GENERAL IDEA OF SIGNAL TRANSDUCTION
DEFINATION
WHAT DOES THE TERM SIGNAL TRANSDUCTION MEANS
HISTORY
BASIC ELEMENTS IN SIGNAL TRANSDUCTION
TYPES OF SIGNAL TRANSDUCTION
SIGNALLING MOLECULE
RECEPTOR MOLECULE
MODES OF CELL CELL SIGNALING
SECOND MESSENGER
SIGNAL TRANSDUCTION PATHWAY
SOME SIGNALING PATHWAYS
SIGNIFICANCE
CONCLUSION
REFERENCE
ntroduction
2. Definition
3. Steps Of Signal Transduction
A) Reception
B) Transduction
C) Induction
4. Important component used in Signal Transduction
A) Calcium ion as second messenger
B) Protein Kinase
Types of Signal Transduction
A) Extra cellular Signal Transduction
B) Intra cellular Signal Transduction
C) Inter cellular Signal Transduction
6. Mechanism of Signal Transduction
A) GPCR pathway
B) RTK pathway
7. Example of Signal Transduction
A) In plants
B) In animals
8. Conclusion
9. Reference…
ntroduction
2. Definition
3. Steps Of Signal Transduction
A) Reception
B) Transduction
C) Induction
4. Important component used in Signal Transduction
A) Calcium ion as second messenger
B) Protein Kinase
Types of Signal Transduction
A) Extra cellular Signal Transduction
B) Intra cellular Signal Transduction
C) Inter cellular Signal Transduction
6. Mechanism of Signal Transduction
A) GPCR pathway
B) RTK pathway
7. Example of Signal Transduction
A) In plants
B) In animals
8. Conclusion
9. Reference…
G Proteins - Dr. P. Saranraj, Assistant Professor, Department of Microbiology, Sacred Heart College (Autonomous), Tirupattur, Vellore District, Tamil Nadu, India.
Introduction
Definition
History
Basic element in signal transduction
Basic Pathway of signal transduction
Types of signal transduction
Second messenger
Pathway of signal transduction
Conclusion
References
The signal transduction pathway uses a network of interactions within cells, among cells, and throughout plant.
The external signals that affect plant growth and development include many aspects of the plant’s physical, chemical, and biological environments. Some external signals come from other plants.
Many signals interact cooperatively and synergistically with each other to produce the final response. Signal combinations that induce such complex plant responses include red and blue light, gravity and light, growth regulators and mineral nutrients .
For example the overall regulation of seed germination involves control by both external factors and internal signals.
G Proteins - Dr. P. Saranraj, Assistant Professor, Department of Microbiology, Sacred Heart College (Autonomous), Tirupattur, Vellore District, Tamil Nadu, India.
Introduction
Definition
History
Basic element in signal transduction
Basic Pathway of signal transduction
Types of signal transduction
Second messenger
Pathway of signal transduction
Conclusion
References
The signal transduction pathway uses a network of interactions within cells, among cells, and throughout plant.
The external signals that affect plant growth and development include many aspects of the plant’s physical, chemical, and biological environments. Some external signals come from other plants.
Many signals interact cooperatively and synergistically with each other to produce the final response. Signal combinations that induce such complex plant responses include red and blue light, gravity and light, growth regulators and mineral nutrients .
For example the overall regulation of seed germination involves control by both external factors and internal signals.
Molecular interaction, Regulation and Signalling receptors and vesiclesAnantha Kumar
1. Overview of Extracellular signalling
2. Signalling molecules operate over various distance in animals
3.Endocrine Signalling
4.Paracrine Signalling
5.Autocrine Signalling
6. Signalling by Plasma membrane attached proteins
7.Receptors
8 Properties of receptors
9.Cell surface receptors belong to four major classes
10.Signal transduction Mechanism
11. Second messenger
12. Contraction of skeletal Muscle cells mechanism
INTRODUCTION
HISTORY
MECHANISM OF PROTEIN SYNTHESIS
TRANSCRIPTION
TRANSLATION
TRANSCRIPTION
INITIATION
ELONGATION
TERMINATION
TRANSLATION
AMINOACYLATION OF tRNA
INITIATION OF POLYPEPTIDE CHAIN
ELONGATION
TERMINATION
CONCLUSION
REFERENCES
Introduction.
History.
Central dogma.
Mechanism of protein synthesis.
Transcription.
Process of transcription
translation
Step of translation
Activation of amino acid.
Transfer of amino acid to tRNA.
Initiation of polypeptide chain
Elongation of polypeptide chain
Translocation
Termination of polypeptide chain
processing of released polypeptide chain
Main difference between protein synthesis in prokaryotes and eukryotes
Conclusion
Reference
Introduction
History
Geographical distribution
Genome Structure
Anatomy and Life Cycle
Significance of Arabidopsis in Plant Genetics
Conclusion
References.
INTRODUCTION
ABOUT DROSOPHILA
PHYSICAL APPEARANCE
CELL BIOLOGY OF DROSOPHILA DEVELOPMENT
LIFE CYCLE
THE DROSOPHILA GENOME
UNUSAL FEATURES OF DROSOPHILA
SEX DETERMINATION
GENETIC MARKERS
DEVELOPMENT IN DROSOPHILA
CLEAVAGE
THE ORIGINS OF ANTERIOR-POSTERIOR POLORITY {GENES}
CHROMOSOME ABERRATIONS
CONCLUSIONS
REFERENCES
Introduction And Classification
Anatomy Of Flower
Life Cycle Of Arabidopsis
Early Flower Development
Embryogenesis-
A. Formation Of Microspores
B. Formation Of Megaspores
Embryonic Development Starts By Establishing A Root-shoot Axis And Then Halts Inside The Seed
Arabidopsis Genome Is Rich In Developmental Control Genes.
Control Of Carpel & Fruit Development
Arabidopsis Thaliana A Model Plant
Conclusion
References
Introduction
About Drosophila
Genome of Drosophila
Life cycle
Differentiation
Development of Drosophila
* Embryonic development
* Dorsal -ventral and
* Anterior posterior development
* Body segmentation
* Homeotic gene
Conclusion
Reference
Introduction
The big question
Evolution of gene regulation
Gene regulation in eukaryotes
Points of control
Packing/unpacking DNA
Transcription
mRNA processing
mRNA transport
Translation
Protein processing
Protein degradation
Difference between eukaryotic &
prokaryotic gene expression
Conclusions
References
INTRODUCTION
DEFINATION
GAMETES
STRUCTURE OF GAMETES
SPERM
OVUM
RECOGNITION OF EGG AND SPERM
CAPACITATION
ACROSOME REACTION
SPECIES-SPECIFIC RECOGNITION
GAMETE BINDING AND RECOGNITION
GAMETE FUSION
PREVENTION OF POLYSPERMY
ACTIVATION OF GAMETE METABOLISM
FUSION OF THE GENETIC MATERIAL
SIGNIFICANCE OF FERTILIZATION
CONCLUSIONS
REFERENCES
Cellular response to environmental signals in plantKAUSHAL SAHU
INTRODUCTION
CELL SIGNALING:-
I) Unicellular and multicellular organism cell signaling.
II) Classification of intercellular communication.
RESPONSE TO STUMULI:-
(a) Plants
(b) Animals
SIGNAL TRANSDUCTION PATHWAY LINK INTERNAL AND ENVIRONMENTAL SIGNAL:
(a) Reception
(b) Signal transduction
(c) Response
HORMONE
CHEMICAL SIGNALS IN PLANTS
CONCLUSION
REFERENCE
Introduction
Tumours
Types of Tumours
Formation of Tumours
How cancer cell differ from normal cells
Classification of cancer
The causes of cancer
Viruses and Cancer
Cancer and Gene: A. Oncogene
B. Tumours suppressor gene
Detection and Diagnosis
Therapy of cancer
How can cancer are prevented
Conclusion
References
INTRODUCTION
HISTORY
GENES INVOLVED IN CANCER
ONCOGENES
TUMOUR SUPPRESSOR GENES
ONCOGENE
INTRODUCTION
TYPES
ACTIVATION OF PROTO ONCOGENES
FUNCTION
TUMOUR SUPPRESSOR GENES
INTRODUCTION
EXAMPLE
RB GENE
TP53 GENE
CONCLUSION
REFERENCES
INTRODUCTION
Definition
history
DIFFERENT PHASE
G0 PHASE
INTERPHASE
M PHASE
CHECKPOINT
HOW DOES IT WORK
Inhibitors
Mechanism of action
Function
CONCLUSION
references
CELL CYCLE
CELL CYCLE CHECK POINT
PHASES IN CELL CYCLE CHECK POINT
ROLE OF CYLINE AND CDKS
MUTURATIONAL PROMOTING FACTOR
FUNCTION OF MPR
CONCLUSION
REFRENCE
ion channel and carrier protein By KK Sahu SirKAUSHAL SAHU
INTRODUCTION - DEFINITION OF ION CANALS- HISTORY AND DIVERSITY OF ION CANALS- CARRIER PROTEIN-DEFINITION - CLASSES OF CARRIER PROTEIN - MECHANISM OF ION CANALS AND CARRIER PROTEIN - MEMBRANE TRANSPORT- BIOLOGICAL ROLE OF ION CANALS AND CARRIER PROTEIN - CONCLUSION - REFERENCE
Molecular event during Cell cycle By KK Sahu SirKAUSHAL SAHU
WHAT IS CELL?
WHAT IS CELL DIVISION OR CELL CYCLE?
WHY DO CELL DIVIDE?
HISTORY
CELL CYCLE
INTERPHASE
M-PHASE
MOLECULAR EVENT DURING CELL CYCLE AND CELL REGULATION
TYPES OF CELL DIVISION
IMPORTANCE OF CELL DIVISION
ABNORMALTIES OF CELL CYCLE
REFRENCES
WHAT IS CELL?
WHAT IS CELL DIVISION OR CELL CYCLE?
WHY DO CELL DIVIDE?
HISTORY
CELL CYCLE
INTERPHASE
M-PHASE
MOLECULAR EVENT DURING CELL CYCLE AND CELL REGULATION
TYPES OF CELL DIVISION
IMPORTANCE OF CELL DIVISION
ABNORMALTIES OF CELL CYCLE
REFRENCES
Abnormalities 0f mitotis By KK Sahu SirKAUSHAL SAHU
INTRODUCTION
WHAT IS MITOSIS
PHASES OF CELL CYCLE AND MITOSIS
SOURCE & REASON OF ABNORMAL MITOSIS
EFFECTS OF ABNORMAL MITOSIS
ABNORMALITIES OF MITOSIS IN PLANTS
ABNORMALITIES OF MITOSIS IN ANIMALS & HUMAN BEINGS
FACTORS RESPONSIBLE FOR MITOTIC ABNORMALITY
ADVANTAGES & DISADVANTAGES OF ABNORMAL MITOSIS
CONCLUSION
REFERENCE
Transport of small molecule across cell membrane By KK Sahu SirKAUSHAL SAHU
INTRODUCTION OF PLASMA MEMBRANE
MODEL OF PLASMA MEMBRANE
TRANSPORT OF SMALL MOLECULE
PASSIVE TRANSPORT
TYPE ( DIFFUSION, FACILITATED)
MECHANISM
REFRENCES
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
1. •By
•KAUSHAL KUMAR SAHU
•Assistant Professor (Ad Hoc)
•Department of Biotechnology
•Govt. Digvijay Autonomous P. G. College
•Raj-Nandgaon ( C. G. )
•
3. “ It is the process by which an extra cellular
signaling molecule activates a membrane
receptor, which in turn alters intercellular
molecules creating a response.” The stimulus
received at the cell surface is entirely
different from the signal released to the cell
interior, the signal received is amplified.
4. .
• In 1970 Martin Rod bell Firstly examined Signal
Transduction, through effect of glucagons on a rat’s liver
cell.
glucagons
+ bind
Guano sine triphosphate disassociated glucagons
↓
stimulates G- protein
↓
strongly influences the cell metabolism
5. BASIC ELEMENTS IN SIGNAL TRANSDUCTION
• Ligands:- also known as signals or first
messenger.
• Receptor:- transmembrane protein that
binds to the ligand
• Second messenger
6. SIGNALING MOLECULES
• There are two kinds of signaling molecules.
1. Some signaling molecules cross the plasma membrane and bind
to the receptors on the target cell.eg. Steroid hormones.
2. Another signaling molecules can’t enter the plasma membrane
and thus binds to the receptors on the plasma membrane.
e.g..Gprotein
E.g. of signaling molecule
1. STEROID HORMONE
2. NITRIC OXIDE
3. CARBON MONOXIDE
4. NEUROTRANSMITTER
5. PEPTIDE HORMONE
8. G-PROTEIN LINKED RECEPTOR
• This protein was discovered and characterized by Red bell and
his colleagues at the National Institute of health in the early
1970’s.
• G-protein coupled receptors are a family of integral membrane
proteins
• It is also known as seven transmembrane domain receptors as it
possess seven membrane spanning domains.
• It is linked to a guanine nucleotide binding protein.
• Two pathways involve G- protein coupled receptor:
• cAMP pathway
• Phosphatidylinositol pathway
• The G-protein linked receptors are coupled to their target
enzymes in the plasma membrane through trimeric GTP binding
proteins, called G proteins
9. • G
protein
undergoe
s
change
•
GProtein
binds to
receptor
• GTP
replaces
GDP
• Disassoc
iation of
G
protein
• ßϒ +ἀ
+GTP
• ἀ gives
the msg
to target
• GTP
hydrolysi
s
• G
protein
linked
receptor
• Ligand
binds to
receptor
• GProtein
original
form
10. ION LINKED CHANNEL RECEPTORS
• Hydrophobic molecules- Rapidly diffuse
• Uncharged small polar molecules- Rapidly diffuse
• Uncharged large polar molecules- moves through pores using carrier
protein
• Charged molecules-ion channels or active transport
E.g.
11. NUCLEAR RECEPTOR
• STEROID RECEPTOR
• It is located primarily within the cytosol
• In the absence of ligands they are associated with chaperons.
steroid hormone
↓
chaperone activates the receptor
↓
protein folds
↓
signal enters into the nucleus
12. SECOND MESSENGER
• Link between first messenger and target cell.
• They are generated when first messenger binds to the receptor.
• They are water soluble and relatively smaller in size.
• E.g. Calcium ion, Nitric oxide
CALCIUM ION AS SECOND MESSENGER
• It is present in limited amount inside the cell.
• Present in endoplasmic reticulum in muscles and nervous tissue
• It is inactive when present in its original site.
• It is active when released in the cytosol.
13. ACTIVATION OF Ca2+
Calcium (Inactive state)
↓
First messenger comes and binds to receptor
↓
This interaction induces a conformational change in proteins
↓
Protein specific to calcium channels open the channels for Ca
↓
Calcium ions exit from intracellular storage sites into the cytoplasm
↓
Calcium (active state)
↓
Carries message to the target site
↓
Triggers target site for response
FUNCTION: Muscle contraction, vision in retina cells,proliferation of cells
14. • NITRIC OXIDE AS SECOND MESSENGER
It acts as a second messenger in many processes such as
• Relaxation of blood vessels
• Regulation of neurotransmitters
• Cellular immune response
• Production and maintenance of penile erections
• Activation of apoptosis
• It also plays an important role in generation of cGMP
In high concentration NO is Toxic, It may result in stroke
21. SOME EXAMPLES OF PATHWAY SIGNALING
• cAMP pathway- It contains five main characteristics:
• Stimulative hormone receptor (Rs)
Inhibitory hormone receptor (Ri)
• Stimulative regulative G-protein (Gs)- binds with
Stimulative receptor
Inhibitory regulative G-protein (Gi) - binds with Inhibitory
receptor
• Adenylyl cyclase- 12- transmembrane glucoprotein that
catalyses ATP to form cAMP with the help of Ca.
• Protein kinase A
• cAMP phosphodiesterase
22.
23. RAS MEDIATED SIGNAL TRANSDUCTION PATHWI
It contains four main characteristics:
•Receptor Tyrosine Kinase
•Growth factor
•Ras proteins
•MAP- kinase
•They are products of proto oncogenes c-ras.
•They are active only when bound to GTP and inactive when bounded with GDP.
•Two classes of signalling proteins that regulate Ras activity include the following:
•GTPase activating proteins (GAPs) - it increases the rate of hydrolysis of bound GTP by Ras
resulting in inactivated Ras.
•Guanine nucleotide releasing proteins (GNRPs) - it promotes the release of GDP and uptake of
GTP resulting in activated Ras.
•Thus Tyrosine kinase activates Ras proteins either by inhibiting GAP or activating
•GNRP
•Ras proteins when active initiate a cascade of phosphorylation which leads to MAP- kinase
(mitogen activated protein) which finally relays signals to nucleus.
24.
25. • Every single way our body reacts depend on the way
our receptors catches signals and transducts them to
the target cells.
• Our life susceptibility depends on signal transduction
• Errors in cellular information processing are
responsible for many diseases such as cancer, heart
problems etc.
• Full study of signal transduction helps in creating
synthetic drugs,
• And also artificial tissue.
26. CONCLUSION
• Cell signalling is a most important function in
all animals and plant cells
• Numbers of research being carried out
indicate that all organisms share certain basic
signalling mechanism but certain pathways are
unique to each major kingdom.
• The scientist world has recognize the
significance of signal transduction mainly in
drug production but still many of its areas are
left to be explored.
27. REFERENCE
• THE CELL- A Molecular Approach- By M.Cooper &
Geoffery (2006)
• Text Book of cell Biology- By Karp (2007)
• Cell And Molecular Biology- By P.K.Gupta (2008)
• Gene viii- By Lewin & Benjamin(2006)
• Genetics- By B.D. Singh