BRC Strain Name

Strain Name (Nomenclature) Allele Synonyms

1loxGFPXist 1loxGFP mice

Tsix splicing-deficient mice

Xist/Tsix double KO mouse

B6.Cg-Tsix/Xist tm3Sado

B6.Cg-Xist tm4Sado

B6.Cg-Xist tm5Sado

B6.Cg-Xist

tm2SadoB6.Cg-Tsix tm1Sado

B6.Cg-Xist tm1Sado Tsix tm1Enl

B6.Cg-Tsix/Xist tm3Sado

B6.Cg-Xist tm4Sado

B6.Cg-Xist

tm5Sado

Xist
1lox
Xist, Xist

GFP,

Tsix deltaSA

Xist 1lox Tsix AA2delta1.7

Tsix pA

Xist IVS19 , Xist IVS

XistdeltaAAllele type

Description

Developer

Targeted (Reporter)

Xist (X-inactive specific transcript) gene wasdisrupted by replacing part of exon 1 with an
IRES-EGFP cassette. Heterozygous mutant
Sado, T., Hoki, Y., and Sasaki,
females with the mutated allele of paternal origin
Developed by Dr. Sado, H. 2005. Tsix silences Xist
were embryonically lethal by non-random andthrough modification ofNational Institute ofabnormal X-inactivation. The Xist targeting waschromatin structure. Dev Cell 9:
Genetics (2004).
conducted by using normal R1 ES cells. This
159-165.
strain were generated by backcrossing ofheterozygous females with maternal mutant allele
to C57BL/6J male.

Targeted (knock-out)

The function of the Tsix gene, an antisense of theXist gene which is essential for X-inactivation,
Sado, T., Hoki, Y., and Sasaki,
was disrupted by targeting the splicing acceptor
site for exon 4 of Tsix . Female embryos carrying Developed by Dr. Sado, H. 2006. Tsix defective insplicing is competent tomutated TsixdeltaSA allele derived from the father National Institute ofestablish Xist silencing.
Genetics (2006).
are embryonically lethal. The mutated Tsix deltaSA
Development 133: 4925-4931.
allele can be transmitted through heterozygous+deltaSAgenotype.
females of Tsix / Tsix

Targeted (Reporter)

tm1SadoandThe double knockout mice carrying Xist
tm1Enlalleles. The Xist gene was disrupted byTsix
replacing exon 1 with an IRES-EGFP cassette sothat the EGFP reporter is expressed under theSado, T., Hoki, Y., and Sasaki,
control of endogenous promoter. The targeting
was conducted by using mutated J1 ES cells with Developed by Dr. Sado, H. 2005. Tsix silences Xist
through modification ofNational Institute ofdeficient Tsix tm1Enl allele. Female embryos
chromatin structure. Dev Cell 9:
Genetics (2005).
tm1Sadoallele derived fromcarrying mutated Xist
159-165.
the father are embryonically lethal. The mutated
Xist tm1Sado allele can be transmitted through+tm1Sado
heterozygous females of Xist /Xist
genotype.

Targeted (knock-out)

A multiple polyadenylation sequence flanked bysplice donor and acceptor sites was inserted into
exon 4 of Tsix in its orientation. The insertion siteis also within exon 1 of Xist on the other strand.
This genetic modification disrupts the Tsix
Developed by Drs.
transcript affecting the promoter region of the Xist Ohhata and Sado,gene. The absence of transcript expression from National Institute ofXist and Tsix was confirmed by RT-PCR. The
Genetics (2006).
mutated Tsix/Xist tm3Sado allele can be transmitted
tm3Sadothrough heterozygous females of Tsix/Xist
genotype. Germ line, cre-mediated recombination
was used to remove the neo cassette.

Ohhata, T., Hoki, Y., Sasaki, H.,
and Sado, T. 2008. Crucial roleof antisense transcription acrossthe Xist promoter in Tsix mediated Xist chromatinmodification. Development 135:
227-235.

Targeted (knock-out)

The second intron of human gamma globin gene(IVS) with puromycine resistance gene wasinserted into exon 4 of Tsix in its orientation. The
insertion site corresponds to exon 1 of Xist on theother strand. This additional intron disrupts thefunction of the Xist gene, but dose not interferewith elongation of the Tsix transcript across thepromoter region of the Xist gene. This strain isused as control for the Tsix pA . Germ line, cremediated recombination was used to remove theneo cassette.

Ohhata, T., Hoki, Y., Sasaki, H.,
and Sado, T. 2008. Crucial roleof antisense transcription acrossthe Xist promoter in Tsix mediated Xist chromatin
modification. Development 135:
227-235.

Targeted (knock-out)

Hoki, Y., Kimura, N.,
A proximal conserved A-repeat in the Xist gene
Kanbayashi, M., Amakawa, Y.,
was deleted by targeting to elucidate its function
Ohhata, T., Sasaki, H., andfor X-inactivation in mice. The portion of exon 1 Developed by Dr. Sado, Sado, T. 2009. A proximal
encoding the A-repeat was replaced with HSV-tk National Institute ofconserved repeat in the Xistand PGK-neo cassette. Females heterozygous for Genetics (2007).
gene is essential as a genomic
delatA2lox
element for X-inactivation inXist
were crossed with CAG-cre transgenic
delataA
mouse. Development 136: 139males to derive mice carrying Xist.
146.

Developed by Drs.
Ohhata and Sado,
National Institute ofGenetics (2006).

Reference