64 X-LINKED GENE EXPRESSION IN BOVINE ( <i>BOS TAURUS</i> ) MALE AND FEMALE <i>IN VITRO</i> - FERTILIZED AND SOMATIC CELL NUCLEAR TRANSFER-DERIVED BLASTOCYSTS
Notice bibliographique
Résumé
Expression of some X-chromosome linked genes has recently been shown to be altered in bovine somatic cell nuclear transfer (SCNT) derived embryos (Wrenzycki et al. 2002 Biol. Reprod. 66, 127), implying that the regulatory mechanisms of X-linked transcription are affected by embryo in vitro production (IVP) methods. We analyzed the transcriptional pattern of X-linked genes ( BIRC4 , GAB3 , HPRT1 , MECP2 , RPS4X , SLC25A6 , and XIST ) in bovine in vitro fertilized (IVF) and SCNT male and female blastocysts to determine X-inactivation status and changes resulting from IVP. We collected pools of male ( n = 5 pools) and female ( n = 3 pools) IVF-derived blastocysts (Bousquet et al. 1999 Theriogenology 51, 59) and male ( n = 5 pools) and female ( n = 3 pools) SCNT-derived blastocysts (Mastromonaco et al. 2004 Reprod. Domest. Anim. 39, 462). Each pool consisted of five blastocysts. Embryos were washed in phosphate buffered saline (PBS) + 0.1% polyvinyl alcohol (PVA), collected, and stored at -80°C. Total RNA was extracted with an Absolutely RNA Microprep kit (Stratagene, La Jolla, CA, USA), DNase I treated, and precipitated with isopropanol and linear acrylamide (Ambion, Inc., Austin, TX, USA) as a carrier. Reverse transcription was performed with Oligo-dT (Invitrogen, Burlington, Ontario, Canada) and Superscript II RT (Invitrogen). Transcript quantification was performed by quantitative real-time PCR using SYBR Green I (LightCycler system, Roche, Diagnostics, Laval, Quebec, Canada). Data analysis was performed with SAS (SAS Institute, Inc., Cary, SC, USA) using a mixed-model factorial ANOVA and with results presented as estimates of the median, ratios of estimates, and 95% confidence intervals with ± = 0.05. IVF-derived male and female blastocysts possessed similar levels of the transcripts analyzed, suggesting successful dosage compensation at this developmental stage for embryos fertilized in vitro . XIST was not detected in male IVF embryos. GAB3 was not detected in any of the female groups and, in addition, HPRT1 transcripts were not detected in SCNT derived female embryos. Male and female SCNT-derived blastocysts possessed marked differences in their transcript levels, with males showing statistically significantly higher levels of BIRC4 and RPS4X and females possessing higher levels of MECP2 and SLC25A6 transcripts although differences between the latter two were not statistically significant. XIST was detected in both male and female SCNT blastocysts. We conclude that dosage compensation between male and female IVF blastocysts is achieved at this developmental stage for the transcripts examined. However, this pattern was markedly changed in the SCNT group, affecting especially female SCNT blastocysts, suggesting that the regulatory mechanisms of X-inactivation and X-linked gene expression are substantially altered in SCNT embryos probably due to aberrant epigenetic patterns and faulty genome reprogramming. We are currently analyzing X-linked transcription in male and female in vivo -derived blastocysts in order to compare this group with IVP-derived embryos. This work was funded by NSERC, CIHR, and CRC.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».