Cloning and developmental expression patterns of Dlx2, Lhx7 and Lhx9 in the medaka fish (Oryzias latipes)

Identification and characterisation of differentially regulated genes in preimplantation human embryonic development are required to improve embryo quality and pregnancy rates in IVF. In this study, we examined expression of a number of genes known to be critical for early development and compared expression profiles in individual preimplantation human embryos to establish any differences in gene expression in fresh compared to frozen–thawed embryos used routinely in IVF. We analysed expression of 19 genes by cDNA amplification followed by quantitative real-time PCR in a panel of 44 fresh and frozen–thawed human preimplantation embryos. Fresh embryos were obtained from surplus early cleavage stage embryos and frozen–thawed embryos from cryopreserved 2PN embryos. Our aim was to determine differences in gene expression between fresh and frozen–thawed human embryos, but we also identified differences in developmental expression patterns for particular genes. We show that overall gene expression among embryos of the same stage is highly variable and our results indicate that expression levels between groups did differ and differences in expression of individual genes was detected. Our results show that gene expression from frozen–thawed embryos is more consistent when compared with fresh, suggesting that cryopreserved embryos may represent a reliable source for studying the molecular events underpinning early human embryo development.

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S-Phase Progression Mediates Activation of a Silenced Gene in Synthetic Nuclei

Molecular and Cellular Biology ◽

10.1128/mcb.20.11.4169-4180.2000 ◽

2000 ◽

Vol 20 (11) ◽

pp. 4169-4180 ◽

Cited By ~ 5

Author(s):

Alison J. Crowe ◽

Julie L. Piechan ◽

Ling Sang ◽

Michelle C. Barton

Keyword(s):

Dna Replication ◽

Developmental Stage ◽

Expression Patterns ◽

Marker Gene ◽

Nuclear Extract ◽

S Phase ◽

Developmental Expression ◽

Aberrant Expression ◽

Transcription Repressors

ABSTRACT Aberrant expression of developmentally silenced genes, characteristic of tumor cells and regenerating tissue, is highly correlated with increased cell proliferation. By modeling this process in vitro in synthetic nuclei, we find that DNA replication leads to deregulation of established developmental expression patterns. Chromatin assembly in the presence of adult mouse liver nuclear extract mediates developmental stage-specific silencing of the tumor marker gene alpha-fetoprotein (AFP). Replication of silenced AFP chromatin in synthetic nuclei depletes sequence-specific transcription repressors, thereby disrupting developmentally regulated repression. Hepatoma-derived factors can target partial derepression of AFP, but full transcription activation requires DNA replication. Thus, unscheduled entry into S phase directly mediates activation of a developmentally silenced gene by (i) depleting developmental stage-specific transcription repressors and (ii) facilitating binding of transactivators.

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Functional equivalence of the transcription factors Pax2 and Pax5 in mouse development

Development ◽

10.1242/dev.127.17.3703 ◽

2000 ◽

Vol 127 (17) ◽

pp. 3703-3713 ◽

Cited By ~ 5

Author(s):

M. Bouchard ◽

P. Pfeffer ◽

M. Busslinger

Keyword(s):

Transcription Factors ◽

Expression Patterns ◽

Brain Regions ◽

Vertebrate Evolution ◽

Developmental Expression ◽

Temporal Expression ◽

Mouse Development ◽

Highly Sensitive ◽

Organizing Center ◽

Cerebellum Development

Pax2 and Pax5 arose by gene duplication at the onset of vertebrate evolution and have since diverged in their developmental expression patterns. They are expressed in different organs of the mouse embryo except for their coexpression at the midbrain-hindbrain boundary (MHB), which functions as an organizing center to control midbrain and cerebellum development. During MHB development, Pax2 expression is initiated prior to Pax5 transcription, and Pax2(−/−) embryos fail to generate the posterior midbrain and cerebellum, whereas Pax5(−/−) mice exhibit only minor patterning defects in the same brain regions. To investigate whether these contrasting phenotypes are caused by differences in the temporal expression or biochemical activity of these two transcription factors, we have generated a knock-in (ki) mouse, which expresses a Pax5 minigene under the control of the Pax2 locus. Midbrain and cerebellum development was entirely rescued in Pax2(5ki/5ki) embryos. Pax5 could furthermore completely substitute for the Pax2 function during morphogenesis of the inner ear and genital tracts, despite the fact that the Pax5 transcript of the Pax2(5ki)allele was expressed only at a fivefold lower level than the wild-type Pax2 mRNA. As a consequence, the Pax2(5ki)allele was able to rescue most but not all Pax2 mutant defects in the developing eye and kidney, both of which are known to be highly sensitive to Pax2 protein dosage. Together these data demonstrate that the transcription factors Pax2 and Pax5 have maintained equivalent biochemical functions since their divergence early in vertebrate evolution.

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trkC, a receptor for neurotrophin-3, is widely expressed in the developing nervous system and in non-neuronal tissues

Development ◽

10.1242/dev.118.2.463 ◽

1993 ◽

Vol 118 (2) ◽

pp. 463-475 ◽

Cited By ~ 26

Author(s):

L. Tessarollo ◽

P. Tsoulfas ◽

D. Martin-Zanca ◽

D.J. Gilbert ◽

N.A. Jenkins ◽

...

Keyword(s):

Nerve Growth Factor ◽

Growth Factor ◽

Tyrosine Kinases ◽

Expression Patterns ◽

Developmental Expression ◽

Receptor System ◽

Nerve Growth ◽

Trk Receptor ◽

Neurotrophin 3 ◽

Neuronal Tissues

The Trk family of tyrosine kinases encodes receptors for nerve growth factor-related neurotrophins. Here we present a developmental expression study of trkC, which encodes a receptor for neurotrophin-3 (NT-3). Like the related genes, trk and trkB, trkC is expressed primarily in neural lineages although the pattern is complex and includes non-neuronal cells. Direct comparison with trk and trkB developmental expression patterns permits the following observations. (1) trkC is expressed in novel neural tissues where other Trk genes are silent. (2) Some tissues appear to coexpress trkB and trkC receptors in the embryo and in the adult. (3) trkC expression can be detected in the gastrulating embryo. These data provide insights into the role of Trk-family receptors and nerve growth factor-related neurotrophins during development and suggest that, in addition to regulating neuronal survival and differentiation, the neurotrophin/Trk receptor system may have broader physiological effects. Finally, interspecific mouse backcrosses have been used to map the location of each of the Trk genes on mouse chromosomes. Alignment with available chromosomal maps identify possible linkage between the Trk genes and known neurological mutations.

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Characterization of an amphioxus paired box gene, AmphiPax2/5/8: developmental expression patterns in optic support cells, nephridium, thyroid-like structures and pharyngeal gill slits, but not in the midbrain-hindbrain boundary region

Development ◽

10.1242/dev.126.6.1295 ◽

1999 ◽

Vol 126 (6) ◽

pp. 1295-1304 ◽

Cited By ~ 10

Author(s):

Z. Kozmik ◽

N.D. Holland ◽

A. Kalousova ◽

J. Paces ◽

M. Schubert ◽

...

Keyword(s):

Gene Expression ◽

Central Nervous System ◽

Nervous System ◽

Expression Patterns ◽

Boundary Region ◽

Developmental Expression ◽

Developmental Gene Expression ◽

Expression Evidence ◽

Engrailed Genes ◽

Otic Vesicles

On the basis of developmental gene expression, the vertebrate central nervous system comprises: a forebrain plus anterior midbrain, a midbrain-hindbrain boundary region (MHB) having organizer properties, and a rhombospinal domain. The vertebrate MHB is characterized by position, by organizer properties and by being the early site of action of Wnt1 and engrailed genes, and of genes of the Pax2/5/8 subfamily. Wada and others (Wada, H., Saiga, H., Satoh, N. and Holland, P. W. H. (1998) Development 125, 1113–1122) suggested that ascidian tunicates have a vertebrate-like MHB on the basis of ascidian Pax258 expression there. In another invertebrate chordate, amphioxus, comparable gene expression evidence for a vertebrate-like MHB is lacking. We, therefore, isolated and characterized AmphiPax2/5/8, the sole member of this subfamily in amphioxus. AmphiPax2/5/8 is initially expressed well back in the rhombospinal domain and not where a MHB would be expected. In contrast, most of the other expression domains of AmphiPax2/5/8 correspond to expression domains of vertebrate Pax2, Pax5 and Pax8 in structures that are probably homologous - support cells of the eye, nephridium, thyroid-like structures and pharyngeal gill slits; although AmphiPax2/5/8 is not transcribed in any structures that could be interpreted as homologues of vertebrate otic placodes or otic vesicles. In sum, the developmental expression of AmphiPax2/5/8 indicates that the amphioxus central nervous system lacks a MHB resembling the vertebrate isthmic region. Additional gene expression data for the developing ascidian and amphioxus nervous systems would help determine whether a MHB is a basal chordate character secondarily lost in amphioxus. The alternative is that the MHB is a vertebrate innovation.

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Localization and Developmental Expression Patterns of CSPG in the RCS Rat Retina

i-Perception ◽

10.1068/ic218 ◽

2011 ◽

Vol 2 (4) ◽

pp. 218-218

Author(s):

Li-Feng Chen ◽

Jian-Rong He

Keyword(s):

Expression Patterns ◽

Developmental Expression ◽

Rat Retina ◽

Rcs Rat

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Fluorescent Light Incites a Conserved Immune and Inflammatory Genetic Response within Vertebrate Organs (Danio Rerio, Oryzias Latipes and Mus Musculus)

Genes ◽

10.3390/genes10040271 ◽

2019 ◽

Vol 10 (4) ◽

pp. 271 ◽

Cited By ~ 2

Author(s):

Boswell ◽

Lu ◽

Boswell ◽

Savage ◽

Hildreth ◽

...

Keyword(s):

Immune Responses ◽

Danio Rerio ◽

Mus Musculus ◽

Expression Patterns ◽

Solar Spectrum ◽

Oryzias Latipes ◽

Hairless Mouse ◽

Gene Clustering ◽

Fluorescent Light ◽

Evolutionary Divergence

Fluorescent light (FL) has been utilized for ≈60 years and has become a common artificial light source under which animals, including humans, spend increasing amounts of time. Although the solar spectrum is quite dissimilar in both wavelengths and intensities, the genetic consequences of FL exposure have not been investigated. Herein, we present comparative RNA-Seq results that establish expression patterns within skin, brain, and liver for Danio rerio, Oryzias latipes, and the hairless mouse (Mus musculus) after exposure to FL. These animals represent diurnal and nocturnal lifestyles, and ≈450 million years of evolutionary divergence. In all three organisms, FL induced transcriptional changes of the acute phase response signaling pathway and modulated inflammation and innate immune responses. Our pathway and gene clustering analyses suggest cellular perception of oxidative stress is promoting induction of primary up-stream regulators IL1B and TNF. The skin and brain of the three animals as well as the liver of both fish models all exhibit increased inflammation and immune responses; however, the mouse liver suppressed the same pathways. Overall, the conserved nature of the genetic responses observed after FL exposure, among fishes and a mammal, suggest the presence of light responsive genetic circuitry deeply embedded in the vertebrate genome.

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