Cloning Vectors

Cloning Vectors

Quarter 3 Module 5

MELCs

• Classify the different types of cloning vectors

• Describe a plasmid and its uses in recombinant DNA technology

• Cite the importance of recombinant DNA technology

What are cloning vectors?

It refers to a DNA molecule which is used as a vehicle to artificially carry foreign genetic material into another cell where it can be replicated or expressed

Essential Characteristics of a Cloning Vector

• It must be self-replicating inside the host cell

• It must possess a unique restriction site for restriction enzymes

• The introduction of donor DNA fragments must not interfere with the replication property of the vector

• It must possess some marker gene such that it can be used for later identification of recombinant cell

• It should be easily isolated from the host

Plasmids

• Extra chromosomal circular double stranded DNA replicating element found in bacterial cells

• It is inserted into bacterial cells in a process called transformation

• Generally carries a marker gene which is mostly a gene for antibiotic resistance

Bacteriophage

• This is a virus that infects a bacteria

• This is an intracellular obligate parasite that multiply inside a bacterial cell by making use of some or all of the host's enzyme

• Most of its genome is non-essential and can be replaced with foreign DNA

Bacterial Artificial Chromosomes (BAC)

• These are simple plasmids designed to clone a very large DNA fragments

• They have markers and very stable origin of replication that promotes the distribution of plasmid after bacterial cell division

• They are basically used in sequencing the genome of the organism

Yeast Artificial Chromosomes (YAC)

• Mostly used for cloning very large fragments and for physical mapping of complex genomes

• Known to produce chimeric effects

• Less stable compared to BACs

Human Artificial Chromosomes (HAC)

• A micro-chromosome that can act as a new chromosome in a population of human cells