Mandon-Pépin Béatrice, Oustry-Vaiman Anne, Vigier Bernard, Piumi François, Cribiu Edmond, Cotinot Corinne
Unité Biologie du développement et Biotechnologies, INRA, 78350 Jouy en Josas, France.
Biol Reprod. 2003 Mar;68(3):985-95. doi: 10.1095/biolreprod.102.008557.
In female sheep fetuses, two of the most crucial stages of ovarian development are prophase of meiosis I and follicle formation. In the present study, sheep ovaries collected on Days 25, 38, 49, 56, 67, 75, 94, and 120 of gestation, at birth, and in adulthood were tested by reverse transcription-polymerase chain reaction (RT-PCR) for the expression of 14 genes known to be involved in the ovarian differentiation in diverse organisms. The aim of this study was to determine 1) the expression pattern of six genes involved in germ cell development or meiosis (DMC1, SPO11, MSH4, MSH5, DAZL, and Boule) and five ovary-derived factors (OVOL1, SIAH2, DIAPH2, FOXL2, and FGF9), 2) the onset of gene expression for several members of the bone morphogenetic protein (BMP) pathway involved in follicular development (GDF9, BMP15, BMPR-IB), and 3) the chromosomal localization of seven of these genes in the sheep genome. The RT-PCR analysis revealed that the two germline-specific genes, DAZL and Boule, were expressed between 49 and 94 days postcoitum (dpc) with a similar pattern to typical meiosis genes (DMC1, MSH4, and MSH5), suggesting their possible participation in prophase of meiosis I. GDF9 and OVOL1 gene transcription started at 56 dpc and extended until birth, while BMP15 presented a more restricted window of expression between 94 dpc and birth, corresponding to the formation of first growing follicles. The homologous ovine genes for SPO11, DMC1, MSH5, DAZL, FGF9, DIAPH2, and SIAH2 were located on OAR 13q21-22, 3q35, 20q22, 19q13, 10q15, Xq44, and 1q41-42, respectively. In sheep, quantitative trait loci affecting female reproductive capacities are currently being detected. The ontology and precise mapping of ovarian genes will be useful to identify potential candidate genes that might underlie these effects.
在雌性绵羊胎儿中，卵巢发育的两个最关键阶段是减数分裂I前期和卵泡形成。在本研究中，通过逆转录-聚合酶链反应（RT-PCR）检测了在妊娠第25、38、49、56、67、75、94和120天、出生时以及成年期采集的绵羊卵巢中已知参与不同生物体卵巢分化的14个基因的表达。本研究的目的是确定：1）参与生殖细胞发育或减数分裂的6个基因（DMC1、SPO11、MSH4、MSH5、DAZL和Boule）以及5个卵巢衍生因子（OVOL1、SIAH2、DIAPH2、FOXL2和FGF9）的表达模式；2）参与卵泡发育的骨形态发生蛋白（BMP）途径的几个成员（GDF9、BMP15、BMPR-IB）的基因表达起始时间；3）这些基因中的7个在绵羊基因组中的染色体定位。RT-PCR分析显示，两个种系特异性基因DAZL和Boule在交配后49至94天表达，其模式与典型的减数分裂基因（DMC1、MSH4和MSH5）相似，表明它们可能参与减数分裂I前期。GDF9和OVOL1基因转录在妊娠56天开始并持续到出生，而BMP15的表达窗口更窄，在妊娠94天至出生之间，对应于第一批生长卵泡的形成。SPO11、DMC1、MSH5、DAZL、FGF9、DIAPH2和SIAH2的同源绵羊基因分别位于绵羊13号染色体q21-22、3号染色体q35、20号染色体q22、19号染色体q13、10号染色体q15、X染色体q44和1号染色体q41-42上。在绵羊中，目前正在检测影响雌性繁殖能力的数量性状基因座。卵巢基因的本体论和精确图谱将有助于识别可能是这些效应基础的潜在候选基因。
