GENE REGULATION OXYTOCIN The following gene is from
- Slides: 57
GENE REGULATION
OXYTOCIN • The following gene is from m. RNA that has been copied with reverse transcriptase to produce c. DNA • Sequence provided is from the coding strand
1 accagtcacg gaccctggac ccagcgcaccatgg ccggccccag cctcgcttgc 61 tgtctgctcg gcctcctggc gctgacctcc gcctgctaca tccagaactg ccccctggga 121 ggcaagaggg ccgcgccgga cctcgacgtg cgcaagtgcc tcccctgcgg ccccgggggc 181 aaaggccgct gcttcgggcc caatatctgc tgcgcggaag agctgggctg cttcgtgggc 241 accgccgaag cgctg ccaggaggag aactacctgc cgtcgccctg ccagtccggc • 301 cagaaggcgt gcgggagcgg gggccgctgc gcggtcttgg gcctctgctg cagcccggac • 361 ggctgccacg ccgaccctgcgacgcg gaagccacct tctcccagcg ctgaaacttg • 421 atggctccga acaccctcga agcgcgccac tcgcttcccc catagccacc ccagaaatgg • 481 tgaaaataaagcagg tttttctcct ct
SIGNAL SEQUENCE • 37 -93 • Before signal sequence is the leader sequence • Mature Oxytocin 94 -120 27 nucleotides = 9 amino acids
• Preproprotein 37 - 411 • Signal seq, oxytocin + neurophysin I Proprotein 94 -411 Oxytocin + neurophysin I • Mature Peptides modified from Proprotein • Trailer sequence responsible for Poly. A-polymerase action
1 accagtcacg gaccctggac ccagcgcaccatgg ccggccccag cctcgcttgc 61 tgtctgctcg gcctcctggc gctgacctcc gcctgctaca tccagaactg ccccctggga 121 ggcaagaggg ccgcgccgga cctcgacgtg cgcaagtgcc tcccctgcgg ccccgggggc 181 aaaggccgct gcttcgggcc caatatctgc tgcgcggaag agctgggctg cttcgtgggc 241 accgccgaag cgctg ccaggaggag aactacctgc cgtcgccctg ccagtccggc • 301 cagaaggcgt gcgggagcgg gggccgctgc gcggtcttgg gcctctgctg cagcccggac • 361 ggctgccacg ccgaccctgcgacgcg gaagccacct tctcccagcg ctgaaacttg • 421 atggctccga acaccctcga agcgcgccac tcgcttcccc catagccacc ccagaaatgg • 481 tgaaaataaagcagg tttttctcct ct
Notice the 1 st 3 nucleotides… • CODING STRAND ATG TEMPLATE STRAND TAC m. RNA AUG…start codon Amino Acid Methionine (Met)
tgc tac atc cag aac tgc ccc ctg gga acg atg tag gtc ttg acg ggg gac cct ugc uac auc cag aac ugc ccc cug gga Cys-tyr-ile-gln-asn-cys-pro-leu-gly
WOBBLE EFFECT • rd 3 base of t. RNA may form H -bonds with more than 1 kind of nucleotide • Ie AAU and AAC Asn
TRANSCRIPTION FACTORS
RECOGNIZE SEQUENCES • Transcription factors recognize DNA sequences inorder to target specific genes
ROLE OF REGULATORY PROTEINS • Transcription factors are genetic switches • Master Genes ie HOX genes code for transcription factors • Related “Regulatory Proteins” in prokaryotes
PROKARYOTIC REGULATION • No hormonal regulation • No introns no splicing • No capping/tailing • Coupled transcription/translation
• Constitutive – always on; can be regulated (enzymes in glycolysis) • Inducible – off but can be switched on • Repressible – on but can be switched off
OPERONS • Cluster of genes in which expression is regulated by operatorrepressor protein interactions, operator region, and the promoter. • Promoter • Repressor • Operator (controlling site) • Coding sequences • Terminator
Lac Operon • Lactose is an inducer • “Inducible” operon • Negative regulation
– -galactosidase (lac. Z) • Breaks lactose into glucose + galactose. • Converts lactose to the allolactose, regulates lac operon. –Lactose permease (lac. Y) • Transports lactose across cytoplasmic membrane. –Transacetylase (lac. A)
• Positive control when lactose is E. coli’s sole carbon source (but not if glucose also is present). • Catabolite activator protein (CAP) binds c. AMP, activates, and binds to a CAP recognition site upstream of the promoter (c. AMP is greatly reduced in presence of glucose).
• CAP changes the conformation of DNA and facilitates binding of RNA polymerase and transcription. • When glucose and lactose are present, E. coli preferentially uses glucose due to low levels of active CAP (low c. AMP).
• Regulation of the trp operon: • “repressible” gene • 1. Repressor/operator interaction • When tryptophan is present, tryptophan binds to trp. R gene product. • trp. R protein binds to the trp operator and prevents transcription.
• Is TRP operon neg or pos regulation? • What type of regulation controls repressors/inducers?
Jacob and Monod • What is true for E. coli is also true for the elephant!
GENETIC SWITCHES • A switch includes. . a) Binding protein b) Binding protein recognizes a strecth of DNA
Significance? • Mutate the gene encoding the transcription factor or the DNA sequence to which it binds and gene expression can be altered!
GENE INACTIVATION • 1. CHROMATIN structure – Heterochromatin (tight– gene off) vs Euchromatin (loose – gene on) • 2. Methylation – adding methyl group to inactivate genes on DNA • 3. small RNA affects chromatin structure / interferes with transcription (RNAi system)
Methylation • Reinforces inactivation • Involved in Barr-Body (inactive X chromosome)
TRANSCRIPTIONAL CONTROL • Signals (hormones) in eukaryotes • Environmental- heat shock proteins • Regulator proteins (Transcription factors) – bind to TATA (like prokaryotes) • UPEs (Upstream Promoter Elements) – increase efficiency of RNA pol.
Example… • Glucocorticoids released by stress bind to steroid receptor (in liver) forms complex binds to DNA activates genes involved in gluconeogenesis
Weakly transcribed
Strongly transcribed
• TRANSLATIONAL CONTROL • CAPPING – 7’ methyl guanosine added to 5’ role in initiation/ protection • Poly A tail protection, promotes transport out of Nucleus • Splicing – Introns removed Exons for code
• Differential m. RNA processing –Cells in each tissue produce own version of m. RNA –For example, different forms of troponin, a protein that regulates muscle contraction, produced in different muscle tissue
• POST TRANSLATIONAL • modification of polypeptide (ie reduction in size of proinsulin to insulin) • chemical modification – addition of phosphate (Kinases) removal of phosphate (Phosphatases)
• Examine the insulin pathway as a form of gene regulation
- Differential gene regulation
- Chapter 12 section 4: gene regulation and mutations
- Section 4 gene regulation and mutation
- Chapter 18: regulation of gene expression
- Chapter 18 regulation of gene expression
- "manuales delorenzo"
- Repressible operon
- What is a positive and negative control
- What is gene regulation
- Prokaryotes vs eukaryotes gene regulation
- Chapter 18 regulation of gene expression
- Section 12-5 gene regulation
- Gene regulation
- Chapter 18 regulation of gene expression
- Section 12-5 gene regulation answer key
- Regulation of gene expression
- Oxytocin storage
- Uterine stimulants definition
- Oxytocin
- Nurses responsibility of oxytocin
- Oxytocin action
- Amiformes
- Partogram who guidelines
- Tocolytic drugs
- Oxytocin calculation
- Oxytocin is secreted by
- Oxytocin
- Oxytocin
- Gene by gene test results
- Chapter 17 from gene to protein
- Tia chieu sa te
- Một số thể thơ truyền thống
- Thế nào là hệ số cao nhất
- Sơ đồ cơ thể người
- Tư thế ngồi viết
- Số nguyên là gì
- đặc điểm cơ thể của người tối cổ
- Các châu lục và đại dương trên thế giới
- Mật thư tọa độ 5x5
- Tư thế worm breton
- ưu thế lai là gì
- Thẻ vin
- Cái miệng bé xinh thế chỉ nói điều hay thôi
- Các châu lục và đại dương trên thế giới
- Bổ thể
- Từ ngữ thể hiện lòng nhân hậu
- Tư thế ngồi viết
- Thứ tự các dấu thăng giáng ở hóa biểu
- Làm thế nào để 102-1=99
- Thơ thất ngôn tứ tuyệt đường luật
- Hát lên người ơi alleluia
- Hươu thường đẻ mỗi lứa mấy con
- đại từ thay thế
- Diễn thế sinh thái là
- Vẽ hình chiếu vuông góc của vật thể sau
- Công của trọng lực
- Thế nào là mạng điện lắp đặt kiểu nổi