鼠标Sry位所含的一个神秘的外因子,对于男性的性别确定至关重要.
在PubMed上查看摘要
概括
此摘要是机器生成的。新发现的鼠标性别决定基因Sry (Sry-T) 的第二个外基因是男性发育的真正因素. 这一发现重新定义了我们对Sry基因功能和哺乳动物性别决定的理解.
科学领域
- 遗传学
- 发育生物学
- 哺乳动物的性别确定
背景情况
- 这种Sry基因对于哺乳动物的男性性别决定至关重要.
- 在过去的30多年里,Sry一直被认为是一个单元基因.
研究的目的
- 识别Sry基因的新型转录和功能.
- 调查潜在的两种表细胞Sry转录在性别决定中的作用.
主要方法
- 在小鼠Sry基因中识别出一个神秘的第二个外基因.
- 在XY和XX小鼠中Sry-T转录的分析.
- Sry-T和Sry-S蛋白表达和稳定性的比较.
主要成果
- 在小鼠中发现了两种表原体的Sry转录 (Sry-T).
- 缺乏Sry-T的XY小鼠表现出性别逆转,这表明它对男性发育的必要性.
- 在XX小鼠中诱导雄性发育的Sry-T表达.
- 由于没有降解蛋白,SRY-T蛋白比SRY-S更稳定.
结论
- SRY-T,而不是正规的SRY-S,是小鼠的主要丸决定因素.
- 斯里的第二个前基因可能最近在小鼠中演化,包含了逆转移子衍生的序列.
- 这一发现需要对已建立的哺乳动物性别测定模型进行修订.
相关概念视频
The Y chromosome is a sex chromosome found in several vertebrates and mammals, including humans. In addition to 22 pairs of autosomes, the human males have one X chromosome and one Y chromosome. In these organisms, the presence or absence of the Y chromosome determines the development of male traits.
Evolution
Around 300 million years ago, the two sex chromosomes diverged from two identical autosomal chromosomes. Over time, the Y chromosome has lost most of its genes, shrinking in size....
In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female...
In animals, gender is determined by the number and type of sex chromosome. For example, human females have two X chromosomes, and males have one X and one Y chromosome, whereas C.elegans with one X chromosome is a male, and the one with two X chromosomes is a hermaphrodite.
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will...
Among mammals, the gender of an organism is determined by the sex chromosomes. Humans have two sex chromosomes, X and Y. Every human diploid cell has 22 pairs of autosomes and one pair of sex chromosomes. A human female has two X chromosomes, while a male has one X chromosome and one Y chromosome.
The germline cells such as egg and sperm cells carry only half the number of chromosomes, i.e., 22 autosomes and one sex chromosome. All eggs have an X chromosome, while sperm cells can carry an X or...
Development of the reproductive organs in an embryo starts from a bipotential state. This means the early embryo can develop either male or female reproductive organs. The formation of these organs begins with the growth of gonadal ridges that arise from the intermediate mesoderm during the fifth week of development.
Near the gonadal ridges, two duct systems are present: the mesonephric ducts (Wolffian ducts) and paramesonephric ducts (Müllerian ducts). These ducts form the basis for the...
In most mammalian species, females have two X sex chromosomes and males have an X and Y. As a result, mutations on the X chromosome in females may be masked by the presence of a normal allele on the second X. In contrast, a mutation on the X chromosome in males more often causes observable biological defects, as there is no normal X to compensate. Trait variations arising from mutations on the X chromosome are called “X-linked”.
One well-studied example of an X-linked trait is...

