PMID- 11891913
OWN - NLM
STAT- MEDLINE
DCOM- 20020702
LR  - 20131121
IS  - 1040-452X (Print)
IS  - 1040-452X (Linking)
VI  - 61
IP  - 4
DP  - 2002 Apr
TI  - Developmentally-regulated changes of Xist RNA levels in single preimplantation 
      mouse embryos, as revealed by quantitative real-time PCR.
PG  - 425-36
AB  - Xist RNA localizes to the inactive X chromosome in cells of late cleavage stage 
      female mouse embryos (Sheardown et al., 1997: Cell 91:99-107). Fluorescence in 
      situ hybridization (FISH), however, does not quantify the number of Xist 
      transcripts per nucleus. We have used real-time reverse transcription-polymerase 
      chain reaction (RT-PCR) to measure Xist RNA levels in single preimplantation 
      embryos and to establish developmental profiles in both female and male samples. 
      The gender of each embryo was readily established based on Xist RNA levels, by 
      counting Xist gene copies per cell, and by independent detection of the 
      presence/absence of Sry, a Y chromosome-specific gene. Xist expression in males 
      was found to be very low at all stages, as suggested by FISH. In contrast, female 
      embryos contained measurable levels of Xist mRNA starting at the late 2-cell 
      stage and rapidly accumulated Xist transcripts until morula stage. Xist RNA 
      accumulation per embryo then reached a plateau, while cell division continued. We 
      propose that during early cleavage high enough levels of Xist mRNA are 
      transcribed to generate a pool of unbound molecules. This pool would serve to 
      temporarily maintain X chromosome inactivation without additional transcription 
      while the trophectoderm and inner cell mass (ICM) differentiate. The ICM would 
      then loose the paternally imprinted pattern of X inactivation originally present 
      in all embryonic cells.
FAU - Hartshorn, Cristina
AU  - Hartshorn C
AD  - Department of Biology, Brandeis University, Waltham, Massachusetts 02454-9110, 
      USA. hartcris@brandeis.edu
FAU - Rice, John E
AU  - Rice JE
FAU - Wangh, Lawrence J
AU  - Wangh LJ
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Mol Reprod Dev
JT  - Molecular reproduction and development
JID - 8903333
RN  - 0 (DNA-Binding Proteins)
RN  - 0 (Nuclear Proteins)
RN  - 0 (RNA, Long Noncoding)
RN  - 0 (RNA, Untranslated)
RN  - 0 (Sex-Determining Region Y Protein)
RN  - 0 (Sry protein, mouse)
RN  - 0 (Transcription Factors)
RN  - 0 (XIST non-coding RNA)
RN  - 63231-63-0 (RNA)
SB  - IM
MH  - Animals
MH  - Blastocyst/*physiology
MH  - DNA-Binding Proteins/physiology
MH  - Dosage Compensation, Genetic
MH  - Female
MH  - Gene Expression Regulation, Developmental/*physiology
MH  - Male
MH  - Mice
MH  - *Nuclear Proteins
MH  - Polymerase Chain Reaction
MH  - Pregnancy
MH  - RNA/*physiology
MH  - RNA, Long Noncoding
MH  - RNA, Untranslated/*physiology
MH  - Sex Determination Analysis/methods
MH  - Sex-Determining Region Y Protein
MH  - Transcription Factors/*physiology
EDAT- 2002/03/14 10:00
MHDA- 2002/07/03 10:01
CRDT- 2002/03/14 10:00
PHST- 2002/03/14 10:00 [pubmed]
PHST- 2002/07/03 10:01 [medline]
PHST- 2002/03/14 10:00 [entrez]
AID - 10.1002/mrd.10037 [pii]
AID - 10.1002/mrd.10037 [doi]
PST - ppublish
SO  - Mol Reprod Dev. 2002 Apr;61(4):425-36. doi: 10.1002/mrd.10037.