scholarly journals 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
Reproduction ◽  
2012 ◽  
Vol 144 (5) ◽  
pp. 569-582 ◽  
Author(s):  
Lisa Shaw ◽  
Sharon F Sneddon ◽  
Daniel R Brison ◽  
Susan J Kimber

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.


2013 ◽  
Vol 116 ◽  
pp. 1-8 ◽  
Author(s):  
Andrea Matteucci ◽  
Lucia Gaddini ◽  
Gianfranco Macchia ◽  
Monica Varano ◽  
Tamara C. Petrucci ◽  
...  

2000 ◽  
Vol 20 (11) ◽  
pp. 4169-4180 ◽  
Author(s):  
Alison J. Crowe ◽  
Julie L. Piechan ◽  
Ling Sang ◽  
Michelle C. Barton

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.


Development ◽  
2000 ◽  
Vol 127 (17) ◽  
pp. 3703-3713 ◽  
Author(s):  
M. Bouchard ◽  
P. Pfeffer ◽  
M. Busslinger

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.


Development ◽  
1993 ◽  
Vol 118 (2) ◽  
pp. 463-475 ◽  
Author(s):  
L. Tessarollo ◽  
P. Tsoulfas ◽  
D. Martin-Zanca ◽  
D.J. Gilbert ◽  
N.A. Jenkins ◽  
...  

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.


Development ◽  
1999 ◽  
Vol 126 (6) ◽  
pp. 1295-1304 ◽  
Author(s):  
Z. Kozmik ◽  
N.D. Holland ◽  
A. Kalousova ◽  
J. Paces ◽  
M. Schubert ◽  
...  

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.


2004 ◽  
Vol 121 (7-8) ◽  
pp. 977-983 ◽  
Author(s):  
Alessandro Alunni ◽  
Maryline Blin ◽  
Karine Deschet ◽  
Franck Bourrat ◽  
Philippe Vernier ◽  
...  

1996 ◽  
Vol 2 (1) ◽  
pp. 15-23 ◽  
Author(s):  
Hartmut Lüddens ◽  
Esa R. Korpi

τ-Aminobutyric acid (GABA), the most prevalent inhibitory neurotransmitter in the mammalian brain, exerts its main action through GABAA receptors. They belong to the superfamily of ligand-gated ion channels and respond to GABA by the opening of an intrinsic anion channel. Multiple GABAA receptor subtypes in the brain show differential regional and developmental expression patterns. The receptors have a pentameric structure and are formed from members of at least three different subunit families (α1–6, β1–3, and τ1–3). The regulation of functional properties by GABA and its analogs and by benzodiazepine (BZ) receptor ligands differs dramatically with the type of α variant in the receptor complex. Additional variations of GABAA receptors result from substitution of γ subunits. The role of the β subunits, which are essential for receptor assembly, is less well defined on a functional basis. Besides their involvement in anxiolysis and sedation, GABAA receptors clearly have an impact on motor coordination. However, with the possible exception of the alcohol-and BZ-sensitive alcohol non-tolerant (ANT) rat line, it is not well documented whether a genetic alteration in this receptor system is directly involved in the impairment of animal or human motor activity.


Sign in / Sign up

Export Citation Format

Share Document