Scientists discover a new mechanism of photosynthesis for the plant hormone auxin. Read here the types and characteristics of the auxin hormone. Liquid-filled microchannels and Flipped-over microscopes.
|The mechanism of photosynthesis for the plant-Auxin-hormone-function|
Auxin Hormone Function-The Mechanism of Plant Hormone Distribution
Plant hormones are those organic substances produced by living organisms at a very low concentration in certain places in the organism so they can be taken to different places of the body for use on the face.
Plant hormones or growth regulators in plants are organic compounds produced in metastatic regions. Plants are released from them to be induced in other areas of the plant.
Types of plant hormones
Plant hormones can be divided into two main types: Growth hormones and inhibitory hormones
Growth hormones, which include:
Auxins: One of the growth hormones that affect the growth of plants, and is found in the tops of plants, leaves, roots, and new buds, and works to elongate the cells of the roots and leg and leaves and works on the division of cells.
Jibrilins: Hormones are found in all parts of plants in varying amounts and are found in seeds that are not fully grown in high quantities.
Cetenoids: These are different forms of adenine compounds and regulate the growth of lateral branches in plants.
Inhibitory hormones that include:
Cycocel: A growth inhibitor, an antimicrobial agent. This compound has a great ability to transport all parts of plants.
Abyssic acid, or acid, is one of the hormones responsible for scattering plant leaves and fruits and separating them from trees. It also plays the role of the hormone responsible for transmitting sensory responses in plants.
Ethylene: It is one of the plant hormones that works to accelerate the maturation of fruits in plants and accelerate the fall of leaves.
Functions of plant hormones
Plant hormones have many important functions in plants. The most important of these functions are:
- Help in rooting plants.
- Accelerate the process of forming or delaying fruits according to the type of plant hormone.
- Modification or modification and modification of plant species.
- Control the size of plants, and different organs in the plant.
- Increasing the acceleration of vegetative growth.
- Work to increase the resistance of plants to different environmental conditions and the ability to bear.
- Increase plant resistance to harmful pests and various diseases.
- Control the growth and color of fruits and leaves, and accelerate the process of dropping or remaining from the plant.
|The mechanism of photosynthesis for the plant- Auxin-hormone-function|
It should be noted that plant hormone often interferes with their functions in many plants, we find that different hormones do more than one purpose at the same time, and also change the characteristics of each other when they interfere with the plant, and this explains the emergence of new mutations in plants or races Specific show for the first time.
Characteristics of the auxin hormone
Auxin is a plant hormone with certain characteristics such as morphogen. It has a cardinal role in the coordination of many growths and behavioral processes in the plant’s life cycle.
It is essential for the development of plants as it controls a wide range of processes from shaping the embryo in the seed to the branching of the growing plant.
Auxin and its role in plant growth was first described by the Dutch scientist Frits Wrmolt went , and Kenneth V. thimann was the first scientist who isolated one of the phytohormones, determined its molecular level and chemical structure and defined it as “, all auxins are compounds with an aromatic ring and a carboxylic acid group”.
The most important member of the auxin family is an indole-3-acetic acid which generates the majority of auxin effects in intact plants and is the most potent native auxin.
And as native auxin, its stability is controlled in many ways in plants, from synthesis, through possible conjugation to degradation of its molecules, always according to the requirements of the situation.
In the past, it was believed that auxin's main signaling mechanism operated in the cell nucleus and acted only by regulating gene transcription.
Recently, scientists at the Institute of Science and Technology Austria have demonstrated that another mechanism exists and that cells in the roots must be able to respond to auxin immediately.
This mechanism enables a rapid adaptation of the root development direction.
The pattern of auxin distribution
The pattern of auxin distribution within the plant is a key factor for plant growth, its reaction to its environment, and specifically for the development of plant organs, it is achieved through the so-called polar auxin transport through the very complex and streamlined active transport of auxin molecules from cell to cell in the entire body of the plant.
Thus, a plant can react to external conditions and adjust them without the need for the nervous system. its mechanism can be described as ‘ the seed of a plant germinates and its root needs to quickly establish the direction of gravity and bend to grow deeper inside the soil, where it can anchor itself, and find nutrients and water.
While being inhibited on the other, cell growth is allowed to continue on one side of the root.
This barrier hormone was triggered by auxin and was known to be very quick, but accurate reaction time was difficult to measure.
Using an innovative setup, researchers can now measure the time's need to react to changes in auxin concentration. They concluded that the extremely rapid adaption of growth rate was far too fast to be explained by the gene transcription mechanism, and therefore must involve a correspondingly rapid perception mechanism.
Auxin usually works in concert with or against other hormones of other plants.
Scientists discover a new mechanism of photosynthesis for the plant hormone auxin
|The mechanism of photosynthesis for the plant-Auxin-hormone-function|
The new branch in an old pathway
Jiří Friml, Professor at the Institute of Science and Technology Austria explained “new mechanism is not entirely unknown. Components of the well-studied pathway, the TIR1 receptor, are needed for the newly discovered mechanism.
With our experimental setup, we proved that the signaling is indeed non-transcriptional, but we have seen that components of the original transcriptional pathway are needed, this means that we are not looking at the completely new path but rather in a new branch of the canonical passage.
Liquid-filled microchannels and Flipped-over microscopes
Matyáš Fendrych, former postdoc in Friml's group and now assistant professor at the Charles University in Prague explained "Generally, people will apply auxin and then mount the sample on the microscope, but with this method, they will lose valuable seconds or even minutes - and in fact, those few minutes are the ones that were necessary for the study.
The solution retraced by the team was to raise the roots in the desired fluid-filled microscopic channels."It allowed us to change the auxin concentration and immediately measure the response to the root.
With a microscope that was flipped on its side -- a method that was developed previously by the same research group and the team was able to observe the roots grow in their natural orientation. But in order to measure reaction time, further development of technology is needed: they should be able to change the solution growing in the roots immediately.
But this research led to the production of a breathtaking video of growing roots that won last year's "Nikon Small World in Motion Competition”.
Journal Reference: Nature
Story Source: ScienceDaily25 June 2018.