Dr. Tania Rozario | Rozario Lab

Bio:
Tania Rozario got her PhD from the University of Virginia studying embryonic development. During her postdoc she joined Phil Newmark's lab (Morgridge Institute for Research, WI) to study planarian regeneration but pivoted toward their parasitic cousins- tapeworms. Her work (re)established the rat tapeworm, Hymenolepis diminuta, as a non-traditional model to explore the molecular mechanisms that govern how tapeworms grow, regenerate, and reproduce at prolific rates. In 2021, she established her independent lab at the University of Georgia where her work understanding extrinsic and intrinsic signals that regulate tapeworm stem cells continues.

Abstract:
Tapeworms grow at rates that rival all metazoan tissues, including during embryonic and neoplastic growth. The rat tapeworm, Hymenolepis diminuta, produces up to 2,200 proglottids (segments), increasing in length up to 3,400 fold, and weight up to 1.8 million fold within the first 15 days of infection. Tapeworms can also regenerate: they shed large parts of their body, releasing their embryos to continue their life cycle, yet are able to continuously replenish proglottids and maintain an equilibrium length. Despite their impressive feats of growth, regeneration-competence is limited to one anatomical region- the neck. Using transcriptomics and RNA interference we have functionally validated the first molecular regulators of tapeworm regeneration and demonstrated that regeneration is dependent on a large population of poorly understood stem cells. Uncovering neck-exclusive stem cell subpopulations that can explain regionally restricted regeneration has remained elusive. Instead, we find that lethally irradiated tapeworms can be rescued from death when cells from both regeneration-competent and regeneration-incompetent regions are transplanted into the neck, suggesting that extrinsic signals at the neck are crucial for regeneration. In pursuit of such signals, we have discovered that the head has an organizer-like function. The head both maintains neck identity and regulates stem cell proliferation by establishing polarized expression patterns of Wnt signaling components like sfrp and beta-catenin. Our work is beginning to elucidate how the head and neck provide a rich signaling environment that enables region-specific regeneration in tapeworms.
 

Watch the seminar here!

Dr. Tania Rozario | Rozario Lab

Bio:
Tania Rozario got her PhD from the University of Virginia studying embryonic development. During her postdoc she joined Phil Newmark's lab (Morgridge Institute for Research, WI) to study planarian regeneration but pivoted toward their parasitic cousins- tapeworms. Her work (re)established the rat tapeworm, Hymenolepis diminuta, as a non-traditional model to explore the molecular mechanisms that govern how tapeworms grow, regenerate, and reproduce at prolific rates. In 2021, she established her independent lab at the University of Georgia where her work understanding extrinsic and intrinsic signals that regulate tapeworm stem cells continues.

Abstract:
Tapeworms grow at rates that rival all metazoan tissues, including during embryonic and neoplastic growth. The rat tapeworm, Hymenolepis diminuta, produces up to 2,200 proglottids (segments), increasing in length up to 3,400 fold, and weight up to 1.8 million fold within the first 15 days of infection. Tapeworms can also regenerate: they shed large parts of their body, releasing their embryos to continue their life cycle, yet are able to continuously replenish proglottids and maintain an equilibrium length. Despite their impressive feats of growth, regeneration-competence is limited to one anatomical region- the neck. Using transcriptomics and RNA interference we have functionally validated the first molecular regulators of tapeworm regeneration and demonstrated that regeneration is dependent on a large population of poorly understood stem cells. Uncovering neck-exclusive stem cell subpopulations that can explain regionally restricted regeneration has remained elusive. Instead, we find that lethally irradiated tapeworms can be rescued from death when cells from both regeneration-competent and regeneration-incompetent regions are transplanted into the neck, suggesting that extrinsic signals at the neck are crucial for regeneration. In pursuit of such signals, we have discovered that the head has an organizer-like function. The head both maintains neck identity and regulates stem cell proliferation by establishing polarized expression patterns of Wnt signaling components like sfrp and beta-catenin. Our work is beginning to elucidate how the head and neck provide a rich signaling environment that enables region-specific regeneration in tapeworms.
 

Watch the seminar here!

Dr. Tania Rozario | Rozario Lab

Bio:
Tania Rozario got her PhD from the University of Virginia studying embryonic development. During her postdoc she joined Phil Newmark's lab (Morgridge Institute for Research, WI) to study planarian regeneration but pivoted toward their parasitic cousins- tapeworms. Her work (re)established the rat tapeworm, Hymenolepis diminuta, as a non-traditional model to explore the molecular mechanisms that govern how tapeworms grow, regenerate, and reproduce at prolific rates. In 2021, she established her independent lab at the University of Georgia where her work understanding extrinsic and intrinsic signals that regulate tapeworm stem cells continues.

Abstract:
Tapeworms grow at rates that rival all metazoan tissues, including during embryonic and neoplastic growth. The rat tapeworm, Hymenolepis diminuta, produces up to 2,200 proglottids (segments), increasing in length up to 3,400 fold, and weight up to 1.8 million fold within the first 15 days of infection. Tapeworms can also regenerate: they shed large parts of their body, releasing their embryos to continue their life cycle, yet are able to continuously replenish proglottids and maintain an equilibrium length. Despite their impressive feats of growth, regeneration-competence is limited to one anatomical region- the neck. Using transcriptomics and RNA interference we have functionally validated the first molecular regulators of tapeworm regeneration and demonstrated that regeneration is dependent on a large population of poorly understood stem cells. Uncovering neck-exclusive stem cell subpopulations that can explain regionally restricted regeneration has remained elusive. Instead, we find that lethally irradiated tapeworms can be rescued from death when cells from both regeneration-competent and regeneration-incompetent regions are transplanted into the neck, suggesting that extrinsic signals at the neck are crucial for regeneration. In pursuit of such signals, we have discovered that the head has an organizer-like function. The head both maintains neck identity and regulates stem cell proliferation by establishing polarized expression patterns of Wnt signaling components like sfrp and beta-catenin. Our work is beginning to elucidate how the head and neck provide a rich signaling environment that enables region-specific regeneration in tapeworms.
 

Watch the seminar here!

Dr. Tania Rozario | Rozario Lab

Bio:
Tania Rozario got her PhD from the University of Virginia studying embryonic development. During her postdoc she joined Phil Newmark's lab (Morgridge Institute for Research, WI) to study planarian regeneration but pivoted toward their parasitic cousins- tapeworms. Her work (re)established the rat tapeworm, Hymenolepis diminuta, as a non-traditional model to explore the molecular mechanisms that govern how tapeworms grow, regenerate, and reproduce at prolific rates. In 2021, she established her independent lab at the University of Georgia where her work understanding extrinsic and intrinsic signals that regulate tapeworm stem cells continues.

Abstract:
Tapeworms grow at rates that rival all metazoan tissues, including during embryonic and neoplastic growth. The rat tapeworm, Hymenolepis diminuta, produces up to 2,200 proglottids (segments), increasing in length up to 3,400 fold, and weight up to 1.8 million fold within the first 15 days of infection. Tapeworms can also regenerate: they shed large parts of their body, releasing their embryos to continue their life cycle, yet are able to continuously replenish proglottids and maintain an equilibrium length. Despite their impressive feats of growth, regeneration-competence is limited to one anatomical region- the neck. Using transcriptomics and RNA interference we have functionally validated the first molecular regulators of tapeworm regeneration and demonstrated that regeneration is dependent on a large population of poorly understood stem cells. Uncovering neck-exclusive stem cell subpopulations that can explain regionally restricted regeneration has remained elusive. Instead, we find that lethally irradiated tapeworms can be rescued from death when cells from both regeneration-competent and regeneration-incompetent regions are transplanted into the neck, suggesting that extrinsic signals at the neck are crucial for regeneration. In pursuit of such signals, we have discovered that the head has an organizer-like function. The head both maintains neck identity and regulates stem cell proliferation by establishing polarized expression patterns of Wnt signaling components like sfrp and beta-catenin. Our work is beginning to elucidate how the head and neck provide a rich signaling environment that enables region-specific regeneration in tapeworms.
 

Watch the seminar here!

Click here for more information on Dr. Joseph Takahashi.

Click here for more information on Dr. Joseph Takahashi.

Click here for more information on Dr. Joseph Takahashi.

Click here for more information on Dr. Joseph Takahashi.

Dr. Chelsea Specht | Specht Lab

Bio:
Dr. Chelsea Specht is the Barbara McClintock Professor of Plant Biology and Associate Director for Faculty Development, Equity, and Inclusion in the School of Integrative Plant Science and serves as the elected Associate Dean of Faculty for Cornell University.   She is a faculty member in the graduate fields of Plant Biology and Ecology and Evolutionary Biology and a faculty fellow of the Atkinson Center for a Sustainable Future.  She is also a member of the L.H. Bailey Hortorium and affiliated with the Cornell University Herbarium. 

In the Specht Lab we work together to investigate the evolution and diversification of Plant Form and Function. We use traditional morphological and developmental techniques combined with molecular genetics, comparative genomics and evolutionary biology to study the natural diversity of plants and to help better understand the forces creating and sustaining this diversity.  Our research incorporates elements of systematics, developmental genetics and molecular evolution to study the patterns and processes associated with plant speciation and diversification.  We take advantage of living and preserved collections to advance our research in plant systematics, biogeography, and developmental evolution. 

Abstract:
Fifty years since Dr. Paul J.M. Maas published his first monograph of the New World Costoideae, we continue to struggle with species boundaries and evolutionary relationships within this charasmatic lineage of tropical monocotyledonous plants.  In fact, the more we explore and discover the more questions emerge about the dynamics, patterns, and processes leading to speciation and diversification across the Neotropical Costaceae.  In this seminar, I will discuss the recent monographic revision and its critical role in establishing a framework for evolutionary and ecological studies of the Neotropical Costus lineage within a phylogenetic context.  The tempo and mode of speciation events are correlated with morphological changes that influence organismal interactions, including pollination and herbivory.  Ecologic, morphologic, and biogeographic conditions that appear to promote hybridization and result in the potential for hybrid speciation are discussed across the genus, and implications for developing a stable taxonomy – and whether or not that is even possible or desirable – will be discussed.

Dr. Chelsea Specht | Specht Lab

Bio:
Dr. Chelsea Specht is the Barbara McClintock Professor of Plant Biology and Associate Director for Faculty Development, Equity, and Inclusion in the School of Integrative Plant Science and serves as the elected Associate Dean of Faculty for Cornell University.   She is a faculty member in the graduate fields of Plant Biology and Ecology and Evolutionary Biology and a faculty fellow of the Atkinson Center for a Sustainable Future.  She is also a member of the L.H. Bailey Hortorium and affiliated with the Cornell University Herbarium. 

In the Specht Lab we work together to investigate the evolution and diversification of Plant Form and Function. We use traditional morphological and developmental techniques combined with molecular genetics, comparative genomics and evolutionary biology to study the natural diversity of plants and to help better understand the forces creating and sustaining this diversity.  Our research incorporates elements of systematics, developmental genetics and molecular evolution to study the patterns and processes associated with plant speciation and diversification.  We take advantage of living and preserved collections to advance our research in plant systematics, biogeography, and developmental evolution. 

Abstract:
Fifty years since Dr. Paul J.M. Maas published his first monograph of the New World Costoideae, we continue to struggle with species boundaries and evolutionary relationships within this charasmatic lineage of tropical monocotyledonous plants.  In fact, the more we explore and discover the more questions emerge about the dynamics, patterns, and processes leading to speciation and diversification across the Neotropical Costaceae.  In this seminar, I will discuss the recent monographic revision and its critical role in establishing a framework for evolutionary and ecological studies of the Neotropical Costus lineage within a phylogenetic context.  The tempo and mode of speciation events are correlated with morphological changes that influence organismal interactions, including pollination and herbivory.  Ecologic, morphologic, and biogeographic conditions that appear to promote hybridization and result in the potential for hybrid speciation are discussed across the genus, and implications for developing a stable taxonomy – and whether or not that is even possible or desirable – will be discussed.