Gene regulation is how a cell controls which genes, out of the many genes in its genome, are "turned on" (expressed). Thanks to gene regulation, each cell type in your body has a different set of active genes – despite the fact that almost all the cells of your body contain the exact same DNA. you can dowenload the interactive powerpoint through this link: https://docs.google.com/presentation/d/1Flqis6oX3Tq7nbRAiRcE71DTYcQ2TDkl/edit?usp=sharing&ouid=107152891770522030883&rtpof=true&sd=true

1. REGULATION
OF GENE
EXPRESSION

2. INTRODUCTION
01
DEFINITION
02
STEPS
03
PROKARYOTIC /
LAC OPERON
04
IMPORTANCE /
DISEASES
05
ENDING
06

3. INTRODUCTION
01

4. is a long DNA molecule
with part or all of the
genetic material of an
organism
Chromosome

5. DNA
is chemical basis of heredity
& regarded as reserve bank of
genetic information,
composed of functional units,
genes.

6. TYPES OF GENES
Constitutive genes (House keeping
genes): Expressed at a reasonably
constant rate Not subjected to
regulation eg: enzymes of glycolysis.
Regulated genes expressed only under
certain conditions expressed in all cells
/ subset of cells eg: expression of
insulin gene in panereas.

7. 4500
35000
Total genes number in
prokaryotes
Total genes number in
Eukaryotes

8. refers to the total
genetic information
contained in a cell.
Genome

9. WHOA!
So there are many genes
in every cell right? So
how cells differ ?!

10. How don't we have eyes on
our feet ,mouth on our
stomach ? How everything is
maintained?!
That's could been you!

11. So....
Without the existing
of regulation of gene
expression

12. DEFINATION
02

13. Gene expression is the process by
which the genetic code – the
nucleotide sequence – of a gene is
used in the synthesis of a functional
gene product.
● It refers to a complex series of
processes in which the
information encoded in a gene is
used to produce a functional
product such as a protein that
dictates cell function.
WHAT IS REGULATION OF
GENE EXPRESSION?

14. It involves several different
steps through which DNA is
converted to an RNA which
in turn is converted into a
protein or in some cases
RNA, for example, genes
encoding the necessary
information for transfer
RNAs and ribosomal RNAs
(tRNAs and rRNAs).

15. RNA
DNA
The two main stages include:
Transcription:the production of
messenger RNA (mRNA) by the
enzyme RNA polymerase, and the
processing of the resulting mRNA
molecule.
Translation: the use of mRNA to direct
protein synthesis, and the subsequent
post-translational processing of the
protein molecule.
Thus, gene expression is the
phenotypic manifestation of a gene or
genes by the processes of genetic
transcription and genetic
translation.
PROTEIN

16. RNA
DNA
PROTEIN

17. A. Positive Regulation:-
When the expression of genetic information is
quantitatively increased by the presence of specific
regulatory element, it is called as positive
regulation. The element or molecule mediating
positive regulation is called positive regulator.
NOTE: A double negative has the effect of acting as
a positive. An effector that inhibits the function of a
negative regulatory appears to
bring about a positive regulation.

18. B- Negative Regulation:-
When the expression of genetic information is
quantitatively decreased by the presence of specific
regulatory element, it is called as negative
regulation.
The element or molecule mediating negative
regulation is called negative regulator.

19. STEPS
03

20. Key steps involved in gene expression
include the following:
Transcription – conversion of DNA to RNA this is the first step
in gene expression in which DNA molecules are transcribed into
their corresponding RNA copy.
This process is aided by an enzyme called DNA-dependent RNA
polymerase.
Post-transcriptional modifications
In this process, the primary RNA obtained after
transcription is modified to produce a mature
messenger RNA or mRNA

21. Splicing Capping
The processes involved are:
RNA
transport
Translation
3
NH3
H
H
N
N
O
1
H
N
N
N
N
H
H2N
5
H2N
N
N
H—N
N
H
O
2
O
H3C
H
H—N
N—H
O
3
H2N
N
N
H—N
N
H
O
6
NH3
H
H
N
N
O
Protein folding
and
modifications
Tailing

22. Splicing
Capping
The processes involved are:
1
H
N
N
N
N
H
H2N
2
O
H3C
H
H—N
N—H
O
which is the cleavage of introns (non-
coding sequences) and ligation of exons
(coding sequences) with the help of
several components that recognize
specific sequences in the RNA.
which involves addition of a cap molecule
to the 5’ end

23. The processes involved are:
RNA
transport
3
NH3
H
H
N
N
O
3
H2N
N
N
H—N
N
H
O
Tailing
Most of the mature mRNAs produced after
modifications are transported from the
nucleus to the cytoplasm where the next
step in gene expression takes place.
This is achieved by moving the mRNAs
through tiny pores in the nucleus to reach
the cytosol.which
which is the addition of poly A tail to the 3’
end.

24. The processes involved are:
Translation
5
H2N
N
N
H—N
N
H
O
The sequence in the mRNA is
translated into a protein with the
help of several components such as
ribosomes, tRNAs or transfer RNAs,
and enzymes called aminoacyl tRNA
synthetases.
Translation of mRNA involves 3
important steps – initiation,
elongation, and termination, leading
to the formation of polypeptide
chains.

25. The processes involved are:
6
NH3
H
H
N
N
O
Protein folding
and
modifications
In this final step, the polypeptide chains or
random coils formed during translation
fold into a 3D structure giving rise to a
functional protein.
Failure to fold leads to protein inactivity
and misfolded proteins have abnormal
functionalities compared to correctly
folded ones.
Also, proteins can be modified by various
methods such as phosphorylation,
glycosylation, ADP ribosylation,
hydroxylation, and addition of other
groups.

26. 04
Prokaryotic / lac
operon

27. COMPARISON PROKARYOTIC AND
EUKARYOTIC GENE EXPRESSSION
FEATURES ProkaryotIc Eukaryotic
FUNCTION
Process by which information
from the prokaryotic genes is
used in the synthesis of a
functional gene product
Process by which information
from eukaryotic genes is used
in the synthesis of a functional
STRUCTURAL Occurs in the cytoplasm
Transcription occurs inside the
nucleus and translation occurs
in the cytoplasm
COMPOSITION
Transcription and translation
occur simultaneously
Transcription and translation
are temporally segregated
PROPAGATION
Prokaryotic DNA is not in
permanently condensed form
Eukaryotic DNA forms a stable,
condensed complex

28. Operon is defined as a segment of a DNA
strand consisting of:
• Structure genes: A cluster of several
structural genes, which carries the codons
which can be translated into proteins.
• Operator genes: One operator gene
which has an overall control over the
process of translation.
Gene Expression in
Prokaryotes Operon:

29. Gene Expression in Prokaryotes
Operon:
• Regulator gene: A third gene called regulator gene is
located sometimes at a distance from the operator gene on
the same DNA strand.
V Regulator gene transcribe m-RNA which synthesizes
"repressor protein" molecules which regulate the
transcription.
•P site (promoter site): is situated between operator gene
regulator gene.

30. Lactose (Lac) operon
*The "lac operon" is an inducible
catabolic operon of E.coli.
VIt consists of: 1. Structural genes: It
carries three structural genes 'Z', 'Y &
'A'. v Code respectively for "B-
galactosidase", "galactoside
permease" & "thiogalactoside
transacetylase".Operon
LAC Operon:

31. Lac Operon:
Functions: o B-galactosidase: hydrolyzes lactose (B-
galactoside) to galactose and glucose. o Permease:
responsible for the transport of lactose into the cell. o
Acetylase: coded by 'A' gene is not known properly. > The
structural genes Z, Y & A transcribe to form a single large m-
RNA with three independent translation units for te synthesis
of the three distinct enzymes. > Such a m-RNA coding for
more than one protein is called "polycistronic m-RNA" which
is characteristics in prokaryotes.•

33. “Our own genomes carry the story
of evolution, written in DNA, the
language of molecular genetics and
the narrative is unmistakable .”
—KENNETH R. MILLER

34. 05
IMPORTANCE AND
DISEASES

35. Importance of regulation of Gene
Expression
1-By altering gene
expression,
organisms can adapt
to environmental
challenges.
2-Transcription
control can result
in tissue specific
gene expression.
3-Gene regulation is
influenced by
hormones, heavy
metals and
chemicals.
4-Dysregulation of
gene regulation can
lead to disease.

36. Diseases
Furthermore, chemically
induced changes in gene
regulation are associated with
serious and complex human
diseases, including cancer,
diabetes and obesity,
infertility, respiratory
diseases, allergies, and
neurodegenerative disorders
such as Parkinson and
Alzheimer diseases.

37. We created in a sequence an
ordered sequence the least
thing we can say about it that
it's almost like a rhyme a
beautiful one Each part of it
connected
THANKS!