分子生物学英文课件：Eukaryote gene and genome

1、Molecular Biology Genetic Information,中心法则 (The Central Dogma),Transcription,Translation,Reverse transcription,Replication,DNA,RNA,蛋白质,Gene expression: DNAmRNAProtein DNA RNA,Gene expression: DNAmRNAProtein DNA RNA,translation,transcription,真核基因与基因组,Chapter 3,Eukaryote Gene and Genome,真核基因的结构与功能,第一节

2、,The Structure and Function of Eukaryote Gene,Gene: Gene are DNA fragments that carry the special genetic information includes the entire nucleic acid sequence necessary for the expression of its product (peptide or RNA). Functional units of a DNA molecule (or, in a few cases, RNA) A chromosomal or

3、mitochondrial DNA segment codes the information required to produce a functional biological product Have unique structure elements,+1,转录起点,+N,转录终点,转录,AUG,UAA,翻译起点,翻译终点,翻译,结构基因区,调控区,-N,5,3,N,C,基因,mRNA,蛋白质,Gene expression: DNAmRNAProtein DNA RNA,转录,翻译,mRNA mRNA tRNA rRNA mRNA,The function of genes,DNA

4、 is the genetic material that stores the genetic information for protein synthesis or RNA. The exact duplication (replication) of this information in any species from generation to generation assures the genetic continuity of that species. Gene expression (Transcription & Translation) determines the

5、 structure and function of protein, thus controls identifiable traits of an organism. RNA carries out the instructions encoded in DNA, and participate in the whole process of gene expression in all cells. RNA is also the genetic material of some viruses.,The structure of eukaryotic genes,Coding sequ

6、ence : exons coding for protein or RNA,Non-coding sequence : introns and un-transcribed regulatory sequence required for modulation of a gene expression, including promoter, enhancer,Split gene: eukaryotic structure gene consists of several coding regions and non-coding regions that are spaced and i

7、nlaid one other.,Exon: segments of eukaryotic gene (or of the primary transcript of that gene) that are saved as part of a functional, mature mRNA, rRNA or tRNA molecules. Intron: segments of eukaryotic gene (or of the primary transcript of that gene) that are removed by splicing during RNA processi

8、ng and are not included in the mature, functional mRNA, rRNA, or tRNA.,The structure of eukaryotic genes,-,+,三、调控序列参与真核基因表达调控,真核基因组的结构与功能,第二节,The Structure and Function of Eukaryote Genome,Genome: the total genetic material that contains an organisms all genetic information. Eukaryotic genome is com

9、posed of the chromosomal and mitochondrial DNA Only a small fraction of the genomic DNA is in coding sequences for 25,000 genes Contains multiple repeated sequences,Repetitive sequences,高度重复序列（highly repetitive sequence） 中度重复序列（moderately repetitive sequence） 单拷贝序列（single copy sequence）或低度重复序列,（一）高度

10、重复序列（highly repetitive sequence）,Satellite DNA is the main component of functional centromeres, and form the main structural constituent of heterochromatin.,consists of short lengths of less than 10 base pairs that are repeated millions of (106 ) times per cell.,反向重复序列（inverted repeat sequence）,卫星DN

11、A（satellite DNA）,a sequence ofnucleotidesfollowed downstream by itsreverse complement.The intervening sequence of nucleotides between the initial sequence and the reverse complement can be any length including zero. When the intervening length is zero, the composite sequence is apalindromic sequence.,形成,5AAACCACCGCTGGTAGCGGTGGTTT3 3TTTGGTGGCGACCATCGCCACCAAA5,反向重复序列（inverted repeat sequence）,（二）中度重复序列（moderately repetitive sequence）,in lengths up to a few hundred base pairs that are repeated at least 1,000 (103 104)times,（三）单拷贝序列（single copy sequence）或低度重复序列,consists of unique segments an