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Nucleic acids & Proteins. Molecular Genetics. َ At the end of this session, you should answer this questions: 1. What is DNA and its structure? 2. What is RNA and its types, structure and functions? 3. What is proteom?. DNA (Deoxyribonucleic acid). Nucleic acids: 1. DNA
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Molecular Genetics َ At the end of this session, you should answer this questions: 1. What is DNA and its structure? 2. What is RNA and its types, structure and functions? 3. What is proteom?
DNA (Deoxyribonucleic acid) • Nucleic acids: 1. DNA • 2. RNA • Including polymers called Poly nucleotides • Nucleotides: a phosphate molecule • a five-carbon sugar • (Deoxyribose or Ribose ) • a cyclic Nitrogen-containing base: • Purines: A, G • Pyrimidines: T, C, U
Bonding • 1. 5’-3’ phosphodiester linkages: • Chromosome 21: 50,000,000 bases • Chromosome 1: 250,000,000bases • 2. Hydrogen bonding: A-T, G-C
Watson-crick model (primary) The double-helix: horizontal rungs Right handed Antiparallel Secondary: Nucleosome Histone code: H2A, H2B, H3, H4 Tertiary: Solenoid or Chromatin fibers: rings: (Chromosome)
DNAماده وراثتي • Geneتوالي مشخص DNA براي توليد يك محصول • Chromosomeارگانل ژنتيكي • Genomeمجموعه ماده وراثتي يك گونه: 3,000,000,000 • Proteomeمجموعه ماده پرتئيني يك گونه
Gene structure • 1. Coding region: Exon • 2. Noncoding: Intron • 3. Regulatory elements: promoter • enhancer • silencer • boundary
RNA (Ribonucleic acid) • ساختمان RNA • > اختلافات DNA و RNA • > انواع RNA های موجود در سلول انسانی • > انتقال اطلاعات در سلول: اصل مركزي
RNA 1. FunctionalRNA (fRNA), non-coding (ncRNA), non-protein-coding RNA (npcRNA), non-messenger RNA (nmRNA): transfer RNA (tRNA) (rRNA) ribosomal RNA snoRNA, microRNA, siRNA, long ncRNAs,… 2. Non-functional RNA: RNA molecule that is translated to protein: mRNA
Transcriptome The set of all RNA molecules, including mRNA, rRNA, tRNA, and other non-coding RNA produced in one or a population of cells.
رونويسي Transcription DNA (Template, noncoding, antisense or non- transcribed strand): 5’-3’ strand DNA (Coding, sense or transcribed strand): 3’-5; RNA polymerase II “start site” of the UTR, 5’ side RNA transcription by: Cap to 5’ Cut in the downstream Poly A addition, polyadenylation: (...AAUAA..) 3’UTR between stop codon and polyA
RNA processing & splicing → mRNA Transport
ترجمه Translation • on the Ribosomes (rRNA & rProtein) • 3 bases (codon)→ aa • genetic code: 64→20, degenerate • initiator codon: met. • stop or nonsense codon • tRNA: aa+tRNA←A.tRNAs.(ATP) • anticodon
Protein assembly • Post-translation processing: • folding • mixing: Hb • chemical adding • cutting: proinsulin
پردازش در RNA • پردازش r RNA و t RNA • متیلاسیونRNA • RNases • rRNAهای S 18 و S 28 و S 8/5 • اتصال ملکولهای پیش ماده ی RNA به هم و تشکیل mRNA ی بالغ • پردازشmRNA • capping • توالی AAUAAA و polyA • splicing توسط spliceosome • splice donor - GU • splice acceptor - AG • branch point • ساختمان نهاییmRNA بالغ
Proteins • - Proteome: cells, organelles, organs. • 1,000,000 pr.s from 25,000 human genes: • Alternative splicing, biochemical modification • - Important roles in diseases: • Hemophilia • PKU • BRCA1 • Cystic fibrosis
Proteins 1. Housekeeping 2. Specialty Protein organelles and disease location: - Secondary effects: PKU - Limited effects on housekeeping proteins: Genetic redundancy Specific affect: Tay-Sachs - Rarely in every tissues: actin or DNA polymerase: no compatible with live birth.
سنتز پروتئین شارژ شدن یك tRNA ریبوزومها زیر واحد s40 از حدود 30 تشکیل شده زیر واحد s60 دارای 50 پروتئین است شروع پروتئین سازی فاكتور های شروع و اتصال IF2 بهGTP تشکیل كمپلكس tRNA-MET-GTP-IF2 ادامه و پایان پروتئین سازی آمینواسیل tRNA ها فاكتورهای طویل کننده (EF1) وGTP فاكتور آزاد كننده یاRF) ) پپتیدیل ترانسفراز
1. What is DNA and its structure? 2. What is RNA and its types, structure and functions? 3. What is proteom?