英漢對(duì)照分子生物學(xué)導(dǎo)論-Chapter-6課件(PPT 56頁)

1、Chapter 6 Translation / 翻譯第1頁，共56頁。Chapter 6 Translation / 翻譯6.1 The Genetic Code6.2 Mechanism of Translation in Prokaryotes6.3 Translation in Eukaryotes6.4 tRNA Structure and Wobble6.5 Experiments6.1 遺傳密碼6.2 原核生物翻譯機(jī)理6.3 真核生物翻譯6.4 tRNA結(jié)構(gòu)與搖擺6.5 實(shí)驗(yàn)研究第2頁，共56頁。6.1 The Genetic Code/ 遺傳密碼Translation: synt

2、hesis of a protein using an mRNA as the template.Transcription第3頁，共56頁。 tRNA: the converter第4頁，共56頁。 tRNA: the converter第5頁，共56頁。4 bases vs. 20 amino acidsUCAG GlyAla Ile Leu Met Phe Trp Pro Val SerThr Asn Gln Cys Tyr AspGlu Arg HisLys第6頁，共56頁。1 base 1 amino acidUCAG GlyAla Ile Leu Met Phe Trp Pro V

3、al SerThr Asn Gln Cys Tyr AspGlu Arg HisLys第7頁，共56頁。2 bases 1 amino acidUUUCUAUGGlyAla Ile Leu Met Phe Trp Pro Val SerThr Asn Gln Cys Tyr AspGlu Arg HisLysCUCCCACGAUACAAAGGUGCGAGG第8頁，共56頁。3 bases 1 amino acid第9頁，共56頁。The genetic code / 遺傳密碼第10頁，共56頁。6.2 Mechanism of Translation in Prokaryotes原核生物翻譯機(jī)

4、理6.2.1 Initiation / 起始6.2.2 Elongation / 延伸6.2.3 Termination / 終止第11頁，共56頁。Composition of prokaryotic ribosome原核生物核糖體的組成第12頁，共56頁。6.2.1 Initiation / 起始IF-1DissociationIF-3No reassociationSeparation of 30S and 50S subunits第13頁，共56頁。SD sequence: the translation start signal第14頁，共56頁。16S rRNA3 end第15頁，

5、共56頁。The 30s initiation complex30S起始復(fù)合體The collection of the 30S subunit, the mRNA, and the initiator tRNA is called the 30S initiation complex.第16頁，共56頁。The initiator tRNA第17頁，共56頁。The 70S initiation complex第18頁，共56頁。The 70S ribosome第19頁，共56頁。6.2.2 Elongation / 延伸1) tRNA entering2) Peptidyl transfe

6、r3) Translocation4) tRNA leaving第20頁，共56頁。1) tRNA entering / tRNA進(jìn)入第21頁，共56頁。2) Peptidyl transfer / 肽基轉(zhuǎn)移第22頁，共56頁。3) Translocation / 移位第23頁，共56頁。4) tRNA leaving / tRNA離開第24頁，共56頁。Elongation factors / 延伸因子Weaver, Molecular Biology, Chapter 18第25頁，共56頁。Elongation factors / 延伸因子Weaver, Molecular Biolog

7、y, Chapter 18第26頁，共56頁。6.2.3 Termination / 終止Translation terminates when ribosome reaches a stop codon, because there is no tRNA being able to bind to the stop codon.第27頁，共56頁。Now showingTranslation: the three stepsFile: biophoto7 Introduction to Genetic Analysis Translation: the three steps of tran

8、slation (5)第28頁，共56頁。6.3 Translation in Eukaryotes真核生物翻譯Composition of eukaryotic ribosome真核生物核糖體的組成第29頁，共56頁。Differences in Translation Initiation翻譯起始的不同點(diǎn)Initiator tRNA / 其始tRNAThe scanning model / 掃描模型第30頁，共56頁。1) Initiator tRNA / 其始tRNACAUAAnticodonfMet-tRNAfMet Formyl Met A C C5 AC AG CA* Alkyla

9、ted adenosineAnticodonMet-tRNAMet Met A C C5 AG CG CAG-引自：Turner, P. C. et al.分子生物學(xué)精要速覽（影印版），科學(xué)出版社，1999，p.249CAUProkaryotic initiator tRNAEukaryotic initiator tRNA第31頁，共56頁。Prokaryotic initiator tRNA 70S ribosome第32頁，共56頁。Eukaryotic initiator tRNA 80S ribosomeCH3第33頁，共56頁。Yeast 80S ribosomeFile: Yea

10、st 80S ribosome 1S1I.val 第34頁，共56頁。2) The scanning model / 掃描模型Prokaryotes:SD sequenceEukaryotes:Scanning model第35頁，共56頁。The scanning model / 掃描模型第36頁，共56頁。Translation initiated by entering IRES site directly通過直接進(jìn)入IRES位點(diǎn)啟動(dòng)翻譯IRES: internal ribosome entry sequence第37頁，共56頁。Picornavirus / 小核糖核酸病毒 www.u

11、niklinikum-giessen.de/./res_ires.htm Internal entryAUG第38頁，共56頁。Translation initiation in eukaryotes (1/4)eIFeukaryotic initiationfactor第39頁，共56頁。Translation initiation in eukaryotes (2/4)第40頁，共56頁。Translation initiation in eukaryotes (3/4)第41頁，共56頁。Translation initiation in eukaryotes (4/4)第42頁，共56

12、頁。6.4 tRNA Structure and WobbletRNA結(jié)構(gòu)與搖擺第43頁，共56頁。6.4.1 Anti-codons / 反密碼子第44頁，共56頁。Three-dimensional structure of a tRNA第45頁，共56頁。Aminoacyl-tRNA synthetase: a kind of enzyme that can recognize a tRNAs anticodon and match it with the correct amino acid. Aminoacyl-tRNA synthetase 氨酰tRNA合成酶第46頁，共56頁。A

13、minoacyl-tRNA synthetase53mRNACodon第47頁，共56頁。Show 3D: synthetase-tRNA complexFile: E coli Thr-tRNA Synthetase Complex 1QF6.valAnti-codonAmino acid第48頁，共56頁。6.4.2 Wobble / 搖擺第49頁，共56頁。Wobbling is possiblemRNAtRNADNA5555第50頁，共56頁。Wobbled base pairsBase at the first positionin the anticodonBases at the third positionin the codon U A, GG C, UI A, U, CTable 6.2 Allowed base pairings from wobble hypothesis表6.2 搖擺假說允許的堿基配對(duì)第51頁，共56頁。Wobbled base pairs第52頁，共56頁。6.5 Experiments / 實(shí)驗(yàn)研究6.5.1 Deciphering the genetic code 破譯遺傳密碼6.5.2 Direction of tran