle Nogare, Ajay B. ChitnisAbstract:Abstract Interactions between Primordium cells and their environment determines the self-organization of the zebrafish posterior Lateral Line Primordium as it migrates under the skin from the ear to the tip of the tail forming and depositing neuromasts to spearhead formation of the posterior Lateral Line sensory system. In this review we describe how the NetLogo agent-based programming environment has been used in our lab to visualize and explore how self-generated chemokine gradients determine collective migration, how the dynamics of Wnt signaling can be used to predict patterns of neuromast deposition, and how previously defined interactions between Wnt and Fgf signaling systems have the potential to determine the periodic formation of center-biased Fgf signaling centers in the wake of a shrinking Wnt system. We also describe how NetLogo was used as a database for storing and visualizing the results of in toto lineage analysis of all cells in the migrating Primordium. Together, the models illustrate how this programming environment can be used in diverse ways to integrate what has been learnt from biological experiments about the nature of interactions between cells and their environment, and explore how these interactions could potentially determine emergent patterns of cell fate specification, morphogenesis and collective migration of the zebrafish posterior Lateral Line Primordium.
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Cxcl12a induces snail1b expression to initiate collective migration and sequential Fgf-dependent neuromast formation in the zebrafish posterior lateral line Primordium.
Development (Cambridge England), 2018Co-Authors: Uma M. Neelathi, Damian Dalle Nogare, Ajay B. ChitnisAbstract:ABSTRACT The zebrafish posterior lateral line Primordium migrates along a path defined by the chemokine Cxcl12a, periodically depositing neuromasts, to pioneer formation of the zebrafish posterior lateral line system. snail1b , known for its role in promoting cell migration, is expressed in leading cells of the Primordium in response to Cxcl12a, whereas its expression in trailing cells is inhibited by Fgf signaling. snail1b knockdown delays initiation of Primordium migration. This delay is associated with aberrant expansion of epithelial cell adhesion molecule ( epcam ) and reduction of cadherin 2 expression in the leading part of the Primordium. Co-injection of snail1b morpholino with snail1b mRNA prevents the initial delay in migration and restores normal expression of epcam and cadherin 2 . The delay in initiating Primordium migration in snail1b morphants is accompanied by a delay in sequential formation of trailing Fgf signaling centers and associated protoneuromasts. This delay is not specifically associated with knockdown of snail1b but also with other manipulations that delay migration of the Primordium. These observations reveal an unexpected link between the initiation of collective migration and sequential formation of protoneuromasts in the Primordium.
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A framework for understanding morphogenesis and migration of the zebrafish posterior Lateral Line Primordium.
Mechanisms of development, 2017Co-Authors: Damian Dalle Nogare, Ajay B. ChitnisAbstract:A description of zebrafish posterior Lateral Line (pLL) Primordium development at single cell resolution together with the dynamics of Wnt, FGF, Notch and chemokine signaling in this system has allowed us to develop a framework to understand the self-organization of cell fate, morphogenesis and migration during its early development. The pLL Primordium migrates under the skin, from near the ear to the tip of the tail, periodically depositing neuromasts. Nascent neuromasts, or protoneuromasts, form sequentially within the migrating Primordium, mature, and are deposited from its trailing end. Initially broad Wnt signaling inhibits protoneuromast formation. However, protoneuromasts form sequentially in response to FGF signaling, starting from the trailing end, in the wake of a progressively shrinking Wnt system. While proliferation adds to the number of cells, the migrating Primordium progressively shrinks as its trailing cells stop moving and are deposited. As it shrinks, the length of the migrating Primordium correlates with the length of the leading Wnt system. Based on these observations we show how measuring the rate at which the Wnt system shrinks, the proliferation rate, the initial size of the Primordium, its speed, and a few additional parameters allows us to predict the pattern of neuromast formation and deposition by the migrating Primordium in both wild-type and mutant contexts. While the mechanism that links the length of the leading Wnt system to that of the Primordium remains unclear, we discuss how it might be determined by access to factors produced in the leading Wnt active zone that are required for collective migration of trailing cells. We conclude by reviewing how FGFs, produced in response to Wnt signaling in leading cells, help determine collective migration of trailing cells, while a polarized response to a self-generated chemokine gradient serves as an efficient mechanism to steer Primordium migration along its relatively long journey.
Cecilia Gallardo - One of the best experts on this subject based on the ideXlab platform.
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Anatomical and hormonal description of rootlet Primordium development along white lupin cluster root
Physiologia Plantarum, 2019Co-Authors: Cecilia Gallardo, Barbara Hufnagel, Célia Casset, Carine Alcon, Fanny Garcia, Fanchon Divol, Laurence Marquès, Patrick Doumas, Benjamin PeretAbstract:Cluster root (CR) is one of the most spectacular plant developmental adaptations to hostile environment. It can be found in a few species from a dozen botanical families, including white lupin (Lupinus albus) in the Fabaceae family. These amazing structures are produced in phosphate-deprived conditions and are made of hundreds of short roots also known as rootlets. White lupin is the only crop bearing CRs and is considered as the model species for CR studies. However, little information is available on CRs atypical development, including the molecular events that trigger their formation. To provide insights on CR formation, we performed an anatomical and cellular description of rootlet development in white lupin. Starting with a classic histological approach, we described rootlet Primordium development and defined 8 developmental stages from rootlet initiation to their emergence. Due to the major role of hormones in the developmental program of root system, we next focussed on auxin-related mechanisms. We observed the establishment of an auxin maximum through rootlet development in transgenic roots expressing the DR5:GUS auxin reporter. Expression analysis of the main auxin related genes (TIR, ARF, AUX/IAA…) during a detailed time course revealed specific expression associated with the formation of the rootlet Primordium. We showed that LaTIR1b [TRANSPORT INHIBITOR RESPONSE 1b] is expressed during rootlet Primordium formation and that LaARF5 [AUXIN RESPONSE FACTOR 5] is expressed in the vasculature but absent in the Primordium itself. Altogether, our results describe the very early cellular events leading to CR formation and reveal some of the auxin-related mechanisms.
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Anatomical and hormonal description of rootlet Primordium development along white lupin cluster root.
Physiologia plantarum, 2018Co-Authors: Cecilia Gallardo, Barbara Hufnagel, Célia Casset, Carine Alcon, Fanny Garcia, Fanchon Divol, Laurence Marquès, Patrick Doumas, Benjamin PeretAbstract:Cluster root (CR) is one of the most spectacular plant developmental adaptations to hostile environment. It can be found in a few species from a dozen botanical families, including white lupin (Lupinus albus) in the Fabaceae family. These amazing structures are produced in phosphate-deprived conditions and are made of hundreds of short roots also known as rootlets. White lupin is the only crop bearing CRs and is considered as the model species for CR studies. However, little information is available on CRs atypical development, including the molecular events that trigger their formation. To provide insights on CR formation, we performed an anatomical and cellular description of rootlet development in white lupin. Starting with a classic histological approach, we described rootlet Primordium development and defined eight developmental stages from rootlet initiation to their emergence. Due to the major role of hormones in the developmental program of root system, we next focussed on auxin-related mechanisms. We observed the establishment of an auxin maximum through rootlet development in transgenic roots expressing the DR5:GUS auxin reporter. Expression analysis of the main auxin-related genes [TIR, Auxin Response Factor (ARF) and AUX/IAA] during a detailed time course revealed specific expression associated with the formation of the rootlet Primordium. We showed that L. albus TRANSPORT INHIBITOR RESPONSE 1b is expressed during rootlet Primordium formation and that L. albus AUXIN RESPONSE FACTOR 5 is expressed in the vasculature but absent in the Primordium itself. Altogether, our results describe the very early cellular events leading to CR formation and reveal some of the auxin-related mechanisms.
Damian Dalle Nogare - One of the best experts on this subject based on the ideXlab platform.
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Zebrafish Posterior Lateral Line Primordium migration requires interactions between a superficial sheath of motile cells and the skin.
eLife, 2020Co-Authors: Damian Dalle Nogare, Naveen Natesh, Harshad D. Vishwasrao, Hari Shroff, Ajay B. ChitnisAbstract:The Zebrafish Posterior Lateral Line Primordium migrates in a channel between the skin and somites. Its migration depends on the coordinated movement of its mesenchymal-like leading cells and trailing cells, which form epithelial rosettes, or protoneuromasts. We describe a superficial population of flat Primordium cells that wrap around deeper epithelialized cells and extend polarized lamellipodia to migrate apposed to the overlying skin. Polarization of lamellipodia extended by both superficial and deeper protoneuromast-forming cells depends on Fgf signaling. Removal of the overlying skin has similar effects on superficial and deep cells: lamellipodia are lost, blebs appear instead, and collective migration fails. When skinned embryos are embedded in Matrigel, basal and superficial lamellipodia are recovered; however, only the directionality of basal protrusions is recovered, and migration is not rescued. These observations support a key role played by superficial Primordium cells and the skin in directed migration of the Posterior Lateral Line Primordium.
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netlogo agent based models as tools for understanding the self organization of cell fate morphogenesis and collective migration of the zebrafish posterior lateral line Primordium
Seminars in Cell & Developmental Biology, 2020Co-Authors: Damian Dalle Nogare, Ajay B. ChitnisAbstract:Abstract Interactions between Primordium cells and their environment determines the self-organization of the zebrafish posterior Lateral Line Primordium as it migrates under the skin from the ear to the tip of the tail forming and depositing neuromasts to spearhead formation of the posterior Lateral Line sensory system. In this review we describe how the NetLogo agent-based programming environment has been used in our lab to visualize and explore how self-generated chemokine gradients determine collective migration, how the dynamics of Wnt signaling can be used to predict patterns of neuromast deposition, and how previously defined interactions between Wnt and Fgf signaling systems have the potential to determine the periodic formation of center-biased Fgf signaling centers in the wake of a shrinking Wnt system. We also describe how NetLogo was used as a database for storing and visualizing the results of in toto lineage analysis of all cells in the migrating Primordium. Together, the models illustrate how this programming environment can be used in diverse ways to integrate what has been learnt from biological experiments about the nature of interactions between cells and their environment, and explore how these interactions could potentially determine emergent patterns of cell fate specification, morphogenesis and collective migration of the zebrafish posterior Lateral Line Primordium.
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Cxcl12a induces snail1b expression to initiate collective migration and sequential Fgf-dependent neuromast formation in the zebrafish posterior lateral line Primordium.
Development (Cambridge England), 2018Co-Authors: Uma M. Neelathi, Damian Dalle Nogare, Ajay B. ChitnisAbstract:ABSTRACT The zebrafish posterior lateral line Primordium migrates along a path defined by the chemokine Cxcl12a, periodically depositing neuromasts, to pioneer formation of the zebrafish posterior lateral line system. snail1b , known for its role in promoting cell migration, is expressed in leading cells of the Primordium in response to Cxcl12a, whereas its expression in trailing cells is inhibited by Fgf signaling. snail1b knockdown delays initiation of Primordium migration. This delay is associated with aberrant expansion of epithelial cell adhesion molecule ( epcam ) and reduction of cadherin 2 expression in the leading part of the Primordium. Co-injection of snail1b morpholino with snail1b mRNA prevents the initial delay in migration and restores normal expression of epcam and cadherin 2 . The delay in initiating Primordium migration in snail1b morphants is accompanied by a delay in sequential formation of trailing Fgf signaling centers and associated protoneuromasts. This delay is not specifically associated with knockdown of snail1b but also with other manipulations that delay migration of the Primordium. These observations reveal an unexpected link between the initiation of collective migration and sequential formation of protoneuromasts in the Primordium.
-
A framework for understanding morphogenesis and migration of the zebrafish posterior Lateral Line Primordium.
Mechanisms of development, 2017Co-Authors: Damian Dalle Nogare, Ajay B. ChitnisAbstract:A description of zebrafish posterior Lateral Line (pLL) Primordium development at single cell resolution together with the dynamics of Wnt, FGF, Notch and chemokine signaling in this system has allowed us to develop a framework to understand the self-organization of cell fate, morphogenesis and migration during its early development. The pLL Primordium migrates under the skin, from near the ear to the tip of the tail, periodically depositing neuromasts. Nascent neuromasts, or protoneuromasts, form sequentially within the migrating Primordium, mature, and are deposited from its trailing end. Initially broad Wnt signaling inhibits protoneuromast formation. However, protoneuromasts form sequentially in response to FGF signaling, starting from the trailing end, in the wake of a progressively shrinking Wnt system. While proliferation adds to the number of cells, the migrating Primordium progressively shrinks as its trailing cells stop moving and are deposited. As it shrinks, the length of the migrating Primordium correlates with the length of the leading Wnt system. Based on these observations we show how measuring the rate at which the Wnt system shrinks, the proliferation rate, the initial size of the Primordium, its speed, and a few additional parameters allows us to predict the pattern of neuromast formation and deposition by the migrating Primordium in both wild-type and mutant contexts. While the mechanism that links the length of the leading Wnt system to that of the Primordium remains unclear, we discuss how it might be determined by access to factors produced in the leading Wnt active zone that are required for collective migration of trailing cells. We conclude by reviewing how FGFs, produced in response to Wnt signaling in leading cells, help determine collective migration of trailing cells, while a polarized response to a self-generated chemokine gradient serves as an efficient mechanism to steer Primordium migration along its relatively long journey.
Célia Casset - One of the best experts on this subject based on the ideXlab platform.
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Anatomical and hormonal description of rootlet Primordium development along white lupin cluster root
Physiologia Plantarum, 2019Co-Authors: Cecilia Gallardo, Barbara Hufnagel, Célia Casset, Carine Alcon, Fanny Garcia, Fanchon Divol, Laurence Marquès, Patrick Doumas, Benjamin PeretAbstract:Cluster root (CR) is one of the most spectacular plant developmental adaptations to hostile environment. It can be found in a few species from a dozen botanical families, including white lupin (Lupinus albus) in the Fabaceae family. These amazing structures are produced in phosphate-deprived conditions and are made of hundreds of short roots also known as rootlets. White lupin is the only crop bearing CRs and is considered as the model species for CR studies. However, little information is available on CRs atypical development, including the molecular events that trigger their formation. To provide insights on CR formation, we performed an anatomical and cellular description of rootlet development in white lupin. Starting with a classic histological approach, we described rootlet Primordium development and defined 8 developmental stages from rootlet initiation to their emergence. Due to the major role of hormones in the developmental program of root system, we next focussed on auxin-related mechanisms. We observed the establishment of an auxin maximum through rootlet development in transgenic roots expressing the DR5:GUS auxin reporter. Expression analysis of the main auxin related genes (TIR, ARF, AUX/IAA…) during a detailed time course revealed specific expression associated with the formation of the rootlet Primordium. We showed that LaTIR1b [TRANSPORT INHIBITOR RESPONSE 1b] is expressed during rootlet Primordium formation and that LaARF5 [AUXIN RESPONSE FACTOR 5] is expressed in the vasculature but absent in the Primordium itself. Altogether, our results describe the very early cellular events leading to CR formation and reveal some of the auxin-related mechanisms.
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Anatomical and hormonal description of rootlet Primordium development along white lupin cluster root.
Physiologia plantarum, 2018Co-Authors: Cecilia Gallardo, Barbara Hufnagel, Célia Casset, Carine Alcon, Fanny Garcia, Fanchon Divol, Laurence Marquès, Patrick Doumas, Benjamin PeretAbstract:Cluster root (CR) is one of the most spectacular plant developmental adaptations to hostile environment. It can be found in a few species from a dozen botanical families, including white lupin (Lupinus albus) in the Fabaceae family. These amazing structures are produced in phosphate-deprived conditions and are made of hundreds of short roots also known as rootlets. White lupin is the only crop bearing CRs and is considered as the model species for CR studies. However, little information is available on CRs atypical development, including the molecular events that trigger their formation. To provide insights on CR formation, we performed an anatomical and cellular description of rootlet development in white lupin. Starting with a classic histological approach, we described rootlet Primordium development and defined eight developmental stages from rootlet initiation to their emergence. Due to the major role of hormones in the developmental program of root system, we next focussed on auxin-related mechanisms. We observed the establishment of an auxin maximum through rootlet development in transgenic roots expressing the DR5:GUS auxin reporter. Expression analysis of the main auxin-related genes [TIR, Auxin Response Factor (ARF) and AUX/IAA] during a detailed time course revealed specific expression associated with the formation of the rootlet Primordium. We showed that L. albus TRANSPORT INHIBITOR RESPONSE 1b is expressed during rootlet Primordium formation and that L. albus AUXIN RESPONSE FACTOR 5 is expressed in the vasculature but absent in the Primordium itself. Altogether, our results describe the very early cellular events leading to CR formation and reveal some of the auxin-related mechanisms.
