【医药健康】核外遗传即细胞质遗传共17页

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Section 4 Inheritance and molecular mechanism of
mitochondrion
➢ Mitochondrion genome character (mtDNA)
核外遗传因子存在于线粒体或叶绿体 基因组中,它们能够自主复制,通过细胞 质由一代传到另一代
遗传传递行为不按核基因的方式进行, 杂交子代中往往只表现母方的性状,杂 交后所合成的合子其细胞质几乎来自 雌性配子,雄性配子只提供一个核(染色 体)
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Section 3 Sensitive substance inheritance in cell
• 母性影响:子代表型不由自身的基 因决定而与母本表型相同的现象
• 短暂的母性影响 • 持久的母性影响
YANGTZE NPOeRrMmALaUnNIeVEnRStITmY aternal inheritance
Dextrol shell (dominance D) versus sinistral shell (recessiveness d) in Limnaea peregra
• Infective inheritance in Drosophila • Sigma(σ) • Sex ratio(SR)
• 草履虫卡巴粒(κ)的遗传 • 卡巴粒通过细胞质传递,但它的保持要依赖于
核基因(K)的存在,kk个ቤተ መጻሕፍቲ ባይዱ细胞质中的κ不能保 持和增殖 • 果蝇的感染性遗传 • σ颗粒 • 性比(SR)现象
➢ Naked DNA double-helix, non-repetitive DNA sequences, short polynucleotide sequences, semiconservative replication byθ, D loop, as well as rolling loop, the synthetic regulation independent on that of nuclear DNA, and the replication controlled by nuclear genes
Filial phenotypes are not determined by their genotypes, but by their maternal genotypes
transient maternal inheritance
permanent maternal inheritance
• 核外遗传:即细胞质遗传,真核生物 中染色体以外的遗传因子所决定 的遗传现象
椎实螺外壳右旋(D)对左旋(d)显性
P♀
X
♂
DD
F1
dd Dd
F2
Dextrol 全右旋
F3
3:1
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Nature and characteristics of cytoplasmic inheritance
核外遗传的性质和特点
Cytoplasmic genetic factors reside on mitochondrion or chloroplast DNA, replicate by themselves, and pass from one generation to the next through cytoplasm
The inheritance pattern is inconsistent with that of nuclear genes. Filial phenotypes are determined by maternal characters. The cytoplasm of a zygote derives from the female gamete while the male gamete provides only nuclear chromosomes
• •
• •
Extranuclear inheritance
Cytoplasmic inheritance, genetic factors in cytoplasm control the hereditary phenomenon in eukaryote.
Maternal inheritance
细胞内敏感性物质的遗传
• The inheritance pattern of Kappa particles in Paramecium aurelia
• κ particles transfer by cytoplasm, maintain by nuclear gene K, and can not maintain as well as proliferate an individual with genotype kk
【医药健康】核外遗传即细胞质遗传
16、云无心以出岫，鸟倦飞而知还。 17、童孺纵行歌，斑白欢游诣。 18、福不虚至，祸不易来。 19、久在樊笼里，复得返自然。 20、羁鸟恋旧林，池鱼思故渊。
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Extranuclear inheritance
色氨酸(tryptophan) A 犬尿氨酸(kynurenine) • →色素(pigment) → 卵细胞中积累(pigment • in the egg cell)→灰色(gray)
➢ Mitochondrion transcription and translation
➢ Mitochondrion is not all indepent for its heredity function. mtDNA can pass to the offspring, transcript to mRNA, and translate to polypeptides in mitochondrion. Mitochondrion has 55S to 80S ribosomes consisted of two subunits, each with a rRNA transcripted by mtDNA. There existed difference in genetic codes between mitochondrion and nucleus. Organellas such as mitochondrion are controlled by both the nuclear genome and mitochondrion genome