文档介绍：25. Extranuclear Inheritance(cytoplasmic inheritance)
What is Extranuclear Inheritance ?
How is it produced ?
characteristics?
Particles ,Mt and pt ?
Application ?
25 Extranuclear Inheritance
Commonly defined as transmission through the cytoplasm (or things in the cytoplasm, anelles) rather than the nucleus
Generally only one parent contributes
Extranuclear Inheritance
Organelle anelles that contain chromosomes
Chloroplasts and mitochondria
Infectious heredity
Involves a symbiotic or parasitic association with a anism
Maternal effect
Nuclear gene products are stored in ooplasm and distributed to cells as the fertilized egg divides to form developing embryo
高等生物除了核内作为主要的遗传体系对生物性状的遗传与个体的生长发起着决定性的作用
还有另外的遗传体系——线粒体、叶绿体,除了决定自身功能之外,还与核内体系相互、共同作用,实现特定的功能。
一些共生颗粒,如质粒、卡巴等虽没有明确而必须的功能,但也产生表型效应。
染色体以外的遗传因子所决定的遗传现象,在真核生物中称为核外遗传或细胞质遗传(extranuclear Inheritance或cytoplasmic inheritance
Chloroplasts and Mitochondria
anelles contain DNA
First explanation for [some] maternal inheritance patterns
Endosymbiont theory
Analysis of mutant alleles anelles can plex because many genes ponents are nuclear-encoded
And even subunits of a ponent enzyme may be partially encoded in both locations
Heteroplasmy makes things even worse…
草履虫放毒型的遗传(细胞内敏感性物质)
放毒现象与内共生体
线粒体的遗传
叶绿体的遗传
禾谷类作物的雄性不育
核外遗传的物质基础
细胞质基因组
或核外基因组
细胞器基因组
细菌质粒
共生生物
1 母体影响
2 核外遗传的性质与特点
3 细胞内敏感物质的遗传
4 线粒体的遗传方式及其分子基础
5 叶绿体遗传及其分子基础
6 核外与雄性不育性
第一节母性影响(maternal effects)
通常,核内遗传的特点是,两亲本贡献相等的遗传物质,正交 AA x aa或反交 aa x AA,子代表现一样的。可是有时两种交配结果并不相同,子代的表型受母亲(母本)基因型的影响而和母亲表型一样,这种现象称为母性影响母性影响
分为:
短暂的母性影响
持久的母性影响
Contrasts to Non-Mendelian ics Maternal Effect
Animation: Maternal Effect
Some maternally-derived phenotypes are produced by the maternal nuclear genome (maternal effect), rather than inherited as extranuclear genes (maternal inheritance).
a. Proteins and/or mRNA deposited in the oocyte before fertilization direct early development in the embryo.
b. The genes encoding these products are on nuclear chromosomes. No mtDNA is invo