Macros Lab

5. The cell body of the neuron, responsible for maintaining the life of the cell and containing the mitochondria is the soma.

The genes which encode for the mitochondria’s component proteins are in 2 separate genetic systems in 2 different locations. One of which is the cell nucleus, but the other is inside the organelle itself. There are relatively few genes inside the

Mitochondria, dubbed the ‘powerhouse of the cell’, are a type of organelle present in most human cells. Their primary function is to generate Adenosine Triphosphate (ATP), the cell’s principal source of chemical energy. Unlike most other organelles, mitochondria store their own set of genetic material, distinct from the DNA situated in a cell’s nucleus. Although this ‘mitochondrial genome’ represents only 0.1% of a cell’s genetic information, it often plays a significant role in development.

There are hundreds of neurodegenerative diseases (NDD) and the etiology for most of the random conditions remain a universal mystery (Nieoullon 2011). A deterioration of specific functions of the neuron cells of the central nervous system is the most common characteristic of NDD. Neurons are responsible for transmitting essential information to other nerve, muscle and glandular cells (Przedborksi, Jackson-Lewis 2003). Emerging research has recently identified mitochondrial dysfunction as a recurrent elemental link in numerous neurodegenerative disorders (Ghano,

Another process for targeting has become specific and includes targeting mitochondria of the cell to take the photodamage. 5 One study by Henderson6 shows that there is an active relationship between structure and activity of these

This research is significant because a better understanding of the neuronal effects of the disease will greatly facilitate efforts in treating GD, benefiting patients who suffer from the disease. Furthermore, by studying different pharmacological agents, we can attempt to find potential treatments or cures for the disease. Additionally, it has been shown that carriers of GD are at an increased risk of developing Parkinson’s disease, and so this research may also bring about a new understanding of Parkinson’s. The significance of the research was just one of the many factors that drew my interest. I was also drawn by the fact that this research involves the Wnt pathway, which I was somewhat familiar with due to my previous work in Dr. Yang’s laboratory. Another reason why I chose to join Dr. Feldman’s group was due to my interest in learning about stem cells. I was curious as to how stem cell research is carried out, so the fact that the group used induced pluripotent stem cells to conduct their research was very appealing. Lastly, I was interested in exploring and witnessing translational research in practice, which I was able to do in Dr. Feldman’s Lab, although this was limited by the short duration of the internship. Still, we were able to identify a possible method to reverse the neuronal effects of GD, and this

In the last years, mitochondrial dysfunction and subsequent energy penalty have been hypothesized to drive axonal

On the other hand fusion is associated with optimization of mitochondrial functions and is regulated by three major proteins i.e. mitofusin 1(Mfn1), mitofusin 2(Mfn2) and optic atrophy protein1(OPA1). Mfn1 and Mfn2 are mitochondrial transmembrane proteins localized to the outer membrane. During mitochondrial fusion Mfn 1 and Mfn 2 form hetero-oligomeric and homo-oligomeric complexes that join outer membranes of mitochondria. Inner mitochondrial membrane fusion is mediated by OPA1 and Mfn 1. Mounting evidence implicate that the expression level of mitochondrial dynamin proteins i.e. Drp 1, Opa 1, Mfn-1, Mfn-2 is decreased in the pathogenesis of complex neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and Huntington's disease while Fis-1 levels are increased which results in abnormal mitochondrial distribution in neurons of AD patients as compared to age-matched controls. These changes in mitochondrial dynamics significantly impact almost all aspects of mitochondrial functions including energy metabolism, calcium buffering, reactive oxygen species(ROS) generation and apoptosis

The mitochondria, also referred to as the powerhouse of the cell, is found in most eukaryotic cells, including both plant and animal cells. It has a shape of an oval, and is held together by a double membrane. The outer membrane is comparable to skin as it covers the mitochondria and protects it. The inner membrane is folded

This would mean that the cells that require a lot of energy however would not get it, which would result in tiredness, fatigue and the body not functioning efficiently. Also, diseases that affect the mitochondria can affect the functions and cause death of many numbers of cells which can damage the vital internal organs and the body as entirety. We would not live if all the mitochondria in the liver cell were to be destroyed. As mitochondrion is known as the power house of energy, it provides energy to it. The electron micrograph shows the rough endoplasmic reticulum and mitochondria of a liver cell. It also shows there are a lot of mitochondria in the liver cell because the body arranged this specific organ to do perform a variety functions. The reason why liver cells have a high number of mitochondria is because it has to get a lot of energy at one time in order to be more efficient. The liver itself is the largest internal organ in the whole body and hence requiring a large amount of mitochondria to perform at a suitable, appropriate and efficient level. Being the largest organ, it is necessary for it to have a significant amount of mitochondria as it needs a tremendous amount of energy or it shall stop functioning and problems will arise like liver

The hub of energy metabolism, the mitochondrion, is found in virtually all eukaryotic cells, with the exception being erythrocytes. The mitochondrion generates cellular energy in the form of adenosine triphosphate (ATP), mostly by means of the oxidative phosphorylation (OXPHOS) system that is located in the inner mitochondrial membrane. The respiratory chain (CI-CIV) and ATP synthase (CV) is collectively known as the OXPHOS system, encoded by both nuclear DNA (nDNA) and mitochondrial DNA (mtDNA). The number of mitochondria per cell, ranging from hundreds to thousands, is controlled by the energy requirements of specific tissues with the greatest abundance of mitochondria found in metabolic active tissue (Pieczenik and Neustadt, 2007). Mitochondrial disease is caused when there is a defect in any of the numerous mitochondrial pathways, due to spontaneous or inherited mutations. Respiratory chain deficiencies (RCDs) are the largest subgroup of mitochondrial disease and occur when one of the four respiratory chain complexes become impaired. RCDs are considered to be one of the most common

Presbycusis or Age-related hearing impairment is the most frequent sensory disorder in the adults. It affects more than half of all adults by age seventy-five years. Presbycusis is an irreversible symmetrical progressive loss of hearing sensitivity during the lifespan. It has an insidious onset without clinical manifestation so detected by the routine diagnostic test after losing or damaging to inner ear cells and neurons. Presbycusis counted as an untreatable disorder since these inner ear structures lose the ability of regeneration. Mitochondria by production reactive oxygen species or inducing apoptotic genes is one of most prominent intracellular organelles that contribute in presbycusis progression. The present study focused on mitochondrial

Each cell contains hundreds to thousands of mitochondria (1), which are located in the fluid that surrounds the nucleus called cytoplasm. Mitochondria are organelles within cells that convert the energy from food into a form that cells can use. Mitochondria produce energy through a process called oxidative phosphorylation which is the final stage of cellular respiration. During oxidative phosphorylation, an electron transport chain works in conjunction with chemiosmosis to create energy molecules named adenosine triphosphate (ATP) using oxygen and simple sugars. In the electron transport chain, an electrochemical gradient is formed by the chemical gradient from the inside to the outside of a mitochondrion counteracting with the electrical gradient from the outside to the inside of the mitochondrion. During chemiosmosis, the energy stored in the gradient is used to make ATP.

This is further supported by the fact that there are comparable numbers of mitochondria distributed at different distances from the soma in WT and RTT neurons. Therefore, WT and RTT mitochondria do reach the synapse, but do so at different velocities. As it takes longer for the RTT mitochondria to reach the synapses, they would have synthesized more ATP before they reached the synapse. This may help explain the cause of synaptic dysfunction in RTT neurons, as the increased demand for ATP to facilitate trafficking will reduce their efficiency in the synapse. Further studies to measure ATP levels at the synapse will need to be conducted to confirm this statement. However, results showed that 5µM SW-100 does not significantly affect mitochondrial velocity in neurons of both genotypes, which indicates that either the drug has no effect on mitochondrial trafficking or higher concentrations are needed.

The most prominent cytoplasmic alterations were to the mitochondria. Paracrystalline inclusions were found in many of the mitochondria. These inclusions, are very rare or are non existent in the interfibrillar mitochondria. Each crystalloid is enclosed by a single membrane and at low magnification appeared to be parallel linear densities measuring .34nmin thickness. Higher magnification revealed that the laminae of the crystalloids consisted of linearly arranged dots that were ~34nm in diameter. Some mitochondria, both SSM and IFM, lacked crystalloid inclusions and had few cristae, these particular mitochondria were confined to the organelle periphery where they paralleled the limiting membranes, this left a large area absent of any membranes in the inner compartment. These zones had a variety of different appearances, some mitochondria where completely electron-lucent, others possessed farinaceous material that varied in density, which depended on concentration and packing of electron-dense particles.