a brief discription about gene exprssion and regulation at a basics level

1. GENE EXPRESSION AND
REGULATION
Vinoth Kumar V
17-PZO-010

2. What is Gene Expression?
 It is the process by which information from a
gene is used in the synthesis of a functional
gene product mostly proteins, but in non-protein
coding genes such as rRNA genes or tRNA
genes also occurs.

3. Basic Understandings and why should i
study gene expression:
 Both of these cells contain the
same genome, but they express
different RNAs and proteins.
 Complexity of protein formation.
 Necessary for extended knowledge
about related pathways
Involved in gene
expression.

4. Classification of gene
• Constitutive ( house keeping) genes:
• housekeeping genes are typically
constitutive genes that are required for the
maintenance of basic cellular function, and are
expressed in all cells of an organism under normal
and patho-physiological conditions.eg ubiquitin
• Controllable genes:
• 1- Are expressed only as needed. Their amount
may increase or decrease with respect to either
responsive to environmental change or dependent
on the position in the cell cycle.eg cyclin.eg lac.

5. Control of gene expression can be:

6. When the expression of genetic is quantitatively increased by
the presence of specific regulatory element is known as
positive regulation.
Element modulating positive regulation is known as activator
when the expression of genetic information diminished by the
presence of specific regulatory element is known as negative
regulation.
The element or molecule mediating the negative regulation is
said to be repressor.
Regulation of gene expRession is of two
types

7.  Regulation of gene expression (or gene
regulation):
 Gene regulation is essential for viruses,
prokaryotes and eukaryotes as it increases the
versatility and adaptability of an organism by
allowing the cell to express protein when needed.
 Furthermore, gene regulation drives the
processes of cellular differentiation and
morphogenesis, leading to the creation of
different cell types in multicellular organisms
where the different types of cells may possess
different gene expression profile.

8. Principles of Gene Regulation:
Most prokaryotic genes are regulated in
units called operons.
Francois Jacob & Jacques Monod, 1961.
This is largely based on regulation of lactose
metabolism. By intestinal bact. E.coli.

9. Gene regulatory protein’s structural motifs:

11. Pro karyo tic / Eukaryo tic

12. OPERON in gene regulation of prokaryotes:
In genetics, an operon is a functioning unit of genomic
DNA containing a cluster of genes under the control of a
single promoter.
Operons occur primarily in prokaryotes but also in some
eukaryotes.
An operon is made up of several structural genes
arranged under a common promoter and regulated by a
common operator.

13. General structure of an OPERON

15. PRESENCE AND ABSENCE OF LACTOSE:

17. OThER REguLATiONS:

20. Eukaryotic gEnE rEgulation
occurs at sEvEral lEvElslEvEls:

21. HistonE modifications:
1) DNA methylation:

22. 2)DNA acetylation:

24. Control at transcription initiationControl at transcription initiation
regulation by RNA polymerase:

26. rna procEssingrna procEssing::

27. Control at mRNA splicingControl at mRNA splicing

28. Regulation by miRNARegulation by miRNA

29. Regulation by protein stability
• Protein molecule is tagged for degradation by
attachment of a 20 kDa protein, ubiquitin

33. THANK YOU!!!!!!THANK YOU!!!!!!