Table 1

Characteristics of chromatin modifiers and mutant ES cells

Name
Protein function
ES cell lines
Phenotype of KO/DKO mice
Phenotype of KO/DKO ES cells
Reference

Mll
HMTase: tri-methylation of H3K4
KO: High 6
Embryonic lethal (E11.5-14.5)
Homeotic transformations
Mis-regulation of Hox gene expression
Mis-regultion of Hox genes
Failure of in vitro differentiation to hematopoietic pre-cursors
[42-44]
Eed
Subunit of PRC2 Cofactor for Ezh2 (H3K27 HMTase)
KO: B1.3, G8.1
Embryonic lethal (E6.5)
Failure to maintain inactive X in trophoblast derivatives
Loss of H3K27me2/3
Reduced H3K27me1
Contribute to all tissues of chimeras
[4,45-47]
Dnmt1
Maintenance DNA methyl transferase
KO: c/c
Embryonic lethal (E11.5)
Reduced DNA methylation level
Reduced differentiation
[36,48,49]
Dnmt 3a/3b
De novo DNA methyl transferase
DKO: clone 10 (early passage)
Embryonic lethal (E11.5)
Lack de novo DNA methylation activity DNA methylation levels slightly reduced in early passage (severly reduced in late passage cells)
Retains differentiation potential at early passages
[27,37,50]
Mbd3
Subunit of NuRD (nucleosome remodeling and HDAC complex)
KO: Fix2
Embryonic lethal (implantation)
Loss of the NuRD (nucleosome remodeling and HDAC) complex
Severe differentiation block
[38,51]
G9a
HMTase: H3K9me H3K9me2 euchromatic
WT: Col4
KO: 2-3
Tg: 15-3
Embryonic lethal (E12.5)
Reduced H3K9me2
Increased H3K4me2, H3K9ac
Reduced H3K9 methylation in euchromatin
[18,25]
Suv39 h1/h2
H3K9me3 (hetero-chromatic)
WT: wt26
DKO: DN57, DN72
Increased prenatal lethality
Growth retarded
B-cell lymphomas
Male sterility
Chromosome instablility in fibroblasts
Reduced H3K9me3 level; Reduced H3K9me3 at pericentric heterochromatin
Increased H3K27me3 at pericentric heterochromatin
Decreased CpG methylation of satellite repeats
Increased transcription of major/minor satellite
[25,35,52,53]
Dicer
RNase, essential for siRNA/miRNA pathway in mammals
WT: D3
KO: D3-S5, D3-S6
Embryonic lethal (E7.5)
Increased transcription of repeats Slow growth
[30,54,55]

miRNA, microRNA.

Jørgensen et al. Genome Biology 2007 8:R169   doi:10.1186/gb-2007-8-8-r169