Maternally derived transcripts: identification and characterisation during oocyte maturation and early cleavage

2007 ◽  
Vol 19 (1) ◽  
pp. 25 ◽  
Author(s):  
Xiang-Shun Cui ◽  
Nam-Hyung Kim

The identification and characterisation of differentially regulated genes in oocytes and early embryos are required to understand the mechanisms involved in maturation, fertilisation, early cleavage and even long-term development. Several methods, including reverse transcription–polymerase chain reaction-based suppression subtractive hybridisation, differential display and cDNA microarray, have been applied to identify maternally derived genes in mammalian oocytes. However, conventional gene-knockout experiments to determine specific gene functions are labour intensive and inefficient. Recent developments include the use of RNA interference techniques to establish specific gene functions in mammalian oocytes and early embryos. Regulation of the poly(A) tail length is a major factor in controlling the activities of maternal transcripts in mammals. Further studies are required to clarify the mechanisms by which expression levels of maternally derived transcripts are regulated. In the present review, we focus on the identification and functions of the differentially expressed transcripts during oocyte maturation, fertilisation and early cleavage.

2005 ◽  
Vol 17 (6) ◽  
pp. 625 ◽  
Author(s):  
Xiang-Shun Cui ◽  
Hyuk Song ◽  
Nam-Hyung Kim

Annealing control primer (ACP)-based GeneFishing polymerase chain reaction (PCR) was used to identify the genes that are specifically or prominently expressed in porcine oocytes at the metaphase II (MII) and germinal vesicle (GV) stages. By using 60 ACPs, 13 differentially expressed genes (DEGs) were identified. The cloned genes or expressed sequence tags (ESTs) showed sequence similarity with known genes or ESTs of other species in GenBank. The mRNA expression during oocyte maturation and early embryonic development in both pigs and mice of four of these genes (namely transcription factor TZP, annexin A2, hypoxia-inducible protein 2, and ATPase 6) was further characterised by real-time quantitative reverse transcription–PCR. All four genes were markedly upregulated in pig and mouse MII oocytes compared with GV-stage oocytes. The expression levels of the four genes decreased gradually during early cleavage. Thus, these genes may play important roles during oocyte maturation and/or early cleavage in mammals. Although the detailed functions of these genes remain to be determined, their identification in the present study provides insights into meiotic maturation and fertilisation.


1987 ◽  
Vol 104 (5) ◽  
pp. 1133-1142 ◽  
Author(s):  
M A Nash ◽  
S E Kozak ◽  
L M Angerer ◽  
R C Angerer ◽  
H Schatten ◽  
...  

We have used in situ hybridization and cell fractionation methods to follow the distribution of U1 RNA and immunofluorescence microscopy to follow the distribution of snRNP proteins in oocytes, eggs, and embryos of several sea urchin species. U1 RNA and U1-specific snRNP antigens are concentrated in germinal vesicles of oocytes. Both appear to relocate after oocyte maturation because they are found primarily, if not exclusively, in the cytoplasm of mature unfertilized eggs. This cytoplasmic residence is maintained during early cleavage and U1 RNA is first detectable in nuclei of micromeres at the 16-cell stage. Between morula and gastrula stages the steady-state concentrations of both RNA and antigens gradually increase in nuclei and decrease in cytoplasm. Surprisingly, analysis of the distribution of newly synthesized U1 RNA shows that it does not equilibrate with the maternal pool. Instead new transcripts are confined to nuclei, while cytoplasmic U1 RNAs are of maternal origin. This lack of equilibration and the conversion of maternal U1 RNAs from nuclear species in oocytes to cytoplasmic in embryos suggests that these RNPs (or RNAs) are structurally altered when released to the cytoplasm at oocyte maturation.


eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Stephen W Eichhorn ◽  
Alexander O Subtelny ◽  
Iva Kronja ◽  
Jamie C Kwasnieski ◽  
Terry L Orr-Weaver ◽  
...  

Because maturing oocytes and early embryos lack appreciable transcription, posttranscriptional regulatory processes control their development. To better understand this control, we profiled translational efficiencies and poly(A)-tail lengths throughout Drosophila oocyte maturation and early embryonic development. The correspondence between translational-efficiency changes and tail-length changes indicated that tail-length changes broadly regulate translation until gastrulation, when this coupling disappears. During egg activation, relative changes in poly(A)-tail length, and thus translational efficiency, were largely retained in the absence of cytoplasmic polyadenylation, which indicated that selective poly(A)-tail shortening primarily specifies these changes. Many translational changes depended on PAN GU and Smaug, and these changes were largely attributable to tail-length changes. Our results also revealed the presence of tail-length–independent mechanisms that maintained translation despite tail-length shortening during oocyte maturation, and prevented essentially all translation of bicoid and several other mRNAs before egg activation. In addition to these fundamental insights, our results provide valuable resources for future studies.


Author(s):  
Chanseob Shim ◽  
Sang Gu Lee ◽  
Woo Keun Song ◽  
Chul Sang Lee ◽  
Kyung-Kwang Lee ◽  
...  

2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
Mattia Quattrocelli ◽  
Michelle Wintzinger ◽  
Karen Miz

Glucocorticoid steroids are circadian regulators of energy balance. However, the specific direct effects of glucocorticoids on heart metabolism remain unresolved. Moreover, the impact of circadian time-of-intake on glucocorticoid pharmacology is still unknown. Here, we investigated whether circadian time of exposure gates the effects of synthetic glucocorticoids on heart bioenergetics. We compared the effects of diurnal versus nocturnal glucocorticoids in heart tissue and mitochondria from wildtype mice, controlling the subjective circadian time of drug injection. To avoid interferences from other tissues, we developed an ex vivo system to interrogate the mitochondrial respiratory capacity rate (state III/state IV) in isolated hearts. We found that diurnal but not nocturnal pulse of the glucocorticoid prednisone increased the mitochondrial respiratory capacity rate in heart. This correlated with circadian-restricted effects on mitochondrial abundance. This was remarkable as it contrasts the circadian fluctuations of endogenous glucocorticoids. Using transgenic mice with inducible cardiac-specific gene knockout, we found that the bioenergetic effects of diurnal-restricted prednisone were dependent on the glucocorticoid receptor and its co-factor Kruppel-like factor 15. Considering the bioenergetic decline that hallmarks the aging heart, we asked whether these circadian-gated effects were applicable to aged mice. We therefore treated 24 months-old mice for 12 weeks with a diurnal-restricted regimen of prednisone. Compared to vehicle, diurnal prednisone increased mitochondrial respiration along with NAD + and ATP content in aged hearts. Moreover, lipidomic profiling of myocardial tissue showed that the vast majority of lipids were downregulated after treatment, including triacylglycerols, suggesting a functional coupling between lipid utilization and mitochondrial oxidation in treated hearts. We also found that diurnal-restricted prednisone rescued bioenergetics and improved function in diabetic hearts from db/db mice. In summary, our data indicate that glucocorticoids regulate cardiac bioenergetics according to circadian-time of intake, supporting a role for chrono-pharmacology in aged and diabetic hearts.


2004 ◽  
Vol 5 (3) ◽  
pp. 219-226 ◽  
Author(s):  
Satoko Arai ◽  
Christina Minjares ◽  
Seiho Nagafuchi ◽  
Toru Miyazaki

The manipulation of a specific gene in NOD mice, the best animal model for insulin-dependent diabetes mellitus (IDDM), must allow for the precise characterization of the functional involvement of its encoded molecule in the pathogenesis of the disease. Although this has been attempted by the cross-breeding of NOD mice with many gene knockout mice originally created on the 129 or C57BL/6 strain background, the interpretation of the resulting phenotype(s) has often been confusing due to the possibility of a known or unknown disease susceptibility locus (e.g.,Iddlocus) cosegregating with the targeted gene from the diabetes-resistant strain. Therefore, it is important to generate mutant mice on a pure NOD background by using NOD-derived embryonic stem (ES) cells. By using the NOD ES cell line established by Nagafuchi and colleagues in 1999 (FEBSLett., 455, 101–104), the authors reexamined various conditions in the context of cell culture, DNA transfection, and blastocyst injection, and achieved a markedly improved transmission efficiency of these NOD ES cells into the mouse germ line. These modifications will enable gene targeting on a “pure” NOD background with high efficiency, and contribute to clarifying the physiological roles of a variety of genes in the disease course of IDDM.


Genome ◽  
2006 ◽  
Vol 49 (7) ◽  
pp. 808-814
Author(s):  
T H.L Smith ◽  
K Stedronsky ◽  
B Morgan ◽  
R A McGowan

In this report, we describe the cloning of a cDNA from the zebrafish Danio rerio encoding a protein containing a BTB–POZ domain closely resembling the BTBD1 and BTBD2 proteins previously identified in mammals. However, unlike other BTB–POZ-containing genes, expression of this gene in adults is most abundant in oocytes, where the RNA can be detected at all stages of oogenesis examined. The presence of the RNA persists through early cleavage, but is decreased significantly by gastrulation. Although the function of this gene has yet to be determined, its resemblance to the BTB–POZ family of genes coupled with its expression pattern suggests that it may have an important function in oogenesis and (or) early zebrafish development.Key words: BTBD1, BTBD2, BTB–POZ domain, kelch superfamily, PHR domain.


2007 ◽  
Vol 13 ◽  
pp. 501-504
Author(s):  
R. Johnson ◽  
A. Khan ◽  
C. Voisey ◽  
S. Bassett ◽  
C. Gaborit ◽  
...  

As a first step towards a functional genomics approach to gain a greater understanding of this important symbiosis, we have generated, sequenced and analysed two EST libraries from cultures of N. lolii and six in planta subtracted EST libraries enriched for differentially expressed genes. A total of 12871 ESTs were sequenced which, after filtering for quality, clustered into 1066 contigs and 3230 singletons to give a set of 4296 unique sequences or unigenes. BLASTX analysis revealed that 60% of fungal sequences derived from cultures were of unknown function with a sub-set of these corresponding to orphans. For the in planta-derived ESTs, most of the sequences with homologs in the public databases (98%) were of ryegrass origin. Comparisons made against fully sequenced genomes revealed that most fungal ESTs were homologous to genes present in both pathogenic and non-pathogenic ascomycete filamentous fungi, whereas the subtracted libraries comprised mostly plant genes. A range of sequences having significant homology to demonstrated pathogenicity/virulence genes in other fungal pathosystems were also identified, as well as some ESTs with proven roles in endophyte secondary metabolism. Keywords: ESTs, cDNA, Neotyphodium lolii, Lolium perenne, symbiosis, mutualism, suppression subtractive hybridisation


Sign in / Sign up

Export Citation Format

Share Document