Tau proteinThe tau proteins (abbreviated from tubulin associated unit) are a group of six highly soluble protein isoforms produced by alternative splicing from the gene MAPT (microtubule-associated protein tau). They have roles primarily in maintaining the stability of microtubules in axons and are abundant in the neurons of the central nervous system (CNS), where the cerebral cortex has the highest abundance. They are less common elsewhere but are also expressed at very low levels in CNS astrocytes and oligodendrocytes.
Neurofibrillary tangleNeurofibrillary tangles (NFTs) are aggregates of hyperphosphorylated tau protein that are most commonly known as a primary biomarker of Alzheimer's disease. Their presence is also found in numerous other diseases known as tauopathies. Little is known about their exact relationship to the different pathologies. Neurofibrillary tangles are formed by hyperphosphorylation of a microtubule-associated protein known as tau, causing it to aggregate, or group, in an insoluble form.
Protein phosphorylationProtein phosphorylation is a reversible post-translational modification of proteins in which an amino acid residue is phosphorylated by a protein kinase by the addition of a covalently bound phosphate group. Phosphorylation alters the structural conformation of a protein, causing it to become either activated or deactivated, or otherwise modifying its function. Approximately 13000 human proteins have sites that are phosphorylated. The reverse reaction of phosphorylation is called dephosphorylation, and is catalyzed by protein phosphatases.
Alzheimer's diseaseAlzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens, and is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems with language, disorientation (including easily getting lost), mood swings, loss of motivation, self-neglect, and behavioral issues. As a person's condition declines, they often withdraw from family and society.
Frontotemporal lobar degenerationFrontotemporal lobar degeneration (FTLD) is a pathological process that occurs in frontotemporal dementia. It is characterized by atrophy in the frontal lobe and temporal lobe of the brain, with sparing of the parietal and occipital lobes. Common proteinopathies that are found in FTLD include the accumulation of tau proteins and TAR DNA-binding protein 43 (TDP-43). Mutations in the C9orf72 gene have been established as a major genetic contribution of FTLD, although defects in the granulin (GRN) and microtubule-associated proteins (MAPs) are also associated with it.
Lewy bodyLewy bodies are the inclusion bodies – abnormal aggregations of protein – that develop inside nerve cells affected by Parkinson's disease (PD), the Lewy body dementias (Parkinson's disease dementia and dementia with Lewy bodies (DLB)), and some other disorders. They are also seen in cases of multiple system atrophy, particularly the parkinsonian variant (MSA-P). Lewy bodies appear as spherical masses in the cytoplasm that displace other cell components. For instance, some Lewy bodies tend to displace the nucleus to one side of the cell.
Cell cultureCell culture or tissue culture is the process by which cells are grown under controlled conditions, generally outside of their natural environment. The term "tissue culture" was coined by American pathologist Montrose Thomas Burrows. This technique is also called micropropagation. After the cells of interest have been isolated from living tissue, they can subsequently be maintained under carefully controlled conditions. They need to be kept at body temperature (37 °C) in an incubator.
NeuroregenerationNeuroregeneration involves the regrowth or repair of nervous tissues, cells or cell products. Neuroregenerative mechanisms may include generation of new neurons, glia, axons, myelin, or synapses. Neuroregeneration differs between the peripheral nervous system (PNS) and the central nervous system (CNS) by the functional mechanisms involved, especially in the extent and speed of repair. When an axon is damaged, the distal segment undergoes Wallerian degeneration, losing its myelin sheath.
Nerve injuryNerve injury is an injury to nervous tissue. There is no single classification system that can describe all the many variations of nerve injuries. In 1941, Seddon introduced a classification of nerve injuries based on three main types of nerve fiber injury and whether there is continuity of the nerve. Usually, however, peripheral nerve injuries are classified in five stages, based on the extent of damage to both the nerve and the surrounding connective tissue, since supporting glial cells may be involved.
O-GlcNAcO-GlcNAc (short for O-linked GlcNAc or O-linked β-N-acetylglucosamine) is a reversible enzymatic post-translational modification that is found on serine and threonine residues of nucleocytoplasmic proteins. The modification is characterized by a β-glycosidic bond between the hydroxyl group of serine or threonine side chains and N-acetylglucosamine (GlcNAc).