molecular and genetic analysis of floral induction is an integrated approach, taking into consideration various genes involved in the four major pathways of flowering process
flowering is perhaps the most important physiological phenomenon in the life-cycle of higher plants. it is a resultant of a range of internal and external factors, that leads to the activity of a plethora of genes, that leads to the development of flowers
flowering is perhaps the most important physiological phenomenon in the life-cycle of higher plants. it is a resultant of a range of internal and external factors, that leads to the activity of a plethora of genes, that leads to the development of flowers
intro-hostory and discovery-characteristics of phytochrome-chemical nature of phytochrome-mode of action-mechanism-phytochrome mediated physiological responses-phytochrome is a pigment system:some evidences-role of phytochrome
Everything about photoperiodism from scratch to smart, from the oldest models to the latest models as well as proposed one, exclusive and elusive illustrations and models for proper understanding
photoperiodism its discovery,significance,classifications,mechanism,critical day length,quality of light, night break phenomenon,phytochrome.florigen,floering genes, circadian rhythm
By -
Avinash Darsimbe
Assistant Professor
Department of Botany
Shri Shivaji Science College, Amravati
Physiology of Senescence and Abscission
B.Sc. III (Sem - V)
BOTANY : PLANT PHYSIOLOGY AND ECOLOGY
Sant Gadge Baba Amravati University,Amravati
What is the model for floral induction by day-lengthSolutionB.pdfneerajsachdeva33
What is the model for floral induction by day-length?
Solution
Basically there are Long day plants and Short day plants. In both of these types the alternate day
and night duration is important for flowering. A research on Effect of photoperiodism on
flowering in Arabidopsis, (a long day plant) has revealed the role of many genes involved in the
process. The Flowering is promoted by a promoter gene Constans (CO), which in turn regulates
the level of FT mRNA acumulation.
Photoreceptor(FKF1) ---> Flowering promoter(CO) -----> Expression of florigen
In short day plants flowering can be induced by AP1 gene only. In rice the flowering depends on
two genes: One promoter(Ehd1) and other repressor(Ghd7). Promoter expresses florigen.
Floral induction starts when there occurs a transition from vegetative to reproductive phase and a
signal is passed when there is formation of floral meristem from stem. It starts the functioning of
many genes who carry out this process further. At an early stage CO gene is induced. Duration of
day light affects CO locus. CO in turn initiates production of FT protein responsible for
flowering induction. Longer day length regulates increased CO synthesis and also regulates
genes like AG and LFY which express A, B, C genes FT protein is linked to FD protein in shoot
apex which induces flowering..
intro-hostory and discovery-characteristics of phytochrome-chemical nature of phytochrome-mode of action-mechanism-phytochrome mediated physiological responses-phytochrome is a pigment system:some evidences-role of phytochrome
Everything about photoperiodism from scratch to smart, from the oldest models to the latest models as well as proposed one, exclusive and elusive illustrations and models for proper understanding
photoperiodism its discovery,significance,classifications,mechanism,critical day length,quality of light, night break phenomenon,phytochrome.florigen,floering genes, circadian rhythm
By -
Avinash Darsimbe
Assistant Professor
Department of Botany
Shri Shivaji Science College, Amravati
Physiology of Senescence and Abscission
B.Sc. III (Sem - V)
BOTANY : PLANT PHYSIOLOGY AND ECOLOGY
Sant Gadge Baba Amravati University,Amravati
What is the model for floral induction by day-lengthSolutionB.pdfneerajsachdeva33
What is the model for floral induction by day-length?
Solution
Basically there are Long day plants and Short day plants. In both of these types the alternate day
and night duration is important for flowering. A research on Effect of photoperiodism on
flowering in Arabidopsis, (a long day plant) has revealed the role of many genes involved in the
process. The Flowering is promoted by a promoter gene Constans (CO), which in turn regulates
the level of FT mRNA acumulation.
Photoreceptor(FKF1) ---> Flowering promoter(CO) -----> Expression of florigen
In short day plants flowering can be induced by AP1 gene only. In rice the flowering depends on
two genes: One promoter(Ehd1) and other repressor(Ghd7). Promoter expresses florigen.
Floral induction starts when there occurs a transition from vegetative to reproductive phase and a
signal is passed when there is formation of floral meristem from stem. It starts the functioning of
many genes who carry out this process further. At an early stage CO gene is induced. Duration of
day light affects CO locus. CO in turn initiates production of FT protein responsible for
flowering induction. Longer day length regulates increased CO synthesis and also regulates
genes like AG and LFY which express A, B, C genes FT protein is linked to FD protein in shoot
apex which induces flowering..
Pharmacology 1st
B pharmacy 4th sem Sy B Pharmacy
Transmembrane Enzyme Linked receptors Transmembrane JAK-STAT binding receptor and receptors that regulate transcription factors
Everything about photoperiodism from scratch to smart, from the oldest models to the latest models as well as proposed one, exclusive and elusive illustrations and models for proper understanding
Signal transduction Calcium Signaling vibhakhanna1
A wide range of Ca2+ signaling pathways deliver the spatial and temporal Ca2+ signals necessary to control the specific functions of different cell types, via various effector proteins and protein kinases
the ubiquitous calcium binding protein present in both animals and plants and plays a crucial role in signal transduction via calcium ions as second messengers
An introduction to the concept of Signal transduction mechanism prevalent in lower organisms, particularly bacteria. Also forms a part in many eukaryotic systems of signal transduction, particularly in the plant world.
Biological assays are methods for the estimation of nature, constitution or potency of a material by means of the reaction that follows its application to living matter
the flowering process is the combined effect of environmental factors like light and temperature. vernalisation is the epigenetic memory that leads to genetic regulation of the process
Gene pool concept for breeding purposevibhakhanna1
The Harlan and deWet gene pool concept is one of the basic concept to develop an understanding of alien gene transfer and its use in evolution of domesticated crops.
after floral induction, the inflorescence meristem eventually forms the floral meristem. the process is controlled by an array of homeotic genes. this also involves microRNAs for their regulation
despite of the enormous genomic diversity, the phage genome mapping is being done using a plethora of techniques,which includes both genetic mapping and physical mapping
bacteriophages require bacterial host to complete its life-cycle, wherein site-specific genetic recombination occurs. furthermore, homologous recombination also occur in phages in case of multiple infection of the host cell.
transduction is a mode of horizontal gene transfer in which the recipient does not come in contact with the donor bacterial cell, it is mediated by temperate phages.
transformation in bacteria is a classical example of horizontal gene transfer which leads to enhanced survivability and also introduction of variations that may lead to evolution
the horizontal gene transfer in bacteria is not only important for survival but has its evolutionary significance too. this presentation is a prelude to the three classical types of HGT in bacteria
Assimilation of ammonium ions is the ultimate aim of nitrogen metabolism in plants. this is the source of nitrogen for various organic compounds of structural and functional importance for the living world
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
How to Create Map Views in the Odoo 17 ERPCeline George
The map views are useful for providing a geographical representation of data. They allow users to visualize and analyze the data in a more intuitive manner.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
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This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
2. PLANT PHYSIOLOGY
THE FLOWERING PROCESS
PRESENTATION 4:
Floral Induction:
‘Genetic And Molecular Analysis’.
(i.e., the mechanisms by which genes control
development, growth and physiology.)
3. FLOWERING PROCESS
• There are a number of different developmental phases through
which a plant progresses during its life cycle.
• Flowering is an essential part of the reproductive process in
angiosperms, and the flowering process involves two
developmental phase transitions:
– the first of these is the transition from the immature juvenile
vegetative state (where the plant is unable to flower) to the mature
adult vegetative state (where the plant is capable of flowering).
– The second developmental transition occurs at floral induction when
the plant switches from vegetative growth to reproductive growth and
starts to produce flowers.
• The timing of this transition is tightly controlled by a complex gene
regulatory network.
• The plant detects environmental cues such as light quality and
duration, and temperature and integrates this information with that
from endogenous physiological processes such as its circadian clock,
phytohormone and carbohydrate levels, and vernalization state to
regulate its flowering time.
4. FLORAL INDUCTION
• The two developmental phase transitions that leads to the production of
flowers.
– The first is the juvenile–adult phase transition after which the plant is
competent to be induced to flower,
– the second is the vegetative–reproductive phase transition which occurs once
a plant has been induced to flower
• This is followed by the production of floral organs (development of
flower).
5. Regulation Of Floral Induction
• The main pathways controlling flowering in response to environmental signals
are the photoperiod (day length), ambient temperature (surrounding
temperature) and vernalization (prolonged cold exposure) pathways.
• Other endogenous factors such as phytohormones and carbohydrate status
also regulate flowering through the autonomous, gibberellic acid (GA),
nutrient‐responsive and ageing pathways.
• All these different regulatory pathways converge on a set of floral pathway
integrator genes, namely FLOWERING LOCUS T (FT) and its paralogue* TWIN
SISTER OF FT (TSF), as well as SUPPRESSOR OF CONSTANS 1 (SOC1)
and AGAMOUS‐LIKE 24 (AGL24).
• These act to control the expression of a small set of meristem identity genes at
the shoot apical and lateral meristems including LEAFY (LFY), APETALA 1 (AP1)
and FRUITFUL (FUL).
• Once the expression of these genes reaches a certain level they induce the
expression of floral organ identity genes and flowers are produced
{* a pair of genes that derives from the same ancestral gene and now reside at
different locations within the same genome.}
7. MERISTEM IDENTITY GENES
I: Shoot Meristem Identity Genes
• The meristem identity genes can be divided into
two subclasses:
I. the shoot meristem identity genes and
II. the floral meristem identity genes.
• Shoot meristem identity genes such as TERMINAL
FLOWER1 (TFL1) specify the inflorescence shoot
apical meristem as indeterminate and non-floral.
• Ectopic expression i.e. abnormal gene expression
of TFL1 converts the normally floral lateral
meristems, that arise on the flanks of the shoot
apical meristem, into shoots.
8. II: The Floral Meristem Identity Genes
• The floral meristem identity genes such as LFY and APETALA1
(AP1), specify lateral meristems in Arabidopsis to develop into
flowers rather than leaves or shoots.
• Although AP1 and LFY are the major floral meristem identity
genes, other genes such as CAULIFLOWER, FRUITFULL, and AP2
play secondary roles in specifying floral meristem identity.
• Both LFY and AP1 encode sequence-specific DNA binding
transcription factors.
• AP1 is a member of the MADS family, whereas LFY encodes a
plant-specific protein.
• Although transcription of AP1 and LFY in lateral meristems is
sufficient to specify them as floral meristems, there are other
factors, independent of LFY and AP1, that determine the
competence of the plant to flower.
9. Integration Of Flowering Signals By
FLC, SOC1, FT And LFY
• The activation of LFY and AP1 leads to the
development of flowers.
• LFY and AP1 respond, either directly or indirectly,
to outputs of flowering time pathways.
• Some of the outputs of the flowering time
pathways are integrated by LFY, whereas others
are integrated upstream or in parallel to LFY by
FLOWERING LOCUS C (FLC), SUPPRESSOR OF
OVEREXPRESSION OF CONSTANS (SOC1), and
FLOWERING LOCUS T (FT).
10. Integration Of Flowering Signals By FLC
Via SOC1 &LFY
• Repressive signals from the
autonomous and vernalization
pathways are integrated by the floral
repressor FLC [FLOWERING LOCUS C].
• FLC also integrates positive
regulatory signals from the genes
FRIGIDA (FRI) and PHOTOPERIOD
INDEPENDENT EARLY FLOWERING1
(PIE1).
• FLC encodes a MADS transcription
factor. There is a strong correlation
between the levels of FLC
RNA/protein and the timing of
flowering:
– high levels of FLC correlate with late
flowering, and
– low levels of FLC correlate with early
flowering.
11. Integration Of Flowering Signals By FLC
Via SOC1 &LFY
• The autonomous pathway genes function to
downregulate the levels of FLC RNA/protein.
• The best described molecular mechanism involves the
autonomous pathway gene FLOWERING LOCUS D
(FLD), which encodes a protein that is a component of
the histone deacetylase complex.
• Histone deacetylases function as transcriptional
repressors by deacetylating histones, resulting in a
transcriptionally inactive chromatin state.
• The autonomous pathway genes FY and FCA function
to regulate the processing of FLC RNA.
12. Integration Of Flowering Signals By FLC
Via SOC1 &LFY
• Vernalization also results in a reduction in FLC RNA/protein levels.
• Vernalization controls FLC epigenetically {i.e. changes in gene
function that do not involve changes in DNA sequence}, either by
altering the methylation state of FLC or by controlling chromatin
structure.
• VERNALIZATION2 (VRN2), gene is necessary for the maintenance of
vernalization (i.e., stable downregulation of FLC levels after
vernalization).
• VRN2 encodes a Polycomb group protein.
• Polycomb proteins are important for stable transcriptional
repression and are postulated to function by altering chromatin
structure.
• The FLC activator PIE1 encodes a protein with similarity to ATP-
dependent chromatin remodeling proteins; in other systems, PIE1-
like proteins function to put chromatin in a transcriptionally active
state.
• In turn, FLC functions to repress the floral activator SOC1.
13. Integration Of The FLC And CO Signals
• SOC1, like FLC, encodes a MADS
transcription factor.
• SOC1 is activated by the long-day
promotion pathway via CO as well
as by the GA pathway.
• Integration of the FLC and CO
signals is mediated by discrete
elements in the SOC1 promoter.
• A consensus MADS binding
sequence in the SOC1 promoter
can be bound by FLC.
• Although a CO-responsive region
of the SOC1 promoter also was
defined, the activation is indirect
or probably CO requires a
cofactor for sequence-specific
DNA binding.
14. Integration Of The FLC And CO Signals
• The removal of the FLC repression of SOC1 is not sufficient to result
in high SOC1 transcript levels; upregulation of SOC1 also requires
positive activation by either the GA or the long-day promotion
pathway.
• In short days, the GA pathway is the only pathway that can activate
SOC1.
• Like SOC1, LFY is a key integrator of output signals from the long-
day promotion and GA pathways.
• Separate LFY promoter elements have been shown to mediate the
response to long days (photoperiod promotion) and short days (GA
promotion).
• The GA effects on the LFY promoter require an 8-bp binding site
that is a perfect match for the sequence recognized by a MYB
transcription factor which is upregulated by GA.
• The photoperiod promotion effects on LFY may be mediated by
SOC1 or by a second MADS gene, AGAMOUS-LIKE24 (AGL24).
15. FT: The Third Integrator Of Floral Induction
Pathways
• The third major integrator of flowering time
pathways is FT.
• Primarily long-day photoperiod promotion activates
FT; this is mediated via CO.
• FT also receives inputs from FLC.
• The long-day promotion pathway functions by
activating LFY and AP1 via separate branches of the
photoperiod pathway.
• Downstream of CO, the pathway splits; one branch
functions via SOC1 and LFY, the other via FT.
• CO is the last identified component of the long-day
promotion pathway that is upstream of both LFY and
FT.
16. FT: The Third Integrator Of Floral
Induction Pathways
• The branch of the pathway that acts via FT appears to
promote flowering by ultimately activating AP1 rather than
LFY.
• AP1 and LFY are necessary to specify floral meristem
identity, AP1 functions largely downstream of LFY.
• LFY is necessary for the proper expression of floral organ
identity genes, and this activity of LFY is independent of
AP1.
• The activation of AP1 by LFY is direct. The AP1 promoter
contains a sequence that can be bound by the LFY protein.
• There is a mutually repressive relationship between the
shoot identity gene TFL1 and the meristem identity genes
LFY and AP1, and the repression is mediated at the
transcriptional level.