Limits...
Maternal LSD1/KDM1A is an essential regulator of chromatin and transcription landscapes during zygotic genome activation.

Ancelin K, Syx L, Borensztein M, Ranisavljevic N, Vassilev I, Briseño-Roa L, Liu T, Metzger E, Servant N, Barillot E, Chen CJ, Schüle R, Heard E - Elife (2016)

Bottom Line: Upon fertilization, the highly specialised sperm and oocyte genomes are remodelled to confer totipotency.The mechanisms of the dramatic reprogramming events that occur have remained unknown, and presumed roles of histone modifying enzymes are just starting to be elucidated.At the transcriptional level, the switch of the maternal-to-zygotic transition fails to be induced properly and LINE-1 retrotransposons are not properly silenced.

View Article: PubMed Central - PubMed

Affiliation: Institut Curie, Paris, France.

ABSTRACT
Upon fertilization, the highly specialised sperm and oocyte genomes are remodelled to confer totipotency. The mechanisms of the dramatic reprogramming events that occur have remained unknown, and presumed roles of histone modifying enzymes are just starting to be elucidated. Here, we explore the function of the oocyte-inherited pool of a histone H3K4 and K9 demethylase, LSD1/KDM1A during early mouse development. KDM1A deficiency results in developmental arrest by the two-cell stage, accompanied by dramatic and stepwise alterations in H3K9 and H3K4 methylation patterns. At the transcriptional level, the switch of the maternal-to-zygotic transition fails to be induced properly and LINE-1 retrotransposons are not properly silenced. We propose that KDM1A plays critical roles in establishing the correct epigenetic landscape of the zygote upon fertilization, in preserving genome integrity and in initiating new patterns of genome expression that drive early mouse development.

No MeSH data available.


Related in: MedlinePlus

Immunofluorescence analysis of histone tail modifications upon maternal depletion or upon chemical inhibition of KDM1A for two-cell stage embryos.(A and B) Analysis of heterochromatin marks by IF with antibodies against me3 of H3K27 (A) and H4K20 (B) were performed on f/wt control embryos (left panel) in parallel to Δm/wt mutant embryos (right panel). (C and D) Analysis by IF with antibodies against H3K4me3 (C) and H3K9me3 (D) of two-cell stage wild-type embryos cultured in mock conditions (left panel) or with pargyline (right panel). Antibody staining is shown in green or red and DNA is counterstained with DAPI (blue). The number of embryos processed is indicated under each picture. Shown are full projections of stack sections taken every 0.5 μm. Scale bar, 10 μ. Under each image is the graphical representation of the fluorescent mean intensity ± sem (arbitrary unit, AU) of Δm/wt (in black) relative to f/wt (in white) two-cell stage immunostained embryos.DOI:http://dx.doi.org/10.7554/eLife.08851.008
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4829419&req=5

fig3s1: Immunofluorescence analysis of histone tail modifications upon maternal depletion or upon chemical inhibition of KDM1A for two-cell stage embryos.(A and B) Analysis of heterochromatin marks by IF with antibodies against me3 of H3K27 (A) and H4K20 (B) were performed on f/wt control embryos (left panel) in parallel to Δm/wt mutant embryos (right panel). (C and D) Analysis by IF with antibodies against H3K4me3 (C) and H3K9me3 (D) of two-cell stage wild-type embryos cultured in mock conditions (left panel) or with pargyline (right panel). Antibody staining is shown in green or red and DNA is counterstained with DAPI (blue). The number of embryos processed is indicated under each picture. Shown are full projections of stack sections taken every 0.5 μm. Scale bar, 10 μ. Under each image is the graphical representation of the fluorescent mean intensity ± sem (arbitrary unit, AU) of Δm/wt (in black) relative to f/wt (in white) two-cell stage immunostained embryos.DOI:http://dx.doi.org/10.7554/eLife.08851.008

Mentions: To address the specificity of these effects of KDM1A on H3K4 and H3K9 methylation, we tested other histone marks, reported not to be targeted by KDM1A activity. Two such marks, H3K27me3 and H4K20me3, both associated with heterochromatin, were analysed by IF in f/wt and △m/wt two-cell stage embryos. No significant changes in either of these marks could be detected in mutant compared to control embryos (Figure 3—figure supplement 1A and B), underlining the specificity of the defects found in KDM1A maternally depleted embryos. As an additional control, we performed IF analysis of two-cell stage embryos generated from wild-type zygotes grown for 24 hr with pargyline. H3K4me3 and H3K9me3 patterns revealed changes in pargyline-treated when compared to mock-treated embryos (Figure 3—figure supplement 1C and D). In both, a global increase in staining was detected when compared to controls, although to a slightly lesser extent than in Kdm1a mutant embryos.


Maternal LSD1/KDM1A is an essential regulator of chromatin and transcription landscapes during zygotic genome activation.

Ancelin K, Syx L, Borensztein M, Ranisavljevic N, Vassilev I, Briseño-Roa L, Liu T, Metzger E, Servant N, Barillot E, Chen CJ, Schüle R, Heard E - Elife (2016)

Immunofluorescence analysis of histone tail modifications upon maternal depletion or upon chemical inhibition of KDM1A for two-cell stage embryos.(A and B) Analysis of heterochromatin marks by IF with antibodies against me3 of H3K27 (A) and H4K20 (B) were performed on f/wt control embryos (left panel) in parallel to Δm/wt mutant embryos (right panel). (C and D) Analysis by IF with antibodies against H3K4me3 (C) and H3K9me3 (D) of two-cell stage wild-type embryos cultured in mock conditions (left panel) or with pargyline (right panel). Antibody staining is shown in green or red and DNA is counterstained with DAPI (blue). The number of embryos processed is indicated under each picture. Shown are full projections of stack sections taken every 0.5 μm. Scale bar, 10 μ. Under each image is the graphical representation of the fluorescent mean intensity ± sem (arbitrary unit, AU) of Δm/wt (in black) relative to f/wt (in white) two-cell stage immunostained embryos.DOI:http://dx.doi.org/10.7554/eLife.08851.008
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4829419&req=5

fig3s1: Immunofluorescence analysis of histone tail modifications upon maternal depletion or upon chemical inhibition of KDM1A for two-cell stage embryos.(A and B) Analysis of heterochromatin marks by IF with antibodies against me3 of H3K27 (A) and H4K20 (B) were performed on f/wt control embryos (left panel) in parallel to Δm/wt mutant embryos (right panel). (C and D) Analysis by IF with antibodies against H3K4me3 (C) and H3K9me3 (D) of two-cell stage wild-type embryos cultured in mock conditions (left panel) or with pargyline (right panel). Antibody staining is shown in green or red and DNA is counterstained with DAPI (blue). The number of embryos processed is indicated under each picture. Shown are full projections of stack sections taken every 0.5 μm. Scale bar, 10 μ. Under each image is the graphical representation of the fluorescent mean intensity ± sem (arbitrary unit, AU) of Δm/wt (in black) relative to f/wt (in white) two-cell stage immunostained embryos.DOI:http://dx.doi.org/10.7554/eLife.08851.008
Mentions: To address the specificity of these effects of KDM1A on H3K4 and H3K9 methylation, we tested other histone marks, reported not to be targeted by KDM1A activity. Two such marks, H3K27me3 and H4K20me3, both associated with heterochromatin, were analysed by IF in f/wt and △m/wt two-cell stage embryos. No significant changes in either of these marks could be detected in mutant compared to control embryos (Figure 3—figure supplement 1A and B), underlining the specificity of the defects found in KDM1A maternally depleted embryos. As an additional control, we performed IF analysis of two-cell stage embryos generated from wild-type zygotes grown for 24 hr with pargyline. H3K4me3 and H3K9me3 patterns revealed changes in pargyline-treated when compared to mock-treated embryos (Figure 3—figure supplement 1C and D). In both, a global increase in staining was detected when compared to controls, although to a slightly lesser extent than in Kdm1a mutant embryos.

Bottom Line: Upon fertilization, the highly specialised sperm and oocyte genomes are remodelled to confer totipotency.The mechanisms of the dramatic reprogramming events that occur have remained unknown, and presumed roles of histone modifying enzymes are just starting to be elucidated.At the transcriptional level, the switch of the maternal-to-zygotic transition fails to be induced properly and LINE-1 retrotransposons are not properly silenced.

View Article: PubMed Central - PubMed

Affiliation: Institut Curie, Paris, France.

ABSTRACT
Upon fertilization, the highly specialised sperm and oocyte genomes are remodelled to confer totipotency. The mechanisms of the dramatic reprogramming events that occur have remained unknown, and presumed roles of histone modifying enzymes are just starting to be elucidated. Here, we explore the function of the oocyte-inherited pool of a histone H3K4 and K9 demethylase, LSD1/KDM1A during early mouse development. KDM1A deficiency results in developmental arrest by the two-cell stage, accompanied by dramatic and stepwise alterations in H3K9 and H3K4 methylation patterns. At the transcriptional level, the switch of the maternal-to-zygotic transition fails to be induced properly and LINE-1 retrotransposons are not properly silenced. We propose that KDM1A plays critical roles in establishing the correct epigenetic landscape of the zygote upon fertilization, in preserving genome integrity and in initiating new patterns of genome expression that drive early mouse development.

No MeSH data available.


Related in: MedlinePlus