在陆地植物中,KNOX2基因调节了从平分体到二分体的形态过渡
Keiko Sakakibara1, Sayuri Ando, Hoichong Karen Yip
1Department of Biological Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Japan. bara@hiroshima-u.ac.jp
Science (New York, N.Y.)
|March 2, 2013
概括
陆地植物交替地在平分体体细胞和二分体体球体细胞的几代之间. 2类结结1-Like HOMEOBOX (KNOX2) 转录因子防止在双胞胎阶段形成平分体体图,这对于这种交替至关重要.
科学领域:
- 植物生物学 植物生物学
- 发育遗传学的发展遗传学.
- 进化生物学是进化的生物学.
背景情况:
- 陆地植物表现出几代人的交替,具有明显的多细胞平体 (双体) 和双体 (双胞体) 体.
- 这些代人由独立的发育计划来调节,由化或受精开始.
- 主导的一代有所不同,青青为体育植物和血管植物为体育植物.
研究的目的:
- 研究KNOTTED1-LIKE HOMEOBOX (KNOX2) 类2转录因子对陆地植物代代相交调节的作用.
- 了解平体和双体阶段之间如何保持不同的发育计划.
主要方法:
- 在中进行基因分析 *Physcomitrella patens*.
- 删除2类KNOX2转录因子.
- 对双胞胎胚胎发育变化的观察.
主要成果:
- 在*Physcomitrella patens*中删除KNOX2导致从双胞胎胚胎中形成细胞体.
- 这种发展发生在没有平分化正常过程的情况下.
- 证明KNOX2蛋白在双胞胎阶段抑制了单胞胎特异性身体计划.
结论:
- 类2的KNOX2转录因子在防止双胞胎形细胞体内发展的双胞胎形细胞体规划方面发挥着至关重要的作用.
- 在陆地植物中,KNOX2功能的演变对于建立代代交替至关重要.
- KNOX2 作为一个关键的调节器,维持了两代人独特的发育路径.
相关概念视频
02:38Asexual Reproduction
Asexual reproduction allows plants to reproduce without growing flowers, attracting pollinators, or dispersing seeds. Offspring are genetically identical to the parent and produced without the fusion of male and female gametes.
02:19Morphogenesis
Plant morphogenesis—the development of a plant’s form and structure—involves several overlapping developmental processes, including growth and cell differentiation. Precursor cells differentiate into specific cell types, which are organized into the tissues and organ systems that make up the functional plant.
02:13Overview of Transposition and Recombination
Transposons make up a significant part of genomes of various organisms. Therefore, it is believed that transposition played a major evolutionary role in speciation by changing genome sizes and modifying gene expression patterns. For example, in bacteria, transposition can lead to conferring antibiotic resistance. Movement of transposable elements within the genetic pool of pathogenic bacteria can aid in transfer of antibiotic-resistant genetic elements. In eukaryotes, transposons can carry out...
02:50Dosage Compensation
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 have...
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 have...
01:57Meiosis II
Meiosis II is the second and final stage of meiosis. It relies on the haploid cells produced during meiosis I, each of which contain only 23 chromosomes—one from each homologous initial pair. Importantly, each chromosome in these cells is composed of two joined copies, and when these cells enter meiosis II, the goal is to separate such sister chromatids using the same microtubule-based network employed in other division processes. The result of meiosis II is two haploid cells, each containing...
02:02Meiosis II
Meiosis II entails cell division and segregation of the sister chromatids, resulting in the production of four unique haploid gametes. The steps for meiosis II are similar to mitosis, except that meiosis II occurs in haploid cells, whereas mitosis occurs in diploid cells.
The timing and cell division patterns of meiosis differ between males and females. In male meiosis, the centrosomes are part of the formation of the meiotic spindle. However, in oocytes, including that of humans, Drosophila,...
The timing and cell division patterns of meiosis differ between males and females. In male meiosis, the centrosomes are part of the formation of the meiotic spindle. However, in oocytes, including that of humans, Drosophila,...