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Maurijn Van Der Zee - One of the best experts on this subject based on the ideXlab platform.
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Immune competence in insect eggs depends on the extraembryonic Serosa.
Developmental and comparative immunology, 2013Co-Authors: Chris G C Jacobs, Maurijn Van Der ZeeAbstract:Innate immunity is common to all metazoans and serves as a first line of defense against pathogens. Although the immune response of adult and larval insects has been well characterized, it remains unknown whether the insect egg is able to mount an immune response. Contrary to Drosophila, Tribolium eggs develop an extraembryonic epithelium, the Serosa. Epithelia are well known for their ability to fight infection, so the Serosa has the potential to protect the embryo against pathogens. To test this hypothesis we created Serosa-less eggs by Tc-zen1 parental RNAi. We found that the Tribolium egg upregulates several immune genes to comparable levels as adults in response to infection. Drosophila eggs and Serosa-less Tribolium eggs, however, show little to no upregulation of any of the tested immune genes. We conclude that the extraembryonic Serosa is crucial for the early immune competence of the Tribolium egg.
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Distinct Functions of the Tribolium zerknu¨llt Genes in Serosa Specification and Dorsal Closure
Current biology : CB, 2005Co-Authors: Maurijn Van Der Zee, Nicola Berns, Siegfried RothAbstract:Summary Background: In the long-germ insect Drosophila , a single extraembryonic membrane, the amnioSerosa, covers the embryo at the dorsal side. In ancestral short-germ insects, an inner membrane, the amnion, covers the embryo ventrally, and an outer membrane, the Serosa, completely surrounds the embryo. An early differentiation step partitions the uniform blastoderm into the anterior-dorsal Serosa and the posterior-ventral germ rudiment giving rise to amnion and embryo proper. In Drosophila , amnioSerosa formation depends on the dorsoventral patterning gene zerknu¨llt ( zen ), a derived Hox3 gene. Results: The short-germ beetle Tribolium castaneum possesses two zen homologs, Tc-zen1 and Tc-zen2 . Tc-zen1 acts early and specifies the Serosa. The loss of the Serosa after Tc-zen1 RNAi is compensated by an expansion of the entire germ rudiment toward the anterior. Instead of the Serosa, the amnion covers the embryo at the dorsal side, and later size regulation normalizes the early fate shifts, revealing a high degree of plasticity of short-germ development. Tc-zen2 acts later and initiates the amnion and Serosa fusion required for dorsal closure. After Tc-zen2 RNAi, the amnion and Serosa stay apart, and the embryo closes ventrally, assuming a completely everted (inside-out) topology. Conclusions: In Tribolium , the duplication of the zen genes was accompanied by subfunctionalization. One of the paralogues, Tc-zen1 , acts as an early anterior-posterior patterning gene by specifying the Serosa. In absence of the Serosa, Tribolium embryogenesis acquires features of long-germ development with a single extraembryonic membrane. We discuss implications for the evolution of insect development including the origin of the zen -derived anterior determinant bicoid .
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distinct functions of the tribolium zerknu llt genes in Serosa specification and dorsal closure
Current Biology, 2005Co-Authors: Maurijn Van Der Zee, Nicola Berns, Siegfried RothAbstract:Summary Background: In the long-germ insect Drosophila , a single extraembryonic membrane, the amnioSerosa, covers the embryo at the dorsal side. In ancestral short-germ insects, an inner membrane, the amnion, covers the embryo ventrally, and an outer membrane, the Serosa, completely surrounds the embryo. An early differentiation step partitions the uniform blastoderm into the anterior-dorsal Serosa and the posterior-ventral germ rudiment giving rise to amnion and embryo proper. In Drosophila , amnioSerosa formation depends on the dorsoventral patterning gene zerknu¨llt ( zen ), a derived Hox3 gene. Results: The short-germ beetle Tribolium castaneum possesses two zen homologs, Tc-zen1 and Tc-zen2 . Tc-zen1 acts early and specifies the Serosa. The loss of the Serosa after Tc-zen1 RNAi is compensated by an expansion of the entire germ rudiment toward the anterior. Instead of the Serosa, the amnion covers the embryo at the dorsal side, and later size regulation normalizes the early fate shifts, revealing a high degree of plasticity of short-germ development. Tc-zen2 acts later and initiates the amnion and Serosa fusion required for dorsal closure. After Tc-zen2 RNAi, the amnion and Serosa stay apart, and the embryo closes ventrally, assuming a completely everted (inside-out) topology. Conclusions: In Tribolium , the duplication of the zen genes was accompanied by subfunctionalization. One of the paralogues, Tc-zen1 , acts as an early anterior-posterior patterning gene by specifying the Serosa. In absence of the Serosa, Tribolium embryogenesis acquires features of long-germ development with a single extraembryonic membrane. We discuss implications for the evolution of insect development including the origin of the zen -derived anterior determinant bicoid .
Siegfried Roth - One of the best experts on this subject based on the ideXlab platform.
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Distinct Functions of the Tribolium zerknu¨llt Genes in Serosa Specification and Dorsal Closure
Current biology : CB, 2005Co-Authors: Maurijn Van Der Zee, Nicola Berns, Siegfried RothAbstract:Summary Background: In the long-germ insect Drosophila , a single extraembryonic membrane, the amnioSerosa, covers the embryo at the dorsal side. In ancestral short-germ insects, an inner membrane, the amnion, covers the embryo ventrally, and an outer membrane, the Serosa, completely surrounds the embryo. An early differentiation step partitions the uniform blastoderm into the anterior-dorsal Serosa and the posterior-ventral germ rudiment giving rise to amnion and embryo proper. In Drosophila , amnioSerosa formation depends on the dorsoventral patterning gene zerknu¨llt ( zen ), a derived Hox3 gene. Results: The short-germ beetle Tribolium castaneum possesses two zen homologs, Tc-zen1 and Tc-zen2 . Tc-zen1 acts early and specifies the Serosa. The loss of the Serosa after Tc-zen1 RNAi is compensated by an expansion of the entire germ rudiment toward the anterior. Instead of the Serosa, the amnion covers the embryo at the dorsal side, and later size regulation normalizes the early fate shifts, revealing a high degree of plasticity of short-germ development. Tc-zen2 acts later and initiates the amnion and Serosa fusion required for dorsal closure. After Tc-zen2 RNAi, the amnion and Serosa stay apart, and the embryo closes ventrally, assuming a completely everted (inside-out) topology. Conclusions: In Tribolium , the duplication of the zen genes was accompanied by subfunctionalization. One of the paralogues, Tc-zen1 , acts as an early anterior-posterior patterning gene by specifying the Serosa. In absence of the Serosa, Tribolium embryogenesis acquires features of long-germ development with a single extraembryonic membrane. We discuss implications for the evolution of insect development including the origin of the zen -derived anterior determinant bicoid .
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distinct functions of the tribolium zerknu llt genes in Serosa specification and dorsal closure
Current Biology, 2005Co-Authors: Maurijn Van Der Zee, Nicola Berns, Siegfried RothAbstract:Summary Background: In the long-germ insect Drosophila , a single extraembryonic membrane, the amnioSerosa, covers the embryo at the dorsal side. In ancestral short-germ insects, an inner membrane, the amnion, covers the embryo ventrally, and an outer membrane, the Serosa, completely surrounds the embryo. An early differentiation step partitions the uniform blastoderm into the anterior-dorsal Serosa and the posterior-ventral germ rudiment giving rise to amnion and embryo proper. In Drosophila , amnioSerosa formation depends on the dorsoventral patterning gene zerknu¨llt ( zen ), a derived Hox3 gene. Results: The short-germ beetle Tribolium castaneum possesses two zen homologs, Tc-zen1 and Tc-zen2 . Tc-zen1 acts early and specifies the Serosa. The loss of the Serosa after Tc-zen1 RNAi is compensated by an expansion of the entire germ rudiment toward the anterior. Instead of the Serosa, the amnion covers the embryo at the dorsal side, and later size regulation normalizes the early fate shifts, revealing a high degree of plasticity of short-germ development. Tc-zen2 acts later and initiates the amnion and Serosa fusion required for dorsal closure. After Tc-zen2 RNAi, the amnion and Serosa stay apart, and the embryo closes ventrally, assuming a completely everted (inside-out) topology. Conclusions: In Tribolium , the duplication of the zen genes was accompanied by subfunctionalization. One of the paralogues, Tc-zen1 , acts as an early anterior-posterior patterning gene by specifying the Serosa. In absence of the Serosa, Tribolium embryogenesis acquires features of long-germ development with a single extraembryonic membrane. We discuss implications for the evolution of insect development including the origin of the zen -derived anterior determinant bicoid .
Nicola Berns - One of the best experts on this subject based on the ideXlab platform.
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Distinct Functions of the Tribolium zerknu¨llt Genes in Serosa Specification and Dorsal Closure
Current biology : CB, 2005Co-Authors: Maurijn Van Der Zee, Nicola Berns, Siegfried RothAbstract:Summary Background: In the long-germ insect Drosophila , a single extraembryonic membrane, the amnioSerosa, covers the embryo at the dorsal side. In ancestral short-germ insects, an inner membrane, the amnion, covers the embryo ventrally, and an outer membrane, the Serosa, completely surrounds the embryo. An early differentiation step partitions the uniform blastoderm into the anterior-dorsal Serosa and the posterior-ventral germ rudiment giving rise to amnion and embryo proper. In Drosophila , amnioSerosa formation depends on the dorsoventral patterning gene zerknu¨llt ( zen ), a derived Hox3 gene. Results: The short-germ beetle Tribolium castaneum possesses two zen homologs, Tc-zen1 and Tc-zen2 . Tc-zen1 acts early and specifies the Serosa. The loss of the Serosa after Tc-zen1 RNAi is compensated by an expansion of the entire germ rudiment toward the anterior. Instead of the Serosa, the amnion covers the embryo at the dorsal side, and later size regulation normalizes the early fate shifts, revealing a high degree of plasticity of short-germ development. Tc-zen2 acts later and initiates the amnion and Serosa fusion required for dorsal closure. After Tc-zen2 RNAi, the amnion and Serosa stay apart, and the embryo closes ventrally, assuming a completely everted (inside-out) topology. Conclusions: In Tribolium , the duplication of the zen genes was accompanied by subfunctionalization. One of the paralogues, Tc-zen1 , acts as an early anterior-posterior patterning gene by specifying the Serosa. In absence of the Serosa, Tribolium embryogenesis acquires features of long-germ development with a single extraembryonic membrane. We discuss implications for the evolution of insect development including the origin of the zen -derived anterior determinant bicoid .
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distinct functions of the tribolium zerknu llt genes in Serosa specification and dorsal closure
Current Biology, 2005Co-Authors: Maurijn Van Der Zee, Nicola Berns, Siegfried RothAbstract:Summary Background: In the long-germ insect Drosophila , a single extraembryonic membrane, the amnioSerosa, covers the embryo at the dorsal side. In ancestral short-germ insects, an inner membrane, the amnion, covers the embryo ventrally, and an outer membrane, the Serosa, completely surrounds the embryo. An early differentiation step partitions the uniform blastoderm into the anterior-dorsal Serosa and the posterior-ventral germ rudiment giving rise to amnion and embryo proper. In Drosophila , amnioSerosa formation depends on the dorsoventral patterning gene zerknu¨llt ( zen ), a derived Hox3 gene. Results: The short-germ beetle Tribolium castaneum possesses two zen homologs, Tc-zen1 and Tc-zen2 . Tc-zen1 acts early and specifies the Serosa. The loss of the Serosa after Tc-zen1 RNAi is compensated by an expansion of the entire germ rudiment toward the anterior. Instead of the Serosa, the amnion covers the embryo at the dorsal side, and later size regulation normalizes the early fate shifts, revealing a high degree of plasticity of short-germ development. Tc-zen2 acts later and initiates the amnion and Serosa fusion required for dorsal closure. After Tc-zen2 RNAi, the amnion and Serosa stay apart, and the embryo closes ventrally, assuming a completely everted (inside-out) topology. Conclusions: In Tribolium , the duplication of the zen genes was accompanied by subfunctionalization. One of the paralogues, Tc-zen1 , acts as an early anterior-posterior patterning gene by specifying the Serosa. In absence of the Serosa, Tribolium embryogenesis acquires features of long-germ development with a single extraembryonic membrane. We discuss implications for the evolution of insect development including the origin of the zen -derived anterior determinant bicoid .
Urs Schmidtott - One of the best experts on this subject based on the ideXlab platform.
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postgastrular zen expression is required to develop distinct amniotic and Serosal epithelia in the scuttle fly megaselia
Developmental Biology, 2010Co-Authors: Ab Matteen Rafiqi, Steffen Lemke, Urs SchmidtottAbstract:The amnioSerosa is an extraembryonic epithelium that evolved in higher cyclorrhaphan flies from distinct Serosal and amniotic epithelia. The underlying genetic mechanism of this evolutionary transition is unknown. AmnioSerosa development of Drosophila correlates with novel expression characteristics of the homeobox gene zerknullt (zen), including a broad zen expression domain in the syncytial blastoderm and the complete absence of postgastrular zen expression. Here we examine the functional significance of these features by altering the activity profile of zen in Megaselia (a lower cyclorrhaphan fly with distinct Serosal and amniotic epithelia) and Drosophila, and by examining in Megaselia the function of u-shaped group (ush-group) genes, which in Drosophila maintain the amnioSerosa after gastrulation when zen is no longer expressed. In Megaselia, loss of postgastrular zen expression abrogates Serosa development but allows amnion development. Ectopic expression of zen in early Megaselia embryos allows Serosa formation but perturbs amnion development. Megaselia homologues of u-shaped group genes are not essential for Serosa formation but mediate germband retraction and dorsal closure. Finally, ectopic postgastrular zen expression in Drosophila causes an enlargement of amnioSerosa cells and interferes with the morphogenetic functions of the amnioSerosa. Our results suggest that the origin of the amnioSerosa involved the loss of postgastrular zen expression from extraembryonic tissue, that the early broad expression domain of Drosophila zen evolved afterwards, and that the ush-group genes ancestrally played a role in morphogenetic functions of the amnion.
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evolutionary origin of the amnioSerosa in cyclorrhaphan flies correlates with spatial and temporal expression changes of zen
Proceedings of the National Academy of Sciences of the United States of America, 2008Co-Authors: Ab Matteen Rafiqi, Steffen Lemke, Sean Ferguson, Michael Stauber, Urs SchmidtottAbstract:Abstract Higher cyclorrhaphan flies including Drosophila develop a single extraembryonic epithelium (amnioSerosa), which closes the germband dorsally. In most other insects two extraembryonic epithelia, Serosa and amnion, line the inner eggshell and the ventral germband, respectively. How the two extraembryonic epithelia evolved into one is unclear. Recent studies have shown that, in the flour beetle Tribolium and in the milkweed bug Oncopeltus, the homeobox gene zerknullt (zen) controls the fusion of the amnion with the Serosa before dorsal closure. To understand the origin of the amnioSerosa in evolution, we examined the expression and function of zen in the extraembryonic tissue of lower Cyclorrhapha. We show that Megaselia abdita (Phoridae) and Episyrphus balteatus (Syrphidae) develop a Serosa and a dorsal amnion, suggesting that a dorsal amnion preceded the origin of the amnioSerosa in evolution. Using Kruppel (Kr) and pannier (pnr) homologues of Megaselia as markers for Serosal and amniotic tissue, respectively, we show that after zen RNAi all extraembryonic tissue becomes indistinguishable from amniotic cells, like in Tribolium but unlike in Drosophila, in which zen controls all aspects of extraembryonic development. Compared with Megaselia and Episyrphus, zen expression in Drosophila is extended to cells that form the amnion in lower Cyclorrhapha and is down-regulated at the developmental stage, when Serosa cells in lower Cyclorrhapha begin to expand. These expression differences between species with distinct extraembryonic tissue organizations and the conserved requirement of zen for Serosa development suggest that the origin of an amnioSerosa-like epithelium was accompanied by expression changes of zen. Megaselia Episyrphus Drosophila EvoDevo homology
Amin A. Milki - One of the best experts on this subject based on the ideXlab platform.
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Endometrioma of uterine Serosa in a woman with mosaic Turner’s syndrome receiving hormone replacement therapy: Case report
Human reproduction (Oxford England), 2002Co-Authors: Salli I. Tazuke, Amin A. MilkiAbstract:Endometriosis in Turner's syndrome patients has only been reported in five isolated cases. We present here an endometrioma on the uterine Serosa and pelvic endometriosis arising in a mosaic Turner's patient receiving hormone replacement therapy (HRT). The 24 year old patient with mosaic Turner's syndrome [45,X; 46,X pseudo dicentric Y (q11.23)], on cyclic HRT after laparoscopic gonadectomy 5 years previously, was found to have an adnexal mass on routine examination. Given her history, due to the fear of a malignant process arising from a potential gonadal remnant, she underwent a laparoscopy and was found to have a 5 cm Serosal endometrioma arising on a stalk from the uterine fundal surface as well as pelvic endometriosis. De-novo endometrioma and endometriosis occurred in a mosaic Turner's patient after gonadectomy on cyclic HRT. The presentation was also unusual with a pedunculated endometrioma arising from the uterine Serosa. Due to the fact that the patient did have cyclic menstrual flow, her endometriosis may have arisen from retrograde menstruation or coelomic metaplasia induced by exogenous hormones.
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endometrioma of uterine Serosa in a woman with mosaic turner s syndrome receiving hormone replacement therapy case report
Human Reproduction, 2002Co-Authors: Salli I. Tazuke, Amin A. MilkiAbstract:Endometriosis in Turner's syndrome patients has only been reported in five isolated cases. We present here an endometrioma on the uterine Serosa and pelvic endometriosis arising in a mosaic Turner's patient receiving hormone replacement therapy (HRT). The 24 year old patient with mosaic Turner's syndrome [45,X; 46,X pseudo dicentric Y (q11.23)], on cyclic HRT after laparoscopic gonadectomy 5 years previously, was found to have an adnexal mass on routine examination. Given her history, due to the fear of a malignant process arising from a potential gonadal remnant, she underwent a laparoscopy and was found to have a 5 cm Serosal endometrioma arising on a stalk from the uterine fundal surface as well as pelvic endometriosis. De-novo endometrioma and endometriosis occurred in a mosaic Turner's patient after gonadectomy on cyclic HRT. The presentation was also unusual with a pedunculated endometrioma arising from the uterine Serosa. Due to the fact that the patient did have cyclic menstrual flow, her endometriosis may have arisen from retrograde menstruation or coelomic metaplasia induced by exogenous hormones.
