Artificial Chromosome construction and it's uses/Cytogenetics/Mutation Breeding/Plant Breeding/ Plant Genetics/

1. Artificial Chromosome construction
and it’s uses
Made by – Anchal Agarwal
Submitted to – Dr. Varsha
ma’am

2. INTRODUCTION
Artificial Chromosome:
Refers to any non integrating
Vector that is transmissible and has the ability to harbor
large amount of DNA.
Advantages-
1.) Used as a powerful mutagen.
2.) Used in gene stacking.
3.) Used in sequencing project.
4.) Used for mass production of multiple foreign genes.

3. In Bacteria – Circular
In yeast, animals and plants – Linear
First constructed in yeast and E.coli systems
Requirements for chromosomal maintenance and stability –
- Centromeres,
- Telomeres
- Origin of replication

4. NEED OF AC
• 1.) The transformation process often results in the integration of
foreign genes into an endogenous gene and disrupts it’s function
• 2.) Transgenes can be influenced by the upstream or
downstream regulatory material around them means position
effect.
• 3.) Aids in gene stacking or pyramiding.
• 4.) Used as Vector.
*Yeast Artificial Chromosome
*Bacterial Artificial Chromosome
*Human Artificial Chromosome

5. •Requirements for Synthetic Artificial Chromosome –
1. Centromere
2. Telomere
3. Sufficient Chromatin
4. Selectable Marker Transgene.

6. ARTIFICIAL CHROMOSOME AS A VECTOR
1.) YEAST ARTIFICIAL CHROMOSOME (YAC)
• YAC is a plasmid into which yeast genes have been inserted.
• Developed by Murray and Szostak in 1983.
• Capacity – 3000kb
• YAC- Largest capacity vectors available.
• Advantages – Can be used to express eukaryotic proteins
that requires post translation modification.
• Disadvantages – Less stable than BACs and show chimerism.

7. 2.) BACTERIAL ARTIFICIAL CHROMOSOME (BAC)
• Construction is based on f plasmid
• Capacity- 350kb
• Uses – used to sequence the genome of organism e.g., HGP
• Being utilized in modelling genetic disease – Alzheimer’s
disease
• Infectious viral clones – herpesviruses, poxviruses.
3.) HUMAN ARTIFICIAL CHROMOSOME (HAC)
*Synthetically produced vector DNA, possessing the character
of human Chromosoms.
• Used in gene therapy.

8. METHOD TO DEVELOP ARTIFICIAL CHROMOSOME
Bottom up Method Top down Method

9. BOTTOM UP METHOD
• Building Chromosomes by denovo assembling their
components parts
• Used for assembling of HAC
• Upon delivery DNA is subjected to rearrangements resulting
in AC larger than the original construct.
• Not yet used in plants due to high complexity and limited
understanding about plants about plant Centromere
organizations.

10. TOP – DOWN METHOD
• Based on chromosome fragmentation or truncation.
• Achieved by -Irradiation. (An unstable maize
miniisochromosome comprising part of the short arm of
chromosome 10 had been recovered as a result of Pollen
Irradiation.
- Telomere mediated truncation. (Use Telomere
repeats to Whittle away Chromosome arm , especially in
plants for constructing gene of interest.)