MOLECULAR EVOLUTION OF REPTILES WITH EMPHASIS ON MECHANISMS OF SEX DETERMINATION

爬行动物的分子进化，重点是性别决定机制

• 批准号: 3755978
• 负责人: JOHN W ROBERTS
• 金额: --
• 依托单位: CALIFORNIA STATE UNIV-DOMINGUEZ HILLS
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3755978
• 关键词: Chelonia; Reptilia; alternatives to animals in research; animal ecology; biochemical evolution; environmental stressor; gene expression; genotype; molecular genetics; nucleic acid sequence; polymerase chain reaction; sex chromosomes; sex determination; snakes; southern blotting; temperature

Reptiles tend to be very conservative in karyotype, and yet have evolved a variety of mechanisms for sex determination, including genotypic sex determination of the XX/XY type, genotypic sex determination of the ZZ/ZW type, and environmental sex determination, where sex is determined by an environmental stimulus, such as incubation temperature during development. The proposed experiments have two main goals: a comparison of the molecular bases of different sex determination mechanisms in reptiles; and the use of DNA sequence data to construct phylogenetic relationships among certain groups of pit vipers. Southern blot hybridization will be used to look for sequences homologous to the mammalian sex determination gene, Sry, in genomic DNA from pit viper with genotypic sex determination, and from the desert tortoise, with environmental sex determination. If homologous sequences are detected, it will suggest that all mechanisms of sex determination are similar at the genetic level; this may contribute to our understanding of sex chromosome aneuploidy syndromes in humans. The pit vipers are responsible for a large fraction of snakebite injuries and fatalities. The proposed phylogenetic investigations might aid in the rational production and use of antivenins, and in the isolation of biomedically useful products. Student participants will gain a background in molecular genetics, and direct experience in performing a variety of techniques of recombinant DNA and general nuclei acid manipulation. After a training period, they will have the opportunity to conduct independent research, and thereby prepare for further graduate studies leading to a Ph.D. degree, and for careers as competitive biomedical research scientists.

爬行动物在核型中往往非常保守，但已经进化 性别确定的各种机制，包括基因型性别 XX/XY类型的确定，ZZ/ZW的基因型性别确定 类型和环境性别确定，性别是由性别决定的 环境刺激，例如发育过程中的孵化温度。 提出的实验有两个主要目标：比较 爬行动物中不同性别确定机制的分子碱基；和 使用DNA序列数据来构建系统发育关系 某些斗士组。 Southern印迹杂交将用于寻找同源的序列 从毒viper的基因组DNA中，哺乳动物性确定基因，sry sry 通过基因型的性别决定，以及从沙漠乌龟中 环境性别确定。 如果检测到同源序列，则 将表明，所有性别确定的机制在 遗传水平；这可能有助于我们对性染色体的理解 人类的非整倍性综合征。 坑蛇造成了很大一部分蛇咬的伤害 和死亡。 提出的系统发育研究可能有助于 理性生产和抗抗蛋白的使用，并隔离 生物美食有用的产品。 学生参与者将获得分子遗传学的背景，并且 直接执行各种重组DNA技术的经验 和一般核酸操纵。 经过培训期，他们将 有机会进行独立研究，从而准备 为了进一步的研究生研究，导致博士学位。学位，从事职业 竞争性生物医学研究科学家。