SlideShare a Scribd company logo
Holliday Model
Muhammad Saeed Siddiqui
BOT-19-27
Holiday Model of Recombination
• Discovered by Robin Holliday in 1964 in E. Coli
• Explain heteroduplex formation and gene conversion
during recombination.
• Although it has been supplanted by double strand
break model, it provides a base for understanding.
• It illustrates the critical steps of pairing of homologus
duplexes, formation of a heteroduplex, formation of
recombination joints, branch migration and
Resolution.
• Duplex
• Double stranded DNA molecule, generated
by base pairing between complimentary single strands.
• Belong to same source
• Heteroduplex
• Double stranded DNA molecule, generated
by base pairing between complimentary single strands.
• Double strands derived from different
parental duplex molecule.
• Occurs during genetic recombination.
Steps
1. Alignment
2. Nick formation (endo-nucleases)
3. Strand invasion and ligation (heteroduplex
formation)
4. Holliday junction/ Holliday fork/ Holliday
intermediate/ chi-structure.
5. Branch migration
6. Junction is resolved
7. Recombination
Alignment
Nick Formation
Nick
Endo-Nucleases cuts single strand of each homologus DNA at the same position
5’
5’
5’
5’
3’
3’
3’
3’
Chain Invasion
• Helicase and SSB Protein, which open the strand and migrate each open
strand to the other DNA molecule. Then Ligase enzyme attaches both
open strands.
5’ 3’
3’ 5’
3’ 5’
5’ 3’
Migration
• Branch migration occurs which forms the heteroduplex.
5’ 3’
3’ 5’
3’ 5’
5’ 3’
Resolve of Junction
• Duplex pulled away from one another. And rotate at
180 degree. Resolvase (RuvC), Ligase, gyrase and Pol.
5’ 3’
3’
5’
3’
5’
3’
5’
Animation
Vertical Cut and Horizontal Cut
Non-Crossover Crossover
Holliday Model of DNA Recombination

More Related Content

What's hot

Mitochondrial genome and its manipulation
Mitochondrial genome and its manipulationMitochondrial genome and its manipulation
Mitochondrial genome and its manipulation
Avinash Gowda H
 
Homologous recombination
Homologous recombinationHomologous recombination
Homologous recombination
AnkushYadav65
 
Dna repair
Dna repairDna repair
Dna repair
pravee14
 
DNA TOPOLOGY
DNA TOPOLOGYDNA TOPOLOGY
DNA TOPOLOGY
Anu Sreejith
 
Genetic recombination mechanism
Genetic recombination mechanismGenetic recombination mechanism
Genetic recombination mechanism
Nepalgunj Medical College and Teaching Hospital
 
Chloroplast dna
Chloroplast dnaChloroplast dna
Chloroplast dna
nj1992
 
Second genetic code overlapping and split genes
Second genetic code overlapping and split genesSecond genetic code overlapping and split genes
Second genetic code overlapping and split genes
gohil sanjay bhagvanji
 
Molecular basis of mutations
Molecular basis of mutationsMolecular basis of mutations
Molecular basis of mutations
Shalini Saini
 
Cot curve
Cot curve Cot curve
Cot curve
EmaSushan
 
Transformation in bacteria
Transformation in bacteriaTransformation in bacteria
Transformation in bacteria
vibhakhanna1
 
Transposons ppt
Transposons pptTransposons ppt
Transposons ppt
Zeeshan Ahmed
 
Complementation of defined mutations
Complementation of defined mutationsComplementation of defined mutations
Complementation of defined mutations
Somashree Das
 
Site specific recombination
Site specific recombinationSite specific recombination
Site specific recombination
Roshan Parihar
 
Transposable elements
Transposable elementsTransposable elements
Transposable elements
Sai Kiran Munagala
 
Tryptophan operon
Tryptophan operonTryptophan operon
Tryptophan operon
devadevi666
 
Dna repair mechanisms
Dna repair mechanismsDna repair mechanisms
Dna repair mechanisms
ShariqaJan
 
Restriction Mapping
Restriction MappingRestriction Mapping
Restriction Mapping
Sunil Bhandari
 
DNA Replication in eukaryotes and prokaryotes
DNA Replication in eukaryotes and prokaryotesDNA Replication in eukaryotes and prokaryotes
DNA Replication in eukaryotes and prokaryotes
Mohammad Barshan
 
Tetrad analysis by rk
Tetrad analysis by rkTetrad analysis by rk
Tetrad analysis by rk
Ranjeettaram
 
cDNA Library
cDNA LibrarycDNA Library
cDNA Library
Syed Muhammad Khan
 

What's hot (20)

Mitochondrial genome and its manipulation
Mitochondrial genome and its manipulationMitochondrial genome and its manipulation
Mitochondrial genome and its manipulation
 
Homologous recombination
Homologous recombinationHomologous recombination
Homologous recombination
 
Dna repair
Dna repairDna repair
Dna repair
 
DNA TOPOLOGY
DNA TOPOLOGYDNA TOPOLOGY
DNA TOPOLOGY
 
Genetic recombination mechanism
Genetic recombination mechanismGenetic recombination mechanism
Genetic recombination mechanism
 
Chloroplast dna
Chloroplast dnaChloroplast dna
Chloroplast dna
 
Second genetic code overlapping and split genes
Second genetic code overlapping and split genesSecond genetic code overlapping and split genes
Second genetic code overlapping and split genes
 
Molecular basis of mutations
Molecular basis of mutationsMolecular basis of mutations
Molecular basis of mutations
 
Cot curve
Cot curve Cot curve
Cot curve
 
Transformation in bacteria
Transformation in bacteriaTransformation in bacteria
Transformation in bacteria
 
Transposons ppt
Transposons pptTransposons ppt
Transposons ppt
 
Complementation of defined mutations
Complementation of defined mutationsComplementation of defined mutations
Complementation of defined mutations
 
Site specific recombination
Site specific recombinationSite specific recombination
Site specific recombination
 
Transposable elements
Transposable elementsTransposable elements
Transposable elements
 
Tryptophan operon
Tryptophan operonTryptophan operon
Tryptophan operon
 
Dna repair mechanisms
Dna repair mechanismsDna repair mechanisms
Dna repair mechanisms
 
Restriction Mapping
Restriction MappingRestriction Mapping
Restriction Mapping
 
DNA Replication in eukaryotes and prokaryotes
DNA Replication in eukaryotes and prokaryotesDNA Replication in eukaryotes and prokaryotes
DNA Replication in eukaryotes and prokaryotes
 
Tetrad analysis by rk
Tetrad analysis by rkTetrad analysis by rk
Tetrad analysis by rk
 
cDNA Library
cDNA LibrarycDNA Library
cDNA Library
 

Recently uploaded

Constructing Your Course Container for Effective Communication
Constructing Your Course Container for Effective CommunicationConstructing Your Course Container for Effective Communication
Constructing Your Course Container for Effective Communication
Chevonnese Chevers Whyte, MBA, B.Sc.
 
Walmart Business+ and Spark Good for Nonprofits.pdf
Walmart Business+ and Spark Good for Nonprofits.pdfWalmart Business+ and Spark Good for Nonprofits.pdf
Walmart Business+ and Spark Good for Nonprofits.pdf
TechSoup
 
คำศัพท์ คำพื้นฐานการอ่าน ภาษาอังกฤษ ระดับชั้น ม.1
คำศัพท์ คำพื้นฐานการอ่าน ภาษาอังกฤษ ระดับชั้น ม.1คำศัพท์ คำพื้นฐานการอ่าน ภาษาอังกฤษ ระดับชั้น ม.1
คำศัพท์ คำพื้นฐานการอ่าน ภาษาอังกฤษ ระดับชั้น ม.1
สมใจ จันสุกสี
 
Leveraging Generative AI to Drive Nonprofit Innovation
Leveraging Generative AI to Drive Nonprofit InnovationLeveraging Generative AI to Drive Nonprofit Innovation
Leveraging Generative AI to Drive Nonprofit Innovation
TechSoup
 
Film vocab for eal 3 students: Australia the movie
Film vocab for eal 3 students: Australia the movieFilm vocab for eal 3 students: Australia the movie
Film vocab for eal 3 students: Australia the movie
Nicholas Montgomery
 
How to Make a Field Mandatory in Odoo 17
How to Make a Field Mandatory in Odoo 17How to Make a Field Mandatory in Odoo 17
How to Make a Field Mandatory in Odoo 17
Celine George
 
Traditional Musical Instruments of Arunachal Pradesh and Uttar Pradesh - RAYH...
Traditional Musical Instruments of Arunachal Pradesh and Uttar Pradesh - RAYH...Traditional Musical Instruments of Arunachal Pradesh and Uttar Pradesh - RAYH...
Traditional Musical Instruments of Arunachal Pradesh and Uttar Pradesh - RAYH...
imrankhan141184
 
How to Setup Warehouse & Location in Odoo 17 Inventory
How to Setup Warehouse & Location in Odoo 17 InventoryHow to Setup Warehouse & Location in Odoo 17 Inventory
How to Setup Warehouse & Location in Odoo 17 Inventory
Celine George
 
Bed Making ( Introduction, Purpose, Types, Articles, Scientific principles, N...
Bed Making ( Introduction, Purpose, Types, Articles, Scientific principles, N...Bed Making ( Introduction, Purpose, Types, Articles, Scientific principles, N...
Bed Making ( Introduction, Purpose, Types, Articles, Scientific principles, N...
Leena Ghag-Sakpal
 
UGC NET Exam Paper 1- Unit 1:Teaching Aptitude
UGC NET Exam Paper 1- Unit 1:Teaching AptitudeUGC NET Exam Paper 1- Unit 1:Teaching Aptitude
UGC NET Exam Paper 1- Unit 1:Teaching Aptitude
S. Raj Kumar
 
Liberal Approach to the Study of Indian Politics.pdf
Liberal Approach to the Study of Indian Politics.pdfLiberal Approach to the Study of Indian Politics.pdf
Liberal Approach to the Study of Indian Politics.pdf
WaniBasim
 
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem studentsRHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
Himanshu Rai
 
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UP
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPLAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UP
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UP
RAHUL
 
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptxNEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
iammrhaywood
 
Beyond Degrees - Empowering the Workforce in the Context of Skills-First.pptx
Beyond Degrees - Empowering the Workforce in the Context of Skills-First.pptxBeyond Degrees - Empowering the Workforce in the Context of Skills-First.pptx
Beyond Degrees - Empowering the Workforce in the Context of Skills-First.pptx
EduSkills OECD
 
Your Skill Boost Masterclass: Strategies for Effective Upskilling
Your Skill Boost Masterclass: Strategies for Effective UpskillingYour Skill Boost Masterclass: Strategies for Effective Upskilling
Your Skill Boost Masterclass: Strategies for Effective Upskilling
Excellence Foundation for South Sudan
 
ANATOMY AND BIOMECHANICS OF HIP JOINT.pdf
ANATOMY AND BIOMECHANICS OF HIP JOINT.pdfANATOMY AND BIOMECHANICS OF HIP JOINT.pdf
ANATOMY AND BIOMECHANICS OF HIP JOINT.pdf
Priyankaranawat4
 
spot a liar (Haiqa 146).pptx Technical writhing and presentation skills
spot a liar (Haiqa 146).pptx Technical writhing and presentation skillsspot a liar (Haiqa 146).pptx Technical writhing and presentation skills
spot a liar (Haiqa 146).pptx Technical writhing and presentation skills
haiqairshad
 
Gender and Mental Health - Counselling and Family Therapy Applications and In...
Gender and Mental Health - Counselling and Family Therapy Applications and In...Gender and Mental Health - Counselling and Family Therapy Applications and In...
Gender and Mental Health - Counselling and Family Therapy Applications and In...
PsychoTech Services
 
Mule event processing models | MuleSoft Mysore Meetup #47
Mule event processing models | MuleSoft Mysore Meetup #47Mule event processing models | MuleSoft Mysore Meetup #47
Mule event processing models | MuleSoft Mysore Meetup #47
MysoreMuleSoftMeetup
 

Recently uploaded (20)

Constructing Your Course Container for Effective Communication
Constructing Your Course Container for Effective CommunicationConstructing Your Course Container for Effective Communication
Constructing Your Course Container for Effective Communication
 
Walmart Business+ and Spark Good for Nonprofits.pdf
Walmart Business+ and Spark Good for Nonprofits.pdfWalmart Business+ and Spark Good for Nonprofits.pdf
Walmart Business+ and Spark Good for Nonprofits.pdf
 
คำศัพท์ คำพื้นฐานการอ่าน ภาษาอังกฤษ ระดับชั้น ม.1
คำศัพท์ คำพื้นฐานการอ่าน ภาษาอังกฤษ ระดับชั้น ม.1คำศัพท์ คำพื้นฐานการอ่าน ภาษาอังกฤษ ระดับชั้น ม.1
คำศัพท์ คำพื้นฐานการอ่าน ภาษาอังกฤษ ระดับชั้น ม.1
 
Leveraging Generative AI to Drive Nonprofit Innovation
Leveraging Generative AI to Drive Nonprofit InnovationLeveraging Generative AI to Drive Nonprofit Innovation
Leveraging Generative AI to Drive Nonprofit Innovation
 
Film vocab for eal 3 students: Australia the movie
Film vocab for eal 3 students: Australia the movieFilm vocab for eal 3 students: Australia the movie
Film vocab for eal 3 students: Australia the movie
 
How to Make a Field Mandatory in Odoo 17
How to Make a Field Mandatory in Odoo 17How to Make a Field Mandatory in Odoo 17
How to Make a Field Mandatory in Odoo 17
 
Traditional Musical Instruments of Arunachal Pradesh and Uttar Pradesh - RAYH...
Traditional Musical Instruments of Arunachal Pradesh and Uttar Pradesh - RAYH...Traditional Musical Instruments of Arunachal Pradesh and Uttar Pradesh - RAYH...
Traditional Musical Instruments of Arunachal Pradesh and Uttar Pradesh - RAYH...
 
How to Setup Warehouse & Location in Odoo 17 Inventory
How to Setup Warehouse & Location in Odoo 17 InventoryHow to Setup Warehouse & Location in Odoo 17 Inventory
How to Setup Warehouse & Location in Odoo 17 Inventory
 
Bed Making ( Introduction, Purpose, Types, Articles, Scientific principles, N...
Bed Making ( Introduction, Purpose, Types, Articles, Scientific principles, N...Bed Making ( Introduction, Purpose, Types, Articles, Scientific principles, N...
Bed Making ( Introduction, Purpose, Types, Articles, Scientific principles, N...
 
UGC NET Exam Paper 1- Unit 1:Teaching Aptitude
UGC NET Exam Paper 1- Unit 1:Teaching AptitudeUGC NET Exam Paper 1- Unit 1:Teaching Aptitude
UGC NET Exam Paper 1- Unit 1:Teaching Aptitude
 
Liberal Approach to the Study of Indian Politics.pdf
Liberal Approach to the Study of Indian Politics.pdfLiberal Approach to the Study of Indian Politics.pdf
Liberal Approach to the Study of Indian Politics.pdf
 
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem studentsRHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
 
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UP
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPLAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UP
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UP
 
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptxNEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
 
Beyond Degrees - Empowering the Workforce in the Context of Skills-First.pptx
Beyond Degrees - Empowering the Workforce in the Context of Skills-First.pptxBeyond Degrees - Empowering the Workforce in the Context of Skills-First.pptx
Beyond Degrees - Empowering the Workforce in the Context of Skills-First.pptx
 
Your Skill Boost Masterclass: Strategies for Effective Upskilling
Your Skill Boost Masterclass: Strategies for Effective UpskillingYour Skill Boost Masterclass: Strategies for Effective Upskilling
Your Skill Boost Masterclass: Strategies for Effective Upskilling
 
ANATOMY AND BIOMECHANICS OF HIP JOINT.pdf
ANATOMY AND BIOMECHANICS OF HIP JOINT.pdfANATOMY AND BIOMECHANICS OF HIP JOINT.pdf
ANATOMY AND BIOMECHANICS OF HIP JOINT.pdf
 
spot a liar (Haiqa 146).pptx Technical writhing and presentation skills
spot a liar (Haiqa 146).pptx Technical writhing and presentation skillsspot a liar (Haiqa 146).pptx Technical writhing and presentation skills
spot a liar (Haiqa 146).pptx Technical writhing and presentation skills
 
Gender and Mental Health - Counselling and Family Therapy Applications and In...
Gender and Mental Health - Counselling and Family Therapy Applications and In...Gender and Mental Health - Counselling and Family Therapy Applications and In...
Gender and Mental Health - Counselling and Family Therapy Applications and In...
 
Mule event processing models | MuleSoft Mysore Meetup #47
Mule event processing models | MuleSoft Mysore Meetup #47Mule event processing models | MuleSoft Mysore Meetup #47
Mule event processing models | MuleSoft Mysore Meetup #47
 

Holliday Model of DNA Recombination

  • 1.
  • 2. Holliday Model Muhammad Saeed Siddiqui BOT-19-27
  • 3. Holiday Model of Recombination • Discovered by Robin Holliday in 1964 in E. Coli • Explain heteroduplex formation and gene conversion during recombination. • Although it has been supplanted by double strand break model, it provides a base for understanding. • It illustrates the critical steps of pairing of homologus duplexes, formation of a heteroduplex, formation of recombination joints, branch migration and Resolution.
  • 4. • Duplex • Double stranded DNA molecule, generated by base pairing between complimentary single strands. • Belong to same source • Heteroduplex • Double stranded DNA molecule, generated by base pairing between complimentary single strands. • Double strands derived from different parental duplex molecule. • Occurs during genetic recombination.
  • 5. Steps 1. Alignment 2. Nick formation (endo-nucleases) 3. Strand invasion and ligation (heteroduplex formation) 4. Holliday junction/ Holliday fork/ Holliday intermediate/ chi-structure. 5. Branch migration 6. Junction is resolved 7. Recombination
  • 7. Nick Formation Nick Endo-Nucleases cuts single strand of each homologus DNA at the same position 5’ 5’ 5’ 5’ 3’ 3’ 3’ 3’
  • 8. Chain Invasion • Helicase and SSB Protein, which open the strand and migrate each open strand to the other DNA molecule. Then Ligase enzyme attaches both open strands. 5’ 3’ 3’ 5’ 3’ 5’ 5’ 3’
  • 9. Migration • Branch migration occurs which forms the heteroduplex. 5’ 3’ 3’ 5’ 3’ 5’ 5’ 3’
  • 10. Resolve of Junction • Duplex pulled away from one another. And rotate at 180 degree. Resolvase (RuvC), Ligase, gyrase and Pol. 5’ 3’ 3’ 5’ 3’ 5’ 3’ 5’
  • 12. Vertical Cut and Horizontal Cut Non-Crossover Crossover