Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
RNA Biol
2017 Mar 04;143:339-346. doi: 10.1080/15476286.2016.1276695.
Show Gene links
Show Anatomy links
Global decay of mRNA is a hallmark of apoptosis in aging Xenopus eggs.
Tokmakov AA
,
Iguchi S
,
Iwasaki T
,
Fukami Y
,
Sato KI
.
???displayArticle.abstract???
Cytoplasmic mRNAs are specifically degraded in somatic cells as a part of early apoptotic response. However, no reports have been presented so far concerning mRNA fate in apoptotic gametes. In the present study, we analyzed the content of various cytoplasmic mRNAs in aging oocytes and eggs of the African clawed frog, Xenopus laevis. To circumvent large gene expression variation among the individual oocytes and eggs, single-cell monitoring of transcript levels has been implemented, using multiple cytoplasmic collections and reverse transcriptase quantitative PCR. It was found that numerous cytoplasmic mRNAs, coding for proteins classified in different functional types, are robustly degraded in apoptotic Xenopus eggs, but not in aging oocytes. mRNA degradation becomes evident in the eggs after meiotic exit at the time of cytochrome c release. A strong correlation between the length of PCR amplicon and specific transcript content was observed, suggesting endonucleolytic cleavage of mRNA. In addition, it was found that mRNA deadenylation also contributes to apoptotic mRNA degradation. Altogether, these findings indicate that the global decay of mRNA represents a hallmark of apoptosis in aging Xenopus eggs. To our knowledge, this is the first description of mRNA degradation in apoptotic gamete cells.
Figure 1. Variability of transcript contents in Xenopus oocytes. (A) Expression levels of 18 genes measured in a single Xenopus oocyte. (B) Standard deviation of gene expression in the oocyte population determined by analyzing expression levels in 16 to 22 individual oocytes. (C) Sampling design of gene expression monitoring in single aging Xenopus oocytes and eggs. Cytoplasmic collections were made from individual oocytes (O1, O2, O3, O4) before PG treatment, then from the eggs derived from these oocytes at 12, 24, 36 and 48Â hours after PG addition (E1â12, E2â24, E3â36, E4â48, respectively). Cytoplasmic samples were also taken from a control untreated oocyte at the corresponding times (Oc-0, Oc-12, Oc-24, Oc-36, Oc-48). In panel (A), mRNA levels were measured in 2 to 4 replicates. SDs of replicate measurements are small and not visible in the plot.
Figure 2. Changes of specific transcript contents in the oocytes after PG administration. In panels (A), (B), (C), specific transcript levels measured in a single Xenopus oocyte at 12, 24 and 36Â hours after PG administration were referred to those measured in the same oocyte before PG treatment. Difference between the cycle threshold values of the 2 qPCR measurements (ÎCq) was plotted on the y-axis. (D) Changes of specific transcript levels were evaluated in a control oocyte after 48-hour incubation in the absence of PG. In panels (B) and (C) random hexamer (red bars) or oligo(dT) (blue bars) primers were used to generate first strand cDNA by reverse transcription. Transcript levels were measured in 2 to 4 replicates. SDs of replicate measurements are small and not visible in the panels.
Figure 3. Correlations of ÎCq with amplicon length and position obtained with random hexamer RT primers. The results of pairwise correlation analysis between the decrease in transcript level and amplicon distance from the 5â² end, (A) and (D), amplicon distance from the 3â² end, (B) and (E), and amplicon length, (C) and (F), are presented. The decrease in transcript contents was determined for 11 transcripts at 24 hours after PG administration in panels (A), (B), (C) and for 6 transcripts at 36 hours in panels (D), (E), (F), as described in the legend to Fig. 2. First strand cDNA was generated using random hexamer primers. Calculated values of the pairwise correlation coefficient (r) and one-tailed probability test (p) are indicated in the panels.
Figure 4. Correlation between Cq and amplicon length in mcl1 gene transcript observed in apoptotic eggs. Positions and sequences of 5â² qPCR primers targeting qPCR amplicons of different length in mcl1 gene transcript are presented in panels (A) and (B), respectively. First strand cDNA was generated with random hexamer primers. The results of pairwise correlation analysis between Cq and amplicon length are shown in panel (C). Calculated values of the pairwise correlation coefficient (r) and one-tailed probability test (p) are indicated in panel (C).
Figure 5. Correlations of ÎCq with amplicon length and position obtained using oligo(dT) RT primers. Panel (A) presents values of the pairwise correlation coefficient (big fonts) and one-tailed probability test (small fonts) determined at 24 and 36Â hours after PG administration in the experiments using the oligo(dT) RT primer. Panel (B) specifies the region of detectable endonucleolytic degradation in the used experimental design. The results of pairwise correlation analysis between ÎCq and combined length of amplicon plus its distance from the 3â² mRNA end determined for 11 transcripts at 24Â hours and for 6 transcripts at 36Â hours after PG administration are presented in panels (C) and (D), respectively. Calculated values of the pairwise correlation coefficient (r) and one-tailed probability test (p) are indicated in the panels.
Atabasides,
Dephosphorylation, proteolysis, and reduced activity of poly(A) polymerase associated with U937 cell apoptosis.
1998, Pubmed
Atabasides,
Dephosphorylation, proteolysis, and reduced activity of poly(A) polymerase associated with U937 cell apoptosis.
1998,
Pubmed
Brisco,
Quantification of RNA integrity and its use for measurement of transcript number.
2012,
Pubmed
Bushell,
Cleavage of polypeptide chain initiation factor eIF4GI during apoptosis in lymphoma cells: characterisation of an internal fragment generated by caspase-3-mediated cleavage.
2000,
Pubmed
Bushell,
Translation inhibition during the induction of apoptosis: RNA or protein degradation?
2004,
Pubmed
Bushell,
Caspase-3 is necessary and sufficient for cleavage of protein synthesis eukaryotic initiation factor 4G during apoptosis.
1999,
Pubmed
Clemens,
Translation initiation factor modifications and the regulation of protein synthesis in apoptotic cells.
2000,
Pubmed
Crawford,
16S mitochondrial ribosomal RNA degradation is associated with apoptosis.
1997,
Pubmed
Del Prete,
Degradation of cellular mRNA is a general early apoptosis-induced event.
2002,
Pubmed
Du Pasquier,
Unfertilized Xenopus eggs die by Bad-dependent apoptosis under the control of Cdk1 and JNK.
2011,
Pubmed
,
Xenbase
Garneau,
The highways and byways of mRNA decay.
2007,
Pubmed
Ghosh,
RNA decay modulates gene expression and controls its fidelity.
2010,
Pubmed
Graindorge,
Identification of post-transcriptionally regulated Xenopus tropicalis maternal mRNAs by microarray.
2006,
Pubmed
,
Xenbase
Hoat,
Specific cleavage of ribosomal RNA and mRNA during victorin-induced apoptotic cell death in oat.
2006,
Pubmed
Houge,
Fine mapping of 28S rRNA sites specifically cleaved in cells undergoing apoptosis.
1995,
Pubmed
Houge,
Selective cleavage of 28S rRNA variable regions V3 and V13 in myeloid leukemia cell apoptosis.
1993,
Pubmed
Iguchi,
Unlaid Xenopus eggs degrade by apoptosis in the genital tract.
2013,
Pubmed
,
Xenbase
Kalinowska,
Regulation of the human apoptotic DNase/RNase endonuclease G: involvement of Hsp70 and ATP.
2005,
Pubmed
King,
28S ribosome degradation in lymphoid cell apoptosis: evidence for caspase and Bcl-2-dependent and -independent pathways.
2000,
Pubmed
Kosubek,
Aging of Xenopus tropicalis eggs leads to deadenylation of a specific set of maternal mRNAs and loss of developmental potential.
2010,
Pubmed
,
Xenbase
Lafarga,
Apoptosis induced by methylazoxymethanol in developing rat cerebellum: organization of the cell nucleus and its relationship to DNA and rRNA degradation.
1997,
Pubmed
Larsen,
The caspase-activated DNase: apoptosis and beyond.
2017,
Pubmed
Marissen,
Degradation of poly(A)-binding protein in apoptotic cells and linkage to translation regulation.
2004,
Pubmed
Marissen,
Eukaryotic translation initiation factor 4G is targeted for proteolytic cleavage by caspase 3 during inhibition of translation in apoptotic cells.
1998,
Pubmed
Martin,
Induction of apoptosis (programmed cell death) in human leukemic HL-60 cells by inhibition of RNA or protein synthesis.
1990,
Pubmed
Mroczek,
Apoptotic signals induce specific degradation of ribosomal RNA in yeast.
2008,
Pubmed
Rozen,
Primer3 on the WWW for general users and for biologist programmers.
2000,
Pubmed
Sasaki,
Fertilization blocks apoptosis of starfish eggs by inactivation of the MAP kinase pathway.
2001,
Pubmed
Slomovic,
Detection and characterization of polyadenylated RNA in Eukarya, Bacteria, Archaea, and organelles.
2008,
Pubmed
Subtelny,
Poly(A)-tail profiling reveals an embryonic switch in translational control.
2014,
Pubmed
,
Xenbase
Thomas,
Apoptosis Triggers Specific, Rapid, and Global mRNA Decay with 3' Uridylated Intermediates Degraded by DIS3L2.
2015,
Pubmed
Tokmakov,
Unfertilized frog eggs die by apoptosis following meiotic exit.
2011,
Pubmed
,
Xenbase
Tokmakov,
Monitoring gene expression in a single Xenopus oocyte using multiple cytoplasmic collections and quantitative RT-PCR.
2014,
Pubmed
,
Xenbase
Voronina,
Apoptosis in sea urchin oocytes, eggs, and early embryos.
2001,
Pubmed
Widlak,
Discovery, regulation, and action of the major apoptotic nucleases DFF40/CAD and endonuclease G.
2005,
Pubmed
Yuce,
Postmeiotic unfertilized starfish eggs die by apoptosis.
2001,
Pubmed
Zhou,
Interferon action and apoptosis are defective in mice devoid of 2',5'-oligoadenylate-dependent RNase L.
1997,
Pubmed