09-P056 Identification and characterisation of chicken DMRT1 transcript isoforms
09-P056 Identification and characterisation of chicken DMRT1 transcript isoforms
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09-P056 鸡 DMRT1 转录亚型的鉴定和表征
DOI：
10.1016/j.mod.2009.06.386
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发表时间：
2009
影响因子：
2.6
通讯作者：
Zhao D
中科院分区：
文献类型：
--
作者：
Zhao D
在鸟类中，性别决定的机制尚不清楚：雌性特异性W染色体是否编码类似于哺乳动物睾丸决定基因的卵巢决定基因，或者睾丸决定是否依赖于逃避失活的Z染色体基因的双倍剂量。此外，鸟类不携带Sry基因的同源物，并且所提出的性别决定基因的身份是未知的。目前，被认为是“经典”睾丸决定基因的最强鸟类候选基因是DMRT 1（double-blind和Mab-3相关转录因子1）。DMRT 1在脊椎动物中是保守的，在哺乳动物、鸟类、爬行动物和鱼类的发育性腺中表达，在雄性性腺中的表达高于雌性性腺。鸡DMRT 1位于Z染色体上，在疑似性别决定点（第5.5天/第28阶段）和之后，在雄性（ZZ）性腺中的表达水平高于雌性（ZW）性腺。最近，我们在鸡中鉴定了六种不同的DMRT 1转录本亚型。对这些cDMRT 1 cDNA的序列分析表明，它们编码DM结构域（一个保守的锌指样DNA结合结构域）和/或SP结构域（一个功能未知的保守结构域）的组合。5个不同的5 'UTR序列的鉴定表明5个不同的转录起始位点。PolyA北方分析显示，从第5天到第9天，一种转录物在雄性胚胎性腺中的表达水平高于雌性胚胎性腺。目前，已经产生了带有cDMRT 1的转基因鸡，进一步的分析正在进行中。
In birds, the mechanism of sex determination is unknown: it is uncertain whether the female-specific W-chromosome encodes an ovary-determining gene analogous to the mammalian testis-determining gene, or whether testis determination is dependent on a double dose of a Z-chromosome gene (s) that escapes inactivation. In addition, birds do not carry a homologue to the Sry gene and the identity of the proposed sex determining gene is unknown. Currently, the gene considered the strongest avian candidate for a'classical'testis-determining gene is DMRT1 (doublesex and Mab-3-related transcription factor 1). DMRT1 is conserved across vertebrates and is expressed in the developing gonads of mammals, birds, reptiles and fish, with higher expression in male than in female gonads. Chicken DMRT1 is located on the Z-chromosome and is expressed at higher levels in male (ZZ) gonads than in female (ZW) gonads, both at and after the suspected point of sex determination (day 5.5/stage 28). Recently we have identified six different transcript isoforms of DMRT1 in the chicken. Sequence analysis of these cDMRT1 cDNAs revealed that they encode a combination of DM domain (a conserved zinc-finger-like DNA-binding domain) and/or a SP domain (conserved domain with unknown function). The identification of five different 5'UTR sequences indicates five different transcription initiation sites. PolyA Northern analysis shows that one transcript is expressed at higher levels in male embryonic gonad than in female embryonic gonad from day 5 to 9. Currently, a transgenic chicken with cDMRT1 has been generated and further analysis is underway.