A Xenopus DAZ-like gene encodes an RNA component of germ plasm and is a functional homologue of Drosophila boule

Development ◽  
1998 ◽  
Vol 125 (2) ◽  
pp. 171-180 ◽  
Author(s):  
D.W. Houston ◽  
J. Zhang ◽  
J.Z. Maines ◽  
S.A. Wasserman ◽  
M.L. King
Keyword(s):  
Cell Division ◽  
Germ Plasm ◽  
Rna Binding ◽  
Primordial Germ Cell ◽  
Early Embryo ◽  
Meiotic Cell ◽  
Binding Function ◽  
Germ Cell Specification ◽  
Mitochondrial Cloud

We have identified a localized RNA component of Xenopus germ plasm. This RNA, Xdazl (Xenopus DAZ-like), encodes a protein homologous to human DAZ (Deleted in Azoospermia), vertebrate DAZL and Drosophila Boule proteins. Human males deficient in DAZ have few or no sperm and boule mutant flies exhibit complete azoospermia and male sterility. Xdazl RNA was detected in the mitochondrial cloud and vegetal cortex of oocytes. In early embryos, the RNA was localized exclusively in the germ plasm. Consistent with other organisms, Xdazl RNA was also expressed in the spermatogonia and spermatocytes of frog testis. Proteins in the DAZ-family contain a conserved RNP domain implying an RNA-binding function. We have shown that Xdazl can function in vitro as an RNA-binding protein. To determine if the function of Xdazl in spermatogenesis was conserved, we introduced the Xdazl cDNA into boule flies. This resulted in rescue of the boule meiotic entry phenotype, including formation of spindles, phosphorylation of histone H3 and completion of meiotic cell division. Overall, these results suggest that Xdazl may be important for primordial germ cell specification in the early embryo and may play a role analogous to Boule in promoting meiotic cell division.

scholarly journals Patterns of localization and cytoskeletal association of two vegetally localized RNAs, Vg1 and Xcat-2

Development ◽  
1995 ◽  
Vol 121 (1) ◽  
pp. 201-208 ◽  
Author(s):  
C. Forristall ◽  
M. Pondel ◽  
L. Chen ◽  
M.L. King
Keyword(s):  
Germ Plasm ◽  
Rna Binding ◽  
Stage Iv ◽  
Rna Localization ◽  
Insoluble Fraction ◽  
Early Embryo ◽  
Vegetal Cortex ◽  
Cytoskeletal Component ◽  
Rare Class ◽  
Mitochondrial Cloud

In Xenopus, localization of a rare class of mRNAs during oogenesis is believed to initiate pattern formation in the early embryo. We have determined the pattern of RNA localization for one of these RNAs, Xcat-2, which encodes a putative RNA-binding protein related to Drosophila nanos (Mosquera, L., Forristall, C., Zhou, Y. and King, M. L. (1993) Development 117, 377–386). Xcat-2 is exclusively localized to the mitochondrial cloud in stage I oocytes, moves with this body into the vegetal cortex during stage II and, later, partitions into islands consistent with it being a component of the germ plasm. As previously shown, Vg1 is not localized to the vegetal cortex until stage IV and distributes to all vegetal blastomeres during development. We found a direct correlation between the localized condition of these RNAs and their recovery in a detergent-insoluble fraction. We present evidence suggesting that differential RNA binding to a cytoskeletal component(s) in the vegetal cortex determines the pattern of inheritance for that RNA in the embryo.

A critical role for Xdazl, a germ plasm-localized RNA, in the differentiation of primordial germ cells in Xenopus

Development ◽  
2000 ◽  
Vol 127 (3) ◽  
pp. 447-456 ◽  
Author(s):  
D.W. Houston ◽  
M.L. King
Keyword(s):  
Cell Division ◽  
Germ Cells ◽  
Germ Plasm ◽  
Rna Binding ◽  
Binding Protein ◽  
Primordial Germ Cells ◽  
Critical Role ◽  
Rna Binding Protein ◽  
Meiotic Cell ◽  
Dorsal Mesentery

Xdazl is an RNA component of Xenopus germ plasm and encodes an RNA-binding protein that can act as a functional homologue of Drosophila boule. boule is required for entry into meiotic cell division during fly spermatogenesis. Both Xdazl and boule are related to the human DAZ and DAZL, and murine Dazl genes, which are also involved in gamete differentiation. As suggested from its germ plasm localization, we show here that Xdazl is critically involved in PGC development in Xenopus. Xdazl protein is expressed in the cytoplasm, specifically in the germ plasm, from blastula to early tailbud stages. Specific depletion of maternal Xdazl RNA results in tadpoles lacking, or severely deficient in, primordial germ cells (PGCs). In the absence of Xdazl, PGCs do not successfully migrate from the ventral to the dorsal endoderm and do not reach the dorsal mesentery. Germ plasm aggregation and intracellular movements are normal indicating that the defect occurs after PGC formation. We propose that Xdazl is required for early PGC differentiation and is indirectly necessary for the migration of PGCs through the endoderm. As an RNA-binding protein, Xdazl may regulate translation or expression of factors that mediate migration of PGCs.

scholarly journals Single cell RNA-seq reveals genes vital to in vitro fertilized embryos and parthenotes in pigs

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zhi-Qiang Du ◽  
Hao Liang ◽  
Xiao-Man Liu ◽  
Yun-Hua Liu ◽  
Chonglong Wang ◽  
...  
Keyword(s):  
Embryo Development ◽  
Gene Networks ◽  
Regulatory Networks ◽  
Rna Binding ◽  
Expression Patterns ◽  
Early Embryo ◽  
Specific Factor ◽  
Early Embryos ◽  
Genome Activation

AbstractSuccessful early embryo development requires the correct reprogramming and configuration of gene networks by the timely and faithful execution of zygotic genome activation (ZGA). However, the regulatory principle of molecular elements and circuits fundamental to embryo development remains largely obscure. Here, we profiled the transcriptomes of single zygotes and blastomeres, obtained from in vitro fertilized (IVF) or parthenogenetically activated (PA) porcine early embryos (1- to 8-cell), focusing on the gene expression dynamics and regulatory networks associated with maternal-to-zygote transition (MZT) (mainly maternal RNA clearance and ZGA). We found that minor and major ZGAs occur at 1-cell and 4-cell stages for both IVF and PA embryos, respectively. Maternal RNAs gradually decay from 1- to 8-cell embryos. Top abundantly expressed genes (CDV3, PCNA, CDR1, YWHAE, DNMT1, IGF2BP3, ARMC1, BTG4, UHRF2 and gametocyte-specific factor 1-like) in both IVF and PA early embryos identified are of vital roles for embryo development. Differentially expressed genes within IVF groups are different from that within PA groups, indicating bi-parental and maternal-only embryos have specific sets of mRNAs distinctly decayed and activated. Pathways enriched from DEGs showed that RNA associated pathways (RNA binding, processing, transport and degradation) could be important. Moreover, mitochondrial RNAs are found to be actively transcribed, showing dynamic expression patterns, and for DNA/H3K4 methylation and transcription factors as well. Taken together, our findings provide an important resource to investigate further the epigenetic and genome regulation of MZT events in early embryos of pigs.

Genital ridges exert long-range effects on mouse primordial germ cell numbers and direction of migration in culture

Development ◽  
1990 ◽  
Vol 108 (2) ◽  
pp. 357-363 ◽  
Author(s):  
I. Godin ◽  
C. Wylie ◽  
J. Heasman
Keyword(s):  
Long Range ◽  
Primordial Germ Cells ◽  
Primordial Germ Cell ◽  
Great Majority ◽  
Early Embryo ◽  
Extrinsic Factors ◽  
Alkaline Phosphatase Staining ◽  
Hind Gut ◽  
Feeder Cell Layers

The functional gametes of all vertebrates first arise in the early embryo as a migratory population of cells, the primordial germ cells (PGCs). These migrate to, and colonise, the genital ridges (GR) during the early organogenesis period, giving rise to the complete differentiating gonad. PGCs first become visible by alkaline phosphatase staining in the root of the developing allantois at 8.5 days post coitum (dpc). At 9.5 dpc they are found in the wall of the hind-gut and, during the following three days, they migrate along the hind-gut mesentery to the dorsal body wall, and then to the genital ridges. By 12.5 dpc, the great majority of PGCs have colonised the genital ridges. During this period the number of PGCs increases from less than 100 to approximately 4000. In a previous paper (Donovan et al. 1986), we showed that 10.5 dpc PGCs can be explanted from the hind-gut mesentery, and will spread and migrate on feeder cell layers. We showed also that the intrinsic ability of PGCs to spread and migrate changes as they colonise the genital ridges. In this paper, we examine extrinsic factors that control PGC behaviour in vitro. Using PGCs taken from 8.5 dpc embryos, at the beginning of their migratory phase, we show that culture medium conditioned by 10.5 dpc genital ridges causes an increase in the number of PGCs in these cultures. We also show that PGCs migrate towards 10.5 dpc genital ridges in preference to other explanted organs. These experiments show that genital ridges exert long-range effects on the migrating population of PGCs.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Resf1 supports embryonic stem cell self-renewal and effective germline entry

2021 ◽  
Author(s):  
Matus Vojtek ◽  
Ian Chambers
Keyword(s):  
Stem Cells ◽  
Germ Cell ◽  
Germ Line ◽  
Primordial Germ Cell ◽  
Embryonic Stem ◽  
Cell Specification ◽  
Self Renewal ◽  
Downstream Target ◽  
Germ Cell Specification

Retroelement silencing factor 1 (Resf1) interacts with the key regulators of mouse embryonic stem cells (ESCs) Oct4 and Nanog, and its absence results in sterility of mice. However, the function of Resf1 in ESCs and germ line specification is poorly understood. In this study, we used Resf1 knockout cell lines to determine the requirements of RESF1 for ESCs self-renewal and for in vitro specification of ESCs into primordial germ cell-like cells (PGCLCs). We found that deletion of Resf1 in ESCs cultured in serum and LIF reduces self-renewal potential whereas episomal expression of RESF1 has a modest positive effect on ESC self-renewal. In addition, RESF1 is not required for the capacity of NANOG and its downstream target ESRRB to drive self-renewal in the absence of LIF. However, Resf1 deletion reduces efficiency of PGCLC differentiation in vitro. These results identify Resf1 as a novel player in the regulation of pluripotent stem cells and germ cell specification.

scholarly journals Generation of Primordial Germ Cell-like Cells from iPSCs Derived from Turner Syndrome Patients

Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3099
Author(s):  
Aline Fernanda de Souza ◽  
Fabiana Fernandes Bressan ◽  
Naira Caroline Godoy Pieri ◽  
Ramon Cesar Botigelli ◽  
Tamas Revay ◽  
...  
Keyword(s):  
Germ Cell ◽  
Turner Syndrome ◽  
Genetic Disorder ◽  
Primordial Germ Cells ◽  
Primordial Germ Cell ◽  
Cell Formation ◽  
In Vitro Models ◽  
Germline Development ◽  
Germ Cell Specification

Turner syndrome (TS) is a genetic disorder in females with X Chromosome monosomy associated with highly variable clinical features, including premature primary gonadal failure leading to ovarian dysfunction and infertility. The mechanism of development of primordial germ cells (PGCs) and their connection with ovarian failure in TS is poorly understood. An in vitro model of PGCs from TS would be beneficial for investigating genetic and epigenetic factors that influence germ cell specification. Here we investigated the potential of reprogramming peripheral mononuclear blood cells from TS women (PBMCs-TS) into iPSCs following in vitro differentiation in hPGCLCs. All hiPSCs-TS lines demonstrated pluripotency state and were capable of differentiation into three embryonic layers (ectoderm, endoderm, and mesoderm). The PGCLCs-TS recapitulated the initial germline development period regarding transcripts and protein marks, including the epigenetic profile. Overall, our results highlighted the feasibility of producing in vitro models to help the understanding of the mechanisms associated with germ cell formation in TS.

scholarly journals Causes and evolutionary consequences of primordial germ-cell specification mode in metazoans

2017 ◽  
Vol 114 (23) ◽  
pp. 5784-5791 ◽  
Author(s):  
Carrie A. Whittle ◽  
Cassandra G. Extavour
Keyword(s):  
Germ Cells ◽  
Gene Networks ◽  
Evolutionary Biology ◽  
Large Scale ◽  
Germ Plasm ◽  
Germ Line ◽  
Primordial Germ Cell ◽  
Sequence Evolution ◽  
Animal Evolution ◽  
Germ Cell Specification

In animals, primordial germ cells (PGCs) give rise to the germ lines, the cell lineages that produce sperm and eggs. PGCs form in embryogenesis, typically by one of two modes: a likely ancestral mode wherein germ cells are induced during embryogenesis by cell–cell signaling (induction) or a derived mechanism whereby germ cells are specified by using germ plasm—that is, maternally specified germ-line determinants (inheritance). The causes of the shift to germ plasm for PGC specification in some animal clades remain largely unknown, but its repeated convergent evolution raises the question of whether it may result from or confer an innate selective advantage. It has been hypothesized that the acquisition of germ plasm confers enhanced evolvability, resulting from the release of selective constraint on somatic gene networks in embryogenesis, thus leading to acceleration of an organism’s protein-sequence evolution, particularly for genes expressed at early developmental stages, and resulting in high speciation rates in germ plasm-containing lineages (denoted herein as the “PGC-specification hypothesis”). Although that hypothesis, if supported, could have major implications for animal evolution, our recent large-scale coding-sequence analyses from vertebrates and invertebrates provided important examples of genera that do not support the hypothesis of liberated constraint under germ plasm. Here, we consider reasons why germ plasm might be neither a direct target of selection nor causally linked to accelerated animal evolution. We explore alternate scenarios that could explain the repeated evolution of germ plasm and propose potential consequences of the inheritance and induction modes to animal evolutionary biology.

scholarly journals Comparative Principles of DNA Methylation Reprogramming during Human and Mouse In Vitro Primordial Germ Cell Specification

2016 ◽  
Vol 39 (1) ◽  
pp. 104-115 ◽  
Author(s):  
Ferdinand von Meyenn ◽  
Rebecca V. Berrens ◽  
Simon Andrews ◽  
Fátima Santos ◽  
Amanda J. Collier ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Germ Cell ◽  
Primordial Germ Cell ◽  
Cell Specification ◽  
Germ Cell Specification ◽  
Human And Mouse
Sign in / Sign up

Export Citation Format

Share Document