0:00
Hello. My name is Lian Scott,
and I'm recording
this talk today
on behalf of Doctor Esam Yahya,
Lecturer in Bioprocess Division,
School of Industrial Technology,
University Sains, Malaysia.
Today I'll be talking about
the delivery of genes
and nucleotides,
which is a potentially
powerful approach
to stem cell biology,
tissue engineering,
genetic research,
and gene therapy,
by altering the behavior
of targeted cells.
0:27
The human body consists of
around 30 trillion cells.
Each cell normally contains
23 pairs of chromosomes,
22 are called autosomes,
and one pair of sex chromosomes.
Most DNA is in the cell nucleus
within these chromosomes,
and a small amount of DNA is
found in the mitochondria.
These 23 pairs of chromosomes
consist of DNA in a form of
two linked strands that wind
around each other to resemble
a twisted ladder shape,
known as a double helix,
and attached with a scaffold of
proteins known as histones.
Each strand has a
backbone made of
alternating deoxyribose
sugar and phosphate groups.
Attached to each sugar is
one of four bases: adenine,
cytosine, guanine, or thymine.
Together, they are
called nucleotides.
The sequence of the bases
of each nucleotide along
the DNA's backbone encodes
biological information,
such as the
instructions for making
a protein or RNA molecule.
1:24
A gene is a segment of
DNA on a chromosome that
forms the basic physical and
functional unit of heredity.
Some genes act as instructions
to make proteins,
while others do not
code for any protein,
and act as regulatory genes.
Genes can also be classified
into protein coding genes,
and RNA-coding genes.
Protein coding genes are
transcribed into messenger RNA,
and then translated to
functional proteins.
While RNA-coding genes are
transcribed to a
functional non-coding RNA,
such as transfer RNAs,
ribosomal RNAs, and microRNAs.
In humans, genes
vary in size from
a few hundred DNA bases to
up to two million bases,
depending on the
function of these genes.
