Bernardi M L, Cotinot C, Payen E, Delouis C
Génétique Moléculaire et Cellulaire, INRA-ENVA, Maisons-Alfort, France.
Mol Reprod Dev. 1996 Oct;45(2):132-8. doi: 10.1002/(SICI)1098-2795(199610)45:2<132::AID-MRD4>3.0.CO;2-U.
Because male ovine embryos develop faster than female embryos, the transcription of SRY and ZFY, two genes located on the Y chromosome, was examined in preimplantation stages using the reverse transcriptase polymerase chain reaction (RT-PCR). RNA was extracted from pools of ovine embryos matured and fertilized in vitro then cultured in synthetic oviduct fluid medium and recovered from 24 to 207 hr post-insemination (two-cell up to hatched blastocyst stage). Since primers used to amplify ZFY also amplify the homologue ZFX, located on the X chromosome, transcripts were differentiated by digestion with restriction enzymes. ZFY and ZFX transcripts were present in all stages examined following RT-PCR, whereas transcripts for SRY were undetectable in all investigated stages following either RT nested PCR or Southern analysis. The presence of ZFY transcripts suggests that Y chromosome is transcriptionally active during early ovine preimplantation development. The possible relationship between a faster growth of male embryos and the transcription of Y-linked genes at early stages of development is discussed.
由于雄性绵羊胚胎比雌性胚胎发育得更快，因此利用逆转录聚合酶链反应（RT-PCR）在植入前阶段检测了位于Y染色体上的两个基因SRY和ZFY的转录情况。从体外成熟和受精、然后在合成输卵管液培养基中培养的绵羊胚胎池中提取RNA，并在授精后24至207小时（从二细胞期直至孵化囊胚期）回收胚胎。由于用于扩增ZFY的引物也能扩增位于X染色体上的同源物ZFX，因此通过用限制性内切酶消化来区分转录本。RT-PCR后，在所检测的所有阶段均存在ZFY和ZFX转录本，而在RT巢式PCR或Southern分析后的所有研究阶段均未检测到SRY转录本。ZFY转录本的存在表明Y染色体在绵羊植入前早期发育过程中具有转录活性。本文讨论了雄性胚胎更快生长与发育早期Y连锁基因转录之间的可能关系。
