cloning and characterisation of vegetal pole specific genes in Xenopus laevis

by Clare Hudson

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Published: Pages: 163 Downloads: 568
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Thesis (Ph.D.) - University of Warwick, 1997.

StatementClare Hudson.
The Physical Object
Pagination163p. 22 ap.p.endix p.ages
Number of Pages163
ID Numbers
Open LibraryOL22431335M

Abstract Mammalian forms of the transcription repressor, Kaiso, can reportedly bind methylated DNA and non-methylated CTGCNA we compare the DNA-binding properties of Kaiso from frog, fish and chicken and demonstrate that only the methyl-CpG-binding function of Kaiso is evolutionarily conserved. We present several independent experimental lines of evidence that the phenotypic. We report that Vg1, a maternal mRNA localized to the vegetal hemisphere of frog eggs, encodes a member of the transforming growth factor-β (TGF-β) family of proteins. Furthermore, we show that Vg1 mRNA is distributed to presumptive endodermal cells after fertilization. Previous studies had shown that the vegetal end of a frog egg produces a signal that induces the overlying animal pole cells. Abstract ZFP36 constitutes a small family of RNA binding proteins (formerly known as the TIS11 family) that target mRNA and promote their degradation. In mammals, ZFP36 proteins are encoded by four genes and, although they show similar activities in a cellular RNA destabilization assay, there is still a limited knowledge of their mRNA targets and it is not known whether or not they have. (C–E) ntlexpression at the shield stage (C, lateral view), at the 90% epiboly stage (D, vegetal pole view), and at the Expression cloning of Siamois, a Xenopus homeobox gene expressed in dorsal–vegetal cells of blastulae Tates and roles of the presumptive organizer region in the cell embryo in normal development of Xenopus laevis.

Brachyury is the founder member of the T-box family of transcription factors, which is characterized by a DNA-binding domain of approximately amino acids. Members of the T-box gene family play important roles in the development of both vertebrate and invertebrate embryos, including the control of gastrulation, development of the heart, and perhaps even the decision as to whether to form. In the frog model organism, Xenopus laevis, asymmetry in the oocyte is readily apparent prior to egg fertilization, with a darkly pigmented animal pole housing the nucleus and a pale vegetal pole enriched with yolk proteins. This animal-vegetal axis roughly corresponds to the . Abstract Eggs of Xenopus laevis undergo a postfertilization cortical rotation that specifies the position of the dorso-ventral axis and activates a transplantable dorsal-determining activity in dorsal blastomeres by the cell have heretofore been no reported dorso-ventral asymmetries in endogenous signaling proteins that may be involved in this dorsal-determining activity during. During vertebrate embryogenesis, precise regulation of gene expression is crucial for proper cell fate determination. Much of what we know about vertebrate development has been gleaned from experiments performed on embryos of the amphibian Xenopus laevis; this review will focus primarily on studies of this model organism. An early critical step during vertebrate development is the formation of.

We identified a novel cDNA, XCL‐2, encoding an m‐type calpain, a calcium‐dependent intracellular protease. This protein has all characteristic structures and active sites of canonical calpains. Zygot.   While X. tropicalis is diploid, with two copies of each gene on 10 pairs of chromosomes, the X. laevis genome has undergone duplication and could have four copies of every gene on 18 pairs of chromosomes. Sequencing X. laevis would have been not only more costly, but also harder, because of the difficulty of matching genes to the proper chromosome. This review aims to propose an integrated model for dorsal‐ventral and anterior‐posterior development of ized Xenopus eggs contain two determinants, a vegetal half endomesodermal determinant and a vegetal pole dorsal determinant (DD). The organizer forms in the specific intersection of the determinants, in a cell‐autonomous manner. Asymmetric distribution of biomolecules of maternal origin in the Xenopus laevis egg and their impact on the developmental plan. Sindelka R, Abaffy P, Qu Y, Tomankova S, Sidova M, Naraine R, Kolar M, Peuchen E, Sun L, Dovichi N, Kubista M. Sindelka R, et al. Sci Rep. May 29;8(1) doi: /s

cloning and characterisation of vegetal pole specific genes in Xenopus laevis by Clare Hudson Download PDF EPUB FB2

A full length Cloning and characterisation of vegetal pole specific genes in Xenopus laevis book laevis osteocalcin (bone Gla protein, BGP) has been cloned by a combination of reverse transcription and amplification by the polymerase chain reaction, sequenced, and found to encode a polypeptide with amino acid residues, including a residue prepro-region and a residue mature protein.

The N-terminal region of the mature Xenopus BGP (xBGP), as deduced Cited by:   Cloning of Tbx6 from Xenopus laevis. We searched for new T‐box genes from Xenopus laevis and performed PCR from gastrula cDNA using degenerate primers. The fragments obtained were heterogeneous in length, spanning approximately – bp These fragments were cloned into pBluescript II KS(–) vector and several clones were by: The cloning and characterisation of vegetal pole specific genes in Xenopus laevis.

(Thesis) Hudson C. Publisher: University of Warwick [] Metadata Source: The British Library Type: Thesis. Abstract. No abstract supplied. Menu. Formats. Abstract. EThOS. About. About Europe PMC; Funders Author: Hudson C.

Cloning and characterization of the T-box gene Tbx6 in Xenopus laevis Article in Development Growth and Regeneration 43(6) February with 46 Reads How we measure 'reads'. This is a promising approach for characterization of novel gene transcripts from EST libraries and has recently been used to identify ovary specific genes in zebrafish [44] and rainbow trout [   We have cloned a cDNA (xlan4) from a Xenopus laevis oocyte cDNA library whose cognate mRNA is localized in the animal pole region of full grown oocytes.

The cDNA can be translated in vitro to produce a predicted size protein of 35 kDa and, is also expressed in E. coli as a fusion protein. The conceptual protein encoded by the xlan4 cDNA is % proline rich and possesses several.

Expression cloning requires a representative cDNA or genomic DNA library and a host organism in which the cloned genes can be transcribed and/or translated. It likewise requires a method to detect the expressed protein using, for example, the inherent biological activity of the gene or antibodies specific for the gene product.

PhD title: The cloning and characterisation of vegetal pole specific genes in Xenopus laevis. Publications A Simple Method to Identify Ascidian Brain Lineage Cells at.

1. Introduction. drg gene was identified by subtractive cDNA cloning as a gene highly expressed in mouse embryonic brain (Kumar et al., ).The developmentally regulated GTP-binding protein (DRG) has G-motifs that are known to constitute the core of the GTPase domain, although only GTP-binding activity has been shown for DRG Sazuka et al.,Sommer et al.,   Recent studies have suggested that localized maternal components in the vegetal hemisphere are involved in activating muscle-specific actin genes in embryonic mesoderm (Gurdon et al., ).

Finally, many experiments suggest that vegetal determinants play a critical role in the formation of the dorsal-ventral axis of the embryo (Gerhart et al.

1. Cloning and expression pattern of Xsap Several genes encoding ETS transcription factors have been isolated in Xenopus laevis: e.g. Xfli (Meyer et al., ), Xets-1/Xets-2 (Meyer et al., ), Xer81 (Muenchberg and Steinbeisser,Chen et al., ) and Xerg (Baltzinger et al., ).Genes encoding ETS proteins of the TCF (ternary complex factor) subfamily have been.

A Xenopus gene whose expression can be activated by the organizer-specific homeobox genes goosecoid and Xnot2 was isolated by differential screening. The chordin gene encodes a novel protein of amino acids that has a signal sequence and four Cys-rich domains. The expression of chordin starts in Spemann’s organizer subsequent to that of goosecoid, and its induction by activin.

Introduction. Xenopus laevis (Xl) oocytes are the best characterized model for maturation and other oocytes, XI oocytes are asymmetric cells with a complex internal polarity. On one side, the dark animal pole contains the nucleus, the endoplasmic reticulum (ER) and pigmented granules ; on the other side, the germ plasm and a mitochondrial cloud are distributed evenly in the.

The cloning and characterisation of vegetal pole specific genes in Xenopus laevis. Author: Hudson, Clare. ISNI: Awarding Body: University of Warwick Current Institution: University of Warwick Date of Award: Availability of Full Text.

Xenopus organizer specific gene Noggin possesses nearly all the characterestic properties of the action of organizer to specify the embryonic body axis.

To analyze how the maternal inherited. (A) RT-PCR analysis of Xhmg-at-hook and ODC transcription during Xenopus laevis development. Numbers refer to embryo stages. (B–G) Results of WISH on Xenopus laevis embryos. (B–B’) Stage 2: Xhmg-at-hook maternal transcripts are localised in the animal pole (ap).

(C) Stage faint staining is detectable in both the developing eye (white. narily conserved and thus make animals such as Xenopus laevis a suitable model system to further analyze MGP gene expression. In this report we present the cloning and organization of the MGP gene from X.

laevis and the functional characterization of its 5¢ promoter region. In transient transfection experiments using different deletion. Abstract We have performed an expression cloning screen in Xenopus laevis with the aim of isolating novel gene activities from the neural plate.

Of 8, clones screened, we isolated 61 clones that. Vegetal pole explants from blastula stage Xenopus embryos, which are specified to become endoderm, autonomously express endodermal markers in the absence of mesoderm (Gamer and Wright, ; Henry et al., ).

In agreement with previous studies, these explants fail to differentiate into histologically identifiable structures. In Xenopus laevis, factors secreted from the vegetal pole induce mesoderm in the adjacent marginal zone; members of both the transforming growth factor-beta (TGF-beta) and fibroblast growth factor.

Gurdon JB, Fairman S, Mohun TJ, Brennan S. Activation of muscle-specific actin genes in Xenopus development by an induction between animal and vegetal cells of a blastula.

Cell. Jul; 41 (3)– Heasman J, Wylie CC, Hausen P, Smith JC. Fates and states of determination of single vegetal pole blastomeres of X. laevis. Cell. A vector-based RNAi expression system was developed using the Xenopus tropicalis U6 promoter, which transcribes small RNA genes by RNA polymerase III.

The system was first validated in a Xenopus. Expression cloning experiments in the African clawed frog Xenopus laevis have provided numerous insights into developmental mechanisms and have provided ways to identify genes that are involved in the process of neural induction and neural patterning.

Examples include the organizer-expressed BMP antagonists that are essential for neural induction, and modulators of the Wnt pathway, that are.

Cloning and analysing of 5′ flanking region of Xenopus organizer gene noggin Article (PDF Available) in Cell Research 9(3) October with 42 Reads How we measure 'reads'. Cloning and characterization of the Xenopus laevis p8 gene Toshime Igarashi,1 Hiroki Kuroda,1 Shuji Takahashi2 and Makoto Asashima 1,2* 1Department of Life Sciences (Biology) and 2CREST Project, Graduate School of Arts and Sciences, University of Tokyo.

We here report the cloning of the complete p2rx gene family in Xenopus in addition to p2rx4 and p2rx7 members previously identified (Juranka et al., ; Paukert et al., ). Moreover, we provide a complete expression map of all p2rx genes throughout X.

laevis embryonic life. This is the first study to compare the expression of the entire. Here I review progress in the collection of both sequence data and physical clone reagents for protein coding genes. I conclude that we have cDNA sequences for around 50% and full‐length clones for about 35% of the genes in Xenopus tropicalis, and similar numbers but a smaller proportion for Xenopus laevis.

In addition, I demonstrate that. Abstract We have performed an expression cloning screen in Xenopus laevis with the aim of isolating novel gene activities from the neural 8, clones screened, we isolated 61 clones that affected either neural plate patterning or tadpole morphology.

Of these, 20 clones encoded RNA binding proteins, and the majority of these are heterogeneous nuclear ribonucleoproteins (hnRNPs) or SR. Gene names should not start with any characters or words in order to identify the gene as being Xenopus (e.g.

X, Xt, Xl, Xenopus, tropicalis, laevis). Gene names are lower case and italics, and should only contain Latin letters and Arabic numbers. A central question in developmental biology is to explain how cells in different regions of an embryo acquire different developmental fates.

We have begun to address this question by investigating whether specific RNAs are localized within a frog egg. Differential screening of a cDNA library shows that most maternal RNAs are uniformly distributed along the animal-vegetal axis.

(). An mRNA localized to the vegetal cortex of Xenopus oocytes encodes a protein with a nanos-like zinc finger domain.

(). An ultrastructural and radioautographic study of early oogenesis in the toad Xenopus laevis. (). An ultrastructural study of primordial germ cells, oogonia and early oocytes in Xenopus laevis. (). Abstract. We have studied the organization of the histone genes in the DNA from several individuals of Xenopus laevis.

For that purpose, Southern blots of genomic DNA, that was digested with several restriction enzymes, were hybridized with radioactively labeled DNA fragments from clone X1-hi-1 (14), containing genes for Xenopus histones H2A, H2B, H3 and H4.We have cloned a cDNA encoding a novel polypeptide capable of inducing dorsal development in Xenopus embryos.

RNA transcripts from this clone rescue normal development when injected into ventralized embryos and result in excessive head development at high doses. Therefore, we have named the cDNA noggin.

noggin cDNA contains a single reading frame encoding a 26 kd protein with a .