Xenopus Distal-less related homeobox genes are expressed in the developing forebrain and are induced by planar signals

Development ◽  
1993 ◽  
Vol 117 (3) ◽  
pp. 961-975 ◽  
Author(s):  
N. Papalopulu ◽  
C. Kintner
Keyword(s):  
In Situ Hybridization ◽  
Neural Plate ◽  
Cdna Clones ◽  
Rnase Protection ◽  
Early Expression ◽  
Neural Ectoderm ◽  
Polymerase Chain ◽  
Sequence Similarities ◽  
Anterior Neural Plate

The polymerase chain reaction (PCR) was used to isolated five Xenopus homeobox clones (X-dll1 to 5) that are related to the Drosophila Distal-less (Dll) gene and we propose a subdivision of the vertebrate distal-less gene family according to sequence similarities. cDNA clones were isolated for X-dll2, 3 and 4, and their expression was studied by RNase protection and in situ hybridization. X-dll2, which belongs to a separate subfamily than X-dll3 and 4, is not expressed in the neural ectoderm. X-dll3 and X-dll4, which belong to the same subfamily, have a similar but not identical pattern of expression that is restricted to anterior ectodermal derivatives, namely the ventral forebrain, the cranial neural crest and the cement gland. X-dll3 is also expressed in the olfactory and otic placodes while X-dll4 is expressed in the developing eye. X-dll3 differs from the other Xenopus genes and the previously isolated Dll-related mouse genes, in that localized expression can be detected by in situ hybridization very early in development, in the anterior-transverse ridge of the open neural plate. Based on that early expression pattern, we suggest that X-dll3 marks the rostral-most part of the neural plate, which gives rise to the ventral forebrain. Finally, we have used these Xenopus distal-less genes to show that the anterior neural plate can be induced by signals that spread within the plane of neural ectoderm, indicating that at least the initial steps of forebrain development do not require signals from underlying mesoderm.

Expression of Xenopus N-CAM RNA in ectoderm is an early response to neural induction

Development ◽  
1987 ◽  
Vol 99 (3) ◽  
pp. 311-325 ◽  
Author(s):  
C.R. Kintner ◽  
D.A. Melton
Keyword(s):  
Neural Development ◽  
Transcriptional Activation ◽  
Neural Induction ◽  
Early Response ◽  
Neural Plate ◽  
Cdna Clones ◽  
Epidermal Tissue ◽  
Early Expression ◽  
Neural Ectoderm

We have isolated Xenopus laevis N-CAM cDNA clones and used these to study the expression of N-CAM RNA during neural induction. The results show that the first marked increase in N-CAM RNA levels occurs during gastrulation when mesoderm comes in contact with ectoderm and induces neural development. In situ hybridization results show that the early expression of N-CAM RNA is localized to the neural plate and its later expression is confined to the neural tube. Induction experiments with explanted germ layers show that N-CAM RNA is not expressed in ectoderm unless there is contact with inducing tissue. Together these results suggest an approach to studying how ectoderm is committed to form neural rather than epidermal tissue. Specifically, the data suggest that neural commitment is marked and perhaps mediated by the transcriptional activation of genes, like N-CAM, in the neural ectoderm.

Human papilloma virus detection in liquid cytology, in situ hybridization and polymerase chain reaction

2005 ◽  
Vol 446 (2) ◽  
pp. 202-203 ◽  
Author(s):  
F. Alameda ◽  
L. Pijuan ◽  
L. Ferrer ◽  
M. L. Mari�oso ◽  
M. Muset ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
In Situ Hybridization ◽  
Human Papilloma Virus ◽  
Virus Detection ◽  
Chain Reaction ◽  
Papilloma Virus ◽  
Polymerase Chain

Analysis of Hox-4.5 and Hox-3.6 expression during newt limb regeneration: differential regulation of paralogous Hox genes suggest different roles for members of different Hox clusters

Development ◽  
1993 ◽  
Vol 117 (4) ◽  
pp. 1397-1407 ◽  
Author(s):  
H.G. Simon ◽  
C.J. Tabin
Keyword(s):  
Hox Genes ◽  
Limb Regeneration ◽  
Differential Regulation ◽  
Epithelial Tissue ◽  
Cdna Clones ◽  
Rnase Protection ◽  
Adult Kidney ◽  
Early Expression ◽  
Hox Clusters ◽  
Newt Limb

Adult urodele amphibians can regenerate their limbs and tail. Based on their roles in other developing systems, Hox genes are strong candidates for genes that play a role in regulating pattern formation during regeneration. There are four homologous clusters of Hox genes in vertebrate genomes. We isolated cDNA clones of two newt homeobox genes from homologous positions within two Hox clusters; Hox-4.5 and Hox-3.6. We used RNase protection on nonamputated (normal) and regenerating newt appendages and tissue to compare their transcriptional patterns. Both genes show increased expression upon amputation with similar kinetics. Hox-4.5 and Hox-3.6 transcription is limited to the mesenchymal cells in the regenerates and is not found in the epithelial tissue. In addition to regenerating appendages, both genes are transcriptionally active in adult kidney of the newt. Striking differences were found in the regulation of Hox-4.5 and Hox-3.6 when they were compared in unamputated limbs and in regenerating forelimbs versus regenerating hindlimbs. Hox-4.5 is expressed in the blastema of regenerating fore- and hindlimbs, but Hox-4.5 transcripts are not detectable in normal limbs. In contrast, Hox-3.6 transcripts are found exclusively in posterior appendages, but are present in normal as well as regenerating hindlimbs and tails. Hox-4.5 is also expressed at a higher level in proximal (mid-humerus) regenerates than in distal ones (mid-radius). When we proximalized the positional memory of a distal blastema with retinoic acid, we find that the early expression level of Hox-4.5 is also proximalized. When the expression of these genes is compared to the expression of two previously reported newt Hox genes, a consistent pattern emerges, which can be interpreted in terms of differential roles for the different Hox clusters in determining regenerative limb morphology.

scholarly journals Epstein-Barr virus-associated gastric carcinoma in Brazil: comparison between in situ hybridization and polymerase chain reaction detection

2012 ◽  
Vol 43 (1) ◽  
pp. 393-404 ◽  
Author(s):  
Marcos Antonio Pereira de Lima ◽  
Márcia Valéria Pitombeira Ferreira ◽  
Marcos Aurélio Pessoa Barros ◽  
Maria Inês de Moura Campos Pardini ◽  
Adriana Camargo Ferrasi ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
In Situ Hybridization ◽  
Gastric Carcinoma ◽  
Epstein Barr Virus ◽  
Polymerase Chain Reaction Detection ◽  
Chain Reaction ◽  
Barr Virus ◽  
Polymerase Chain ◽  
Epstein Barr

Expression of the mRNAs for the Kv3.1 potassium channel gene in the adult and developing rat brain

1992 ◽  
Vol 68 (3) ◽  
pp. 756-766 ◽  
Author(s):  
T. M. Perney ◽  
J. Marshall ◽  
K. A. Martin ◽  
S. Hockfield ◽  
L. K. Kaczmarek
Keyword(s):  
In Situ Hybridization ◽  
Rat Brain ◽  
K Channel ◽  
Rnase Protection ◽  
Hybridization Histochemistry ◽  
Adult Rat ◽  
In Situ Hybridization Histochemistry ◽  
Adult Rat Brain ◽  
Developing Rat

1. The gene for a mammalian Shaw K+ channel has recently been cloned and has been shown, by alternative splicing, to give rise to two different transcripts, Kv3.1 alpha and Kv3.1 beta. To determine whether these channels are associated with specific types of neurons and to determine whether or not the alternately spliced K+ channel variants are differentially expressed, we used ribonuclease (RNase) protection assays and in situ hybridization histochemistry to localize the specific subsets of neurons containing Kv3.1 alpha and Kv3.1 beta mRNAs in the adult and developing rat brain. 2. In situ hybridization histochemistry revealed a heterogeneous expression pattern of Kv3.1 alpha mRNA in the adult rat brain. Highest Kv3.1 alpha mRNA levels were expressed in the cerebellum. High levels of hybridization were also detected in the globus pallidus, subthalamus, and substantia nigra reticulata. Many thalamic nuclei, but in particular the reticular thalamic nucleus, hybridized well to Kv3.1 alpha-specific probes. A subpopulation of cells in the cortex and hippocampus, which by their distribution and number may represent interneurons, were also found to contain high levels of Kv3.1 alpha mRNA. In the brain stem, many nuclei, including the inferior colliculus and the cochlear and vestibular nuclei, also express Kv3.1 alpha mRNA. Low or undetectable levels of Kv3.1 alpha mRNA were found in the caudate-putamen, olfactory tubercle, amygdala, and hypothalamus. 3. Kv3.1 beta mRNA was also detected in the adult rat brain by both RNase protection assays and by in situ hybridization experiments. Although the beta splice variant is expressed at lower levels than the alpha species, the overall expression pattern for both mRNAs is similar, indicating that both splice variants co-expressed in the same neurons. 4. The expression of Kv3.1 alpha and Kv3.1 beta transcripts was examined throughout development. Kv3.1 alpha mRNA is detected as early as embryonic day 17 and then increases gradually until approximately postnatal day 10, when there is a large increase in the amount of Kv3.1 alpha mRNA. Interestingly, the expression of Kv3.1 beta mRNA only increases gradually during the developmental time frame examined. Densitometric measurements indicated that Kv3.1 alpha is the predominant splice variant found in neurons of the adult brain, whereas Kv3.1 beta appears to be the predominant species in embryonic and perinatal neurons. 5. Most of the neurons that express the Kv3.1 transcripts have been characterized electrophysiologically to have narrow action potentials and display high-frequency firing rates with little or no spike adaptation.(ABSTRACT TRUNCATED AT 400 WORDS)

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