Expression of p53 during mouse embryogenesis

Development ◽  
1991 ◽  
Vol 113 (3) ◽  
pp. 857-865 ◽  
Author(s):  
P. Schmid ◽  
A. Lorenz ◽  
H. Hameister ◽  
M. Montenarh

By in situ hybridisation we have examined the expression of p53 during mouse embryogenesis from day 8.5 to day 18.5 post coitum (p.c.). High levels of p53 mRNA were detected in all cells of the day 8.5 p.c. and 10.5 p.c. mouse embryo. However, at later stages of development, expression became more pronounced during differentiation of specific tissues e.g. of the brain, liver, lung, thymus, intestine, salivary gland and kidney. In cells undergoing terminal differentiation, the level of p53 mRNA declined strongly. In the brain, hybridisation signals were also observed in postmitotic but not yet terminally differentiated cells. Therefore, gene expression of p53 does not appear to be linked with cellular proliferation in this organ. A proposed role for p53 in cellular differentiation is discussed.

2001 ◽  
Vol 27 (1) ◽  
pp. 117-122 ◽  
Author(s):  
NJ Pavlos ◽  
J Xu ◽  
JM Papadimitriou ◽  
MH Zheng

Small GTP-binding proteins of the Rab subfamily are key regulators of intracellular vesicle transport. Here we report the isolation of a cDNA clone encoding the complete Rab3c isoform from mouse embryo using a degenerative PCR-based approach. Multiple sequence alignment revealed that the predicted amino acid sequence was identical to the previously identified rat Rab3c isoform and 98% identical to the published bovine Rab3c GTPase from brain. Furthermore by in situ hybridisation, Rab3c mRNA was detectable within various regions of the brain, cartilage and highly enriched within intestinal villi of foetal tissues. Chondrocytes in the hypertrophic zone, but not reserve or proliferative zones, expressed high levels of Rab3c. This pattern of expression corresponds with the genesis of matrix vesicles during endochondral ossification.In all, our results suggest that in addition to its functional role during regulated secretion in brain, Rab3c may play a part in matrix vesicle trafficking during skeletal development.


1990 ◽  
Vol 110 (3) ◽  
pp. 607-616 ◽  
Author(s):  
K Kadomatsu ◽  
R P Huang ◽  
T Suganuma ◽  
F Murata ◽  
T Muramatsu

A newly identified gene MK is transiently expressed in early stages of retinoic acid-induced differentiation of embryonal carcinoma cells (Kadomatsu, K., M. Tomomura, and T. Muramatsu, 1988. Biochem. Biophys. Res. Commun. 151:1312-1318). MK gene has been predicted to code a polypeptide that is rich in basic amino acids and cysteine and is not related to any other peptides so far reported. In the present study, we investigated MK expression during mouse embryogenesis by in situ hybridization. The MK transcript was detected all over the embryo proper of the 7-d embryo, while it was not detectable in the 5-d embryo. The ubiquitous expression continued in the 9-d embryo proper. On the 11th-13th d of gestation, the sites where MK gene was intensely expressed became progressively restricted; these sites were the brain ectoderm around the lens and brain ventricles, the anterior lobe of the pituitary gland, the upper and lower jaw, the caudal sclerotomic half of vertebral column, the limbs, the stomach, and the epithelial tissues of the lung, the pancreas, the small intestine, and the metanephros. These areas include the region where secondary embryonic induction is prominent. In the 15-d embryo, only the kidney expressed MK significantly. These data suggest that MK gene plays a fundamental role in the differentiation of a wide variety of cells; MK gene may also play some specific roles in generation of epithelial tissues, and remodeling of mesoderm.


2005 ◽  
Vol 17 (7) ◽  
pp. 693 ◽  
Author(s):  
Sharon E. Mitchell ◽  
John J. Robinson ◽  
Margaret E. King ◽  
Lynda M. Williams

In sheep, inflammation not only functions in cervical dilation at parturition, but also plays an important part in the non-pregnant ewe cervix, as demonstrated by the high level of expression of interleukin (IL)-8 at oestrus. Ewes artificially induced to ovulate have significantly lower levels of IL-8 gene expression at oestrus compared with natural oestrus, indicating an inhibition of inflammation and function, offering an explanation for the low rates of conception in vaginally inseminated synchronised ewes. To identify potential pro-inflammatory agents to combat the anti-inflammatory effects of hormonal synchronisation of oestrus, we have investigated the role of proteinase-activated receptor (PAR)-1 and PAR-2. To localise and measure the level of expression of these receptors, ovine-specific probes were derived for PAR-1 and PAR-2 and used for quantitative in situ hybridisation in the ovine cervix. Both PAR-1 and PAR-2 were expressed in the luminal epithelium of the cervix throughout the oestrous cycle, with expression being highest at oestrus. The gene expression of PAR-2 at oestrus was approximately 30% higher than that of PAR-1. Artificial synchronisation of oestrus by either an intravaginal progesterone sponge or prostaglandin F2α injections did not inhibit PAR-1 or PAR-2 expression at oestrus; rather, in the case of PAR-2, progesterone synchronisation increased it. Both synchronising procedures increased the expression of PAR-1 and PAR-2 during the luteal phase of the cycle. Therefore, agonists of PAR-1 and PAR-2 may be potentially useful pro-inflammatory agents countering the inhibition of inflammation by hormonal synchronisation.


2000 ◽  
pp. 809-816 ◽  
Author(s):  
U Michel ◽  
S Ebert ◽  
O Schneider ◽  
Y Shintani ◽  
S Bunkowski ◽  
...  

OBJECTIVE: Follistatin (FS) is the specific binding protein of activin and expression of both factors is regulated by inflammatory agents. Therefore, FS concentrations were determined in cerebrospinal fluid (CSF) of patients with bacterial and viral meningitis or multiple sclerosis (MS), as well as in the CSF of patients without meningial inflammation or autoimmune diseases. Furthermore, a mouse pneumococcal meningitis model was used to localise the cellular sources of FS in brains of normal and meningitic mice. METHODS: FS concentrations in CSF were determined by ELISA; FS in mice was localised by in situ hybridisation and immunohistochemistry. RESULTS: FS concentrations were > or =0.4 microg/l in 22 of 66 CSF samples of meningitis patients versus 2 of 27 CSF samples from patients with multiple sclerosis (P<0.05) and 2 of 41 CSF specimen from patients without neuroinflammatory diseases (P<0.01). In the CSF of patients with meningitis, the concentration of FS was correlated with total protein (P<0.005) and lactate concentrations (P<0.05), but not with leukocyte counts, interval between onset of disease and CSF analysis, or clinical outcome. The CSF-to-serum ratios of FS and albumin also correlated significantly (P<0.0005). In some patients with meningitis the CSF-to-serum ratios suggested that the elevated FS in CSF did not originate from serum alone. FS was localised in mice brains to neurones of the hippocampus, dentate gyrus, neocortex, and to the choroid plexus. Analyses of brains and other organs from uninfected and infected animals sacrificed 6-36 h after infection did not reveal any obvious differences in the distribution and intensity of FS mRNA and protein expression. CONCLUSIONS: The concentration of FS in humans is elevated during meningitis. In some patients the increase is caused by a release of FS from brain into CSF. Data from the mouse meningitis model suggest that increased CSF concentrations of FS in meningitis appear not to be accompanied by an elevated number of cells containing FS mRNA or protein in the brain.


2021 ◽  
Author(s):  
Olivia R A Tidswell ◽  
Matthew A Benton ◽  
Michael E Akam

In Drosophila, segmentation genes of the gap class form a regulatory network that positions segment boundaries and assigns segment identities. This gene network shows striking parallels with another gene network known as the neuroblast timer series. The neuroblast timer genes hunchback, Krüppel, nubbin, and castor are expressed in temporal sequence in neural stem cells to regulate the fate of their progeny. These same four genes are expressed in corresponding spatial sequence along the Drosophila blastoderm. The first two, hunchback and Krüppel, are canonical gap genes, but nubbin and castor have limited or no roles in Drosophila segmentation. Whether nubbin and castor regulate segmentation in insects with the ancestral, sequential mode of segmentation remains largely unexplored. We have investigated the expression and functions of nubbin and castor during segment patterning in the sequentially-segmenting beetle Tribolium. Using multiplex fluorescent in situ hybridisation, we show that Tc-hunchback, Tc-Krüppel, Tc-nubbin and Tc-castor are expressed sequentially in the segment addition zone of Tribolium, in the same order as they are expressed in Drosophila neuroblasts. Furthermore, simultaneous disruption of multiple genes reveals that Tc-nubbin regulates segment identity, but does so redundantly with two previously described gap/gap-like genes, Tc-giant and Tc-knirps. Knockdown of two or more of these genes results in the formation of up to seven pairs of ectopic legs on abdominal segments. We show that this homeotic transformation is caused by loss of abdominal Hox gene expression, likely due to expanded Tc-Krüppel expression. Our findings support the theory that the neuroblast timer series was co-opted for use in insect segment patterning, and contribute to our growing understanding of the evolution and function of the gap gene network outside of Drosophila.


2019 ◽  
Author(s):  
Sooyeon Yoo ◽  
David Cha ◽  
Dong Won Kim ◽  
Thanh V. Hoang ◽  
Seth Blackshaw

AbstractLeptin is secreted by adipocytes to regulate appetite and body weight. Recent studies have reported that tanycytes actively transport circulating leptin across the brain barrier into the hypothalamus, and are required for normal levels of hypothalamic leptin signaling. However, direct evidence for leptin receptor (LepR) expression is lacking, and the effect of tanycyte-specific deletion of LepR has not been investigated. In this study, we analyze the expression and function of the tanycytic LepR in mice. Using single-molecule fluorescent in situ hybridization (smfISH), RT-qPCR, single-cell RNA sequencing (scRNA-Seq), and selective deletion of the LepR in tanycytes, we are unable to detect expression of LepR in the tanycytes. Tanycyte-specific deletion of LepR likewise did not affect leptin-induced pSTAT3 expression in hypothalamic neurons, regardless of whether leptin was delivered by intraperitoneal or intracerebroventricular injection. Finally, we use activity-regulated scRNA-Seq (act-Seq) to comprehensively profile leptin-induced changes in gene expression in all cell types in mediobasal hypothalamus. Clear evidence for leptin signaling is only seen in endothelial cells and subsets of neurons, although virtually all cell types show leptin-induced changes in gene expression. We thus conclude that LepR expression in tanycytes is either absent or undetectably low, that tanycytes do not directly regulate hypothalamic leptin signaling through a LepR-dependent mechanism, and that leptin regulates gene expression in diverse hypothalamic cell types through both direct and indirect mechanisms.


2021 ◽  
Vol 22 (22) ◽  
pp. 12228
Author(s):  
Philip Bertemes ◽  
Robert Pjeta ◽  
Julia Wunderer ◽  
Alexandra L. Grosbusch ◽  
Birgit Lengerer ◽  
...  

Many free-living flatworms have evolved a temporary adhesion system, which allows them to quickly attach to and release from diverse substrates. In the marine Macrostomum lignano, the morphology of the adhesive system and the adhesion-related proteins have been characterised. However, little is known about how temporary adhesion is performed in other aquatic environments. Here, we performed a 3D reconstruction of the M. lignano adhesive organ and compared it to the morphology of five selected Macrostomum, representing two marine, one brackish, and two freshwater species. We compared the protein domains of the two adhesive proteins, as well as an anchor cell-specific intermediate filament. We analysed the gene expression of these proteins by in situ hybridisation and performed functional knockdowns with RNA interference. Remarkably, there are almost no differences in terms of morphology, protein regions, and gene expression based on marine, brackish, and freshwater habitats. This implies that glue components produced by macrostomids are conserved among species, and this set of two-component glue functions from low to high salinity. These findings could contribute to the development of novel reversible biomimetic glues that work in all wet environments and could have applications in drug delivery systems, tissue adhesives, or wound dressings.


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