The Experts below are selected from a list of 411 Experts worldwide ranked by ideXlab platform
Rolf Jessberger - One of the best experts on this subject based on the ideXlab platform.
-
tdrd6 mediates early steps of spliceosome maturation in primary spermatocytes
PLOS Genetics, 2017Co-Authors: Muge Akpinar, Mathias Lesche, Grigorios Fanourgakis, Konstantinos Anasstasiadis, Andreas Dahl, Rolf JessbergerAbstract:Tudor containing protein 6 (TDRD6) is a male germ line-specific protein essential for Chromatoid Body (ChB) structure, elongated spermatid development and male fertility. Here we show that in meiotic prophase I spermatocytes TDRD6 interacts with the key protein arginine methyl transferase PRMT5, which supports splicing. TDRD6 also associates with spliceosomal core protein SmB in the absence of RNA and in an arginine methylation dependent manner. In Tdrd6-/- diplotene spermatocytes PRMT5 association with SmB and arginine dimethylation of SmB are much reduced. TDRD6 deficiency impairs the assembly of spliceosomes, which feature 3.5-fold increased levels of U5 snRNPs. In the nucleus, these deficiencies in spliceosome maturation correlate with decreased numbers of SMN-positive bodies and Cajal bodies involved in nuclear snRNP maturation. Transcriptome analysis of TDRD6-deficient diplotene spermatocytes revealed high numbers of splicing defects such as aberrant usage of intron and exons as well as aberrant representation of splice junctions. Together, this study demonstrates a novel function of TDRD6 in spliceosome maturation and mRNA splicing in prophase I spermatocytes.
-
Chromatoid Body Protein TDRD6 Supports Long 3' UTR Triggered Nonsense Mediated mRNA Decay.
Public Library of Science (PLoS), 2016Co-Authors: Grigorios Fanourgakis, Muge Akpinar, Mathias Lesche, Andreas Dahl, Rolf JessbergerAbstract:Chromatoid bodies (CBs) are spermiogenesis-specific organelles of largely unknown function. CBs harbor various RNA species, RNA-associated proteins and proteins of the tudor domain family like TDRD6, which is required for a proper CB architecture. Proteome analysis of purified CBs revealed components of the nonsense-mediated mRNA decay (NMD) machinery including UPF1. TDRD6 is essential for UPF1 localization to CBs, for UPF1-UPF2 and UPF1-MVH interactions. Upon removal of TDRD6, the association of several mRNAs with UPF1 and UPF2 is disturbed, and the long 3' UTR-stimulated but not the downstream exon-exon junction triggered pathway of NMD is impaired. Reduced association of the long 3' UTR mRNAs with UPF1 and UPF2 correlates with increased stability and enhanced translational activity. Thus, we identified TDRD6 within CBs as required for mRNA degradation, specifically the extended 3' UTR-triggered NMD pathway, and provide evidence for the requirement of NMD in spermiogenesis. This function depends on TDRD6-promoted assembly of mRNA and decay enzymes in CBs
-
Chromatoid Body Protein TDRD6 Supports Long 3’ UTR Triggered Nonsense Mediated mRNA Decay
2016Co-Authors: Grigorios Fanourgakis, Muge Akpinar, Mathias Lesche, Andreas Dahl, Rolf JessbergerAbstract:Chromatoid bodies (CBs) are spermiogenesis-specific organelles of largely unknown function. CBs harbor various RNA species, RNA-associated proteins and proteins of the tudor domain family like TDRD6, which is required for a proper CB architecture. Proteome analysis of purified CBs revealed components of the nonsense-mediated mRNA decay (NMD) machinery including UPF1. TDRD6 is essential for UPF1 localization to CBs, for UPF1-UPF2 and UPF1-MVH interactions. Upon removal of TDRD6, the association of several mRNAs with UPF1 and UPF2 is disturbed, and the long 3’ UTR-stimulated but not the downstream exon-exon junction triggered pathway of NMD is impaired. Reduced association of the long 3’ UTR mRNAs with UPF1 and UPF2 correlates with increased stability and enhanced translational activity. Thus, we identified TDRD6 within CBs as required for mRNA degradation, specifically the extended 3’ UTR-triggered NMD pathway, and provide evidence for the requirement of NMD in spermiogenesis. This function depends on TDRD6-promoted assembly of mRNA and decay enzymes in CBs.
-
tdrd6 is required for spermiogenesis Chromatoid Body architecture and regulation of mirna expression
Current Biology, 2009Co-Authors: Ana Vasileva, Rolf Jessberger, Daniela Tiedau, Adriana Firooznia, Thomas MullerreichertAbstract:Summary Background Chromatoid bodies (CBs) are characteristic spermatid organelles, which were suggested to function in RNA storage and small RNA processing but whose functions remain largely unknown. CB components include Mili, Miwi, and Tudor domain proteins such as Tdrd6, whose contribution to CB structure and function is elusive. Results We determined gametogenesis stage- and male-specific expression and localization of Tdrd6, identified a C-terminally truncated form as predominant after meiosis I, and demonstrated direct physical interaction of Tdrd6 with the CB components Mili and Miwi. Development from round into elongated spermatids is abrogated in Tdrd6 −/− mice. Their round spermatids bear "ghost" CBs, whose architecture is greatly disrupted. Mael, Miwi, and Mvh do not localize to the Tdrd6-deficient CBs, but retrotransposons are not significantly activated. However, more than 50 miRNAs are more abundant in Tdrd6 −/− testes, as are exemplary pre- and pri-miRNAs. Conclusion We conclude that Tdrd6 is essential for spermiogenesis, for CB structure, and for proper mature and precursor miRNA expression.
Kiyokazu Agata - One of the best experts on this subject based on the ideXlab platform.
-
djcbc 1 a conserved dead box rna helicase of the rck p54 me31b family is a component of rna protein complexes in planarian stem cells and neurons
Developmental Dynamics, 2007Co-Authors: Maki Yoshidakashikawa, Norito Shibata, Katsuaki Takechi, Kiyokazu AgataAbstract:The stem cells of planarians, known as neoblasts, can give rise to all cell types in planarians. Neoblasts can be identified by electron microscopy as cells with electron-dense Chromatoid bodies, which are large RNP (ribonucleoprotein) complexes, in their cytoplasm. However, the components and function of Chromatoid bodies are still relatively unknown. Here we identified a DEAD box RNA helicase gene of the RCK/p54/Me31B family from a planarian EST database and showed the localization of its product in Chromatoid bodies by immunoelectron microscopy. We named this gene Djcbc-1 (Dugesia japonica Chromatoid Body component 1). Djcbc-1 was also strongly expressed in the brain and in the germline stem cells of sexualized planarians. We observed Chromatoid Body-like electron-dense bodies in brain neurons, where DjCBC-1 was also expressed. These observations suggest that common molecular components of RNP complexes may be involved in the regulation of somatic and germline stem cells, and neurons in planarians. Departmental Dynamics 236:3436–3450, 2007. © 2007 Wiley-Liss, Inc.
-
djcbc 1 a conserved dead box rna helicase of the rck p54 me31b family is a component of rna protein complexes in planarian stem cells and neurons
Developmental Dynamics, 2007Co-Authors: Maki Yoshidakashikawa, Norito Shibata, Katsuaki Takechi, Kiyokazu AgataAbstract:The stem cells of planarians, known as neoblasts, can give rise to all cell types in planarians. Neoblasts can be identified by electron microscopy as cells with electron-dense Chromatoid bodies, which are large RNP (ribonucleoprotein) complexes, in their cytoplasm. However, the components and function of Chromatoid bodies are still relatively unknown. Here we identified a DEAD box RNA helicase gene of the RCK/p54/Me31B family from a planarian EST database and showed the localization of its product in Chromatoid bodies by immunoelectron microscopy. We named this gene Djcbc-1 (Dugesia japonica Chromatoid Body component 1). Djcbc-1 was also strongly expressed in the brain and in the germline stem cells of sexualized planarians. We observed Chromatoid Body-like electron-dense bodies in brain neurons, where DjCBC-1 was also expressed. These observations suggest that common molecular components of RNP complexes may be involved in the regulation of somatic and germline stem cells, and neurons in planarians.
-
expression of vasa vas related genes in germline cells and totipotent somatic stem cells of planarians
Developmental Biology, 1999Co-Authors: Norito Shibata, Yoshihiko Umesono, Hidefumi Orii, Takashige Sakurai, Kenji Watanabe, Kiyokazu AgataAbstract:Planarians are known for their strong regenerative ability. This ability has been considered to reside in the totipotent somatic stem cell called the "neoblast." Neoblasts contain a unique cytoplasmic structure called the "Chromatoid Body," which has similar characteristics to the germline granules of germline cells of other animals. The Chromatoid bodies decrease in number and size during cytodifferentiation and disappear in completely differentiated cells during regeneration. However, germ cells maintain the Chromatoid Body during their differentiation from neoblasts. These observations suggest that the Chromatoid Body is concerned with the totipotency of cells. To understand the molecular nature of the Chromatoid Body in the neoblast, we focused on vasa (vas)-related genes, since VAS and VAS-related proteins are known to be components of the germline granules in Drosophila and Caenorhabditis elegans. By PCR, two vas-related genes (Dugesia japonica vasa-like gene, DjvlgA and DjvlgB) were isolated, and they were shown to be expressed in germ cells. Interestingly, DjvlgA was also expressed in a number of somatic cells in the mesenchymal space. In regenerating planarians, accumulation of DjvlgA-expressing cells was observed in both the blastema and the blastema-proximal region. In X-ray-irradiated planarians, which had lost regenerative capacity, the number of DjvlgA-expressing cells decreased drastically. These results suggest that the product of DjvlgA may be a component of the Chromatoid Body and may be involved in the totipotency of the neoblast.
Maria L Dufau - One of the best experts on this subject based on the ideXlab platform.
-
targeted knock in mice with a human mutation in grth ddx25 reveals the essential role of phosphorylated grth in spermatid development during spermatogenesis
Human Molecular Genetics, 2019Co-Authors: Raghuveer Kavarthapu, Rajakumar Anbazhagan, Murugananthkumar Raju, Chonhwa Tsai Morris, James Pickel, Maria L DufauAbstract:Gonadotropin-regulated testicular RNA helicase (GRTH/DDX25) is a testis specific member of the DEAD-box family of RNA helicases expressed in meiotic and haploid germ cells which plays an essential role in spermatogenesis. There are two species of GRTH the 56 kDa non-phospho and 61 kDa phospho forms. Our early studies revealed a missense mutation (R242H) of GRTH in azoospermic men that when expressed in COS1-cells lack the phospho-form of GRTH. To investigate the role of the phospho-GRTH species in spermatogenesis, we generated a GRTH knock-in (KI) transgenic mice with the R242H mutation. GRTH-KI mice are sterile with reduced testis size, lack sperm with spermatogenic arrest at round spermatid stage and loss of the cytoplasmic phospho-GRTH species. Electron microscopy studies revealed reduction in the size of Chromatoid bodies (CB) of round spermatids (RS) and germ cell apoptosis. We observed absence of phospho-GRTH in the CB of RS. Complete loss of chromatin remodeling and related proteins such as TP2, PRM2, TSSK6 and marked reduction of their respective mRNAs and half-lives were observed in GRTH-KI mice. We showed that phospho-GRTH has a role in TP2 translation and revealed its occurrence in a 3' UTR dependent manner. These findings demonstrate the relevance of phospho-GRTH in the structure of the Chromatoid Body, spermatid development and completion of spermatogenesis and provide an avenue for the development of a male contraceptive.
-
gonadotropin regulated testicular rna helicase grth ddx25 is essential for spermatid development and completion of spermatogenesis
Proceedings of the National Academy of Sciences of the United States of America, 2004Co-Authors: Chonhwa Tsaimorris, Yi Sheng, Maria L DufauAbstract:Gonadotropin-regulated testicular RNA helicase (GRTH/Ddx25), a member of the DEAD-box protein family, is a testis-specific gonadotropin-regulated RNA helicase that is present in Leydig cells and germ cells (meiotic spermatocytes and spermatids). In this study, we observed that GRTH is present in the nucleus, cytoplasm and Chromatoid Body of germ cells, and is an integral component of messenger ribonuclear protein particles. Male mice with a null mutation in the GRTH gene displayed normal gonadotropin and androgen profiles. However, they were sterile, with azoospermia caused by a complete arrest of spermiogenesis at step 8 of round spermatids and failure to elongate. Round spermatids of the null mice showed marked diminution in the size of Chromatoid bodies. The transcription of relevant messages was not altered, but their translation was abrogated in a selective manner. Protein expression of transition proteins 1 and 2 and angiotensin-converting enzyme was completely absent, whereas that of the transcriptional activator cAMP responsive element modulator was intact. These findings indicate that GRTH participates in translational-associated events during germ cell development. Although significant apoptosis was present at the metaphase of meiosis in the GRTH-null mice, spermatogenesis proceeded to step 8 of spermiogenesis when complete arrest occurred. This progression may relate to compensatory gene function(s) and/or the observed up-regulation of DNA repair proteins Rad51 and Dmc1. This study (i) demonstrates that GRTH is essential for completion of spermatogenesis, (ii) provides insights into intrinsic requirements for spermiogenesis, and (iii) establishes a model for studies of male infertility and contraception.
Norito Shibata - One of the best experts on this subject based on the ideXlab platform.
-
djcbc 1 a conserved dead box rna helicase of the rck p54 me31b family is a component of rna protein complexes in planarian stem cells and neurons
Developmental Dynamics, 2007Co-Authors: Maki Yoshidakashikawa, Norito Shibata, Katsuaki Takechi, Kiyokazu AgataAbstract:The stem cells of planarians, known as neoblasts, can give rise to all cell types in planarians. Neoblasts can be identified by electron microscopy as cells with electron-dense Chromatoid bodies, which are large RNP (ribonucleoprotein) complexes, in their cytoplasm. However, the components and function of Chromatoid bodies are still relatively unknown. Here we identified a DEAD box RNA helicase gene of the RCK/p54/Me31B family from a planarian EST database and showed the localization of its product in Chromatoid bodies by immunoelectron microscopy. We named this gene Djcbc-1 (Dugesia japonica Chromatoid Body component 1). Djcbc-1 was also strongly expressed in the brain and in the germline stem cells of sexualized planarians. We observed Chromatoid Body-like electron-dense bodies in brain neurons, where DjCBC-1 was also expressed. These observations suggest that common molecular components of RNP complexes may be involved in the regulation of somatic and germline stem cells, and neurons in planarians. Departmental Dynamics 236:3436–3450, 2007. © 2007 Wiley-Liss, Inc.
-
djcbc 1 a conserved dead box rna helicase of the rck p54 me31b family is a component of rna protein complexes in planarian stem cells and neurons
Developmental Dynamics, 2007Co-Authors: Maki Yoshidakashikawa, Norito Shibata, Katsuaki Takechi, Kiyokazu AgataAbstract:The stem cells of planarians, known as neoblasts, can give rise to all cell types in planarians. Neoblasts can be identified by electron microscopy as cells with electron-dense Chromatoid bodies, which are large RNP (ribonucleoprotein) complexes, in their cytoplasm. However, the components and function of Chromatoid bodies are still relatively unknown. Here we identified a DEAD box RNA helicase gene of the RCK/p54/Me31B family from a planarian EST database and showed the localization of its product in Chromatoid bodies by immunoelectron microscopy. We named this gene Djcbc-1 (Dugesia japonica Chromatoid Body component 1). Djcbc-1 was also strongly expressed in the brain and in the germline stem cells of sexualized planarians. We observed Chromatoid Body-like electron-dense bodies in brain neurons, where DjCBC-1 was also expressed. These observations suggest that common molecular components of RNP complexes may be involved in the regulation of somatic and germline stem cells, and neurons in planarians.
-
expression of vasa vas related genes in germline cells and totipotent somatic stem cells of planarians
Developmental Biology, 1999Co-Authors: Norito Shibata, Yoshihiko Umesono, Hidefumi Orii, Takashige Sakurai, Kenji Watanabe, Kiyokazu AgataAbstract:Planarians are known for their strong regenerative ability. This ability has been considered to reside in the totipotent somatic stem cell called the "neoblast." Neoblasts contain a unique cytoplasmic structure called the "Chromatoid Body," which has similar characteristics to the germline granules of germline cells of other animals. The Chromatoid bodies decrease in number and size during cytodifferentiation and disappear in completely differentiated cells during regeneration. However, germ cells maintain the Chromatoid Body during their differentiation from neoblasts. These observations suggest that the Chromatoid Body is concerned with the totipotency of cells. To understand the molecular nature of the Chromatoid Body in the neoblast, we focused on vasa (vas)-related genes, since VAS and VAS-related proteins are known to be components of the germline granules in Drosophila and Caenorhabditis elegans. By PCR, two vas-related genes (Dugesia japonica vasa-like gene, DjvlgA and DjvlgB) were isolated, and they were shown to be expressed in germ cells. Interestingly, DjvlgA was also expressed in a number of somatic cells in the mesenchymal space. In regenerating planarians, accumulation of DjvlgA-expressing cells was observed in both the blastema and the blastema-proximal region. In X-ray-irradiated planarians, which had lost regenerative capacity, the number of DjvlgA-expressing cells decreased drastically. These results suggest that the product of DjvlgA may be a component of the Chromatoid Body and may be involved in the totipotency of the neoblast.
Muge Akpinar - One of the best experts on this subject based on the ideXlab platform.
-
tdrd6 mediates early steps of spliceosome maturation in primary spermatocytes
PLOS Genetics, 2017Co-Authors: Muge Akpinar, Mathias Lesche, Grigorios Fanourgakis, Konstantinos Anasstasiadis, Andreas Dahl, Rolf JessbergerAbstract:Tudor containing protein 6 (TDRD6) is a male germ line-specific protein essential for Chromatoid Body (ChB) structure, elongated spermatid development and male fertility. Here we show that in meiotic prophase I spermatocytes TDRD6 interacts with the key protein arginine methyl transferase PRMT5, which supports splicing. TDRD6 also associates with spliceosomal core protein SmB in the absence of RNA and in an arginine methylation dependent manner. In Tdrd6-/- diplotene spermatocytes PRMT5 association with SmB and arginine dimethylation of SmB are much reduced. TDRD6 deficiency impairs the assembly of spliceosomes, which feature 3.5-fold increased levels of U5 snRNPs. In the nucleus, these deficiencies in spliceosome maturation correlate with decreased numbers of SMN-positive bodies and Cajal bodies involved in nuclear snRNP maturation. Transcriptome analysis of TDRD6-deficient diplotene spermatocytes revealed high numbers of splicing defects such as aberrant usage of intron and exons as well as aberrant representation of splice junctions. Together, this study demonstrates a novel function of TDRD6 in spliceosome maturation and mRNA splicing in prophase I spermatocytes.
-
Chromatoid Body Protein TDRD6 Supports Long 3' UTR Triggered Nonsense Mediated mRNA Decay.
Public Library of Science (PLoS), 2016Co-Authors: Grigorios Fanourgakis, Muge Akpinar, Mathias Lesche, Andreas Dahl, Rolf JessbergerAbstract:Chromatoid bodies (CBs) are spermiogenesis-specific organelles of largely unknown function. CBs harbor various RNA species, RNA-associated proteins and proteins of the tudor domain family like TDRD6, which is required for a proper CB architecture. Proteome analysis of purified CBs revealed components of the nonsense-mediated mRNA decay (NMD) machinery including UPF1. TDRD6 is essential for UPF1 localization to CBs, for UPF1-UPF2 and UPF1-MVH interactions. Upon removal of TDRD6, the association of several mRNAs with UPF1 and UPF2 is disturbed, and the long 3' UTR-stimulated but not the downstream exon-exon junction triggered pathway of NMD is impaired. Reduced association of the long 3' UTR mRNAs with UPF1 and UPF2 correlates with increased stability and enhanced translational activity. Thus, we identified TDRD6 within CBs as required for mRNA degradation, specifically the extended 3' UTR-triggered NMD pathway, and provide evidence for the requirement of NMD in spermiogenesis. This function depends on TDRD6-promoted assembly of mRNA and decay enzymes in CBs
-
Chromatoid Body Protein TDRD6 Supports Long 3’ UTR Triggered Nonsense Mediated mRNA Decay
2016Co-Authors: Grigorios Fanourgakis, Muge Akpinar, Mathias Lesche, Andreas Dahl, Rolf JessbergerAbstract:Chromatoid bodies (CBs) are spermiogenesis-specific organelles of largely unknown function. CBs harbor various RNA species, RNA-associated proteins and proteins of the tudor domain family like TDRD6, which is required for a proper CB architecture. Proteome analysis of purified CBs revealed components of the nonsense-mediated mRNA decay (NMD) machinery including UPF1. TDRD6 is essential for UPF1 localization to CBs, for UPF1-UPF2 and UPF1-MVH interactions. Upon removal of TDRD6, the association of several mRNAs with UPF1 and UPF2 is disturbed, and the long 3’ UTR-stimulated but not the downstream exon-exon junction triggered pathway of NMD is impaired. Reduced association of the long 3’ UTR mRNAs with UPF1 and UPF2 correlates with increased stability and enhanced translational activity. Thus, we identified TDRD6 within CBs as required for mRNA degradation, specifically the extended 3’ UTR-triggered NMD pathway, and provide evidence for the requirement of NMD in spermiogenesis. This function depends on TDRD6-promoted assembly of mRNA and decay enzymes in CBs.