Slime mold or slime mould is an informal name given to a polyphyletic assemblage of unrelated eukaryotic organisms in the Stramenopiles, Rhizaria, Discoba, Amoebozoa and Holomycota clades. Most are microscopic; those in the Myxogastria form larger plasmodial slime molds visible to the naked eye. The slime mold life cycle includes a free-living single-celled stage and the formation of spores. Spores are often produced in macroscopic multicellular or multinucleate fruiting bodies that may be formed through aggregation or fusion; aggregation is driven by chemical signals called acrasins. Slime molds contribute to the decomposition of dead vegetation; some are parasitic.
The dictyostelids or cellular slime molds are a group of slime molds or social amoebae.
Mycetozoa is a polyphyletic grouping of slime molds. It was originally thought to be a monophyletic clade, but recently it was discovered that protostelia are a polyphyletic group within Conosa.
Dictyostelium is a genus of single- and multi-celled eukaryotic, phagotrophic bacterivores. Though they are Protista and in no way fungal, they traditionally are known as "slime molds". They are present in most terrestrial ecosystems as a normal and often abundant component of the soil microflora, and play an important role in the maintenance of balanced bacterial populations in soils.
Programmed cell death is the death of a cell as a result of events inside of a cell, such as apoptosis or autophagy. PCD is carried out in a biological process, which usually confers advantage during an organism's lifecycle. For example, the differentiation of fingers and toes in a developing human embryo occurs because cells between the fingers apoptose; the result is that the digits are separate. PCD serves fundamental functions during both plant and animal tissue development.
Cell migration is a central process in the development and maintenance of multicellular organisms. Tissue formation during embryonic development, wound healing and immune responses all require the orchestrated movement of cells in particular directions to specific locations. Cells often migrate in response to specific external signals, including chemical signals and mechanical signals. Errors during this process have serious consequences, including intellectual disability, vascular disease, tumor formation and metastasis. An understanding of the mechanism by which cells migrate may lead to the development of novel therapeutic strategies for controlling, for example, invasive tumour cells.
Mitogen Activated Protein (MAP) kinase kinase kinase is a serine/threonine-specific protein kinase which acts upon MAP kinase kinase. Subsequently, MAP kinase kinase activates MAP kinase. Several types of MAPKKK can exist but are mainly characterized by the MAP kinases they activate. MAPKKKs are stimulated by a large range of stimuli, primarily environmental and intracellular stressors. MAPKKK is responsible for various cell functions such as cell proliferation, cell differentiation, and apoptosis. The duration and intensity of signals determine which pathway ensues. Additionally, the use of protein scaffolds helps to place the MAPKKK in close proximity with its substrate to allow for a reaction. Lastly, because MAPKKK is involved in a series of several pathways, it has been used as a therapeutic target for cancer, amyloidosis, and neurodegenerative diseases. In humans, there are at least 19 genes which encode MAP kinase kinase kinases:
The MAPK/ERK pathway is a chain of proteins in the cell that communicates a signal from a receptor on the surface of the cell to the DNA in the nucleus of the cell.
Phenoptosis is a conception of the self-programmed death of an organism proposed by Vladimir Skulachev in 1999.
Transcription factor Jun is a protein that in humans is encoded by the JUN gene. c-Jun, in combination with protein c-Fos, forms the AP-1 early response transcription factor. It was first identified as the Fos-binding protein p39 and only later rediscovered as the product of the JUN gene. c-jun was the first oncogenic transcription factor discovered. The proto-oncogene c-Jun is the cellular homolog of the viral oncoprotein v-jun. The viral homolog v-jun was discovered in avian sarcoma virus 17 and was named for ju-nana, the Japanese word for 17. The human JUN encodes a protein that is highly similar to the viral protein, which interacts directly with specific target DNA sequences to regulate gene expression. This gene is intronless and is mapped to 1p32-p31, a chromosomal region involved in both translocations and deletions in human malignancies.
Each species of slime mold has its own specific chemical messenger, which are collectively referred to as acrasins. These chemicals signal that many individual cells aggregate to form a single large cell or plasmodium. One of the earliest acrasins to be identified was cyclic AMP, found in the species Dictyostelium discoideum by Brian Shaffer, which exhibits a complex swirling-pulsating spiral pattern when forming a pseudoplasmodium.
Cysteine-rich angiogenic inducer 61 (CYR61) or CCN family member 1 (CCN1), is a matricellular protein that in humans is encoded by the CYR61 gene.
Radiation-inducible immediate-early gene IEX-1 is a protein that in humans is encoded by the IER3 gene.
Dictyostelium discoideum is a species of soil-dwelling amoeba belonging to the phylum Amoebozoa, infraphylum Mycetozoa. Commonly referred to as slime mold, D. discoideum is a eukaryote that transitions from a collection of unicellular amoebae into a multicellular slug and then into a fruiting body within its lifetime. Its unique asexual life cycle consists of four stages: vegetative, aggregation, migration, and culmination. The life cycle of D. discoideum is relatively short, which allows for timely viewing of all stages. The cells involved in the life cycle undergo movement, chemical signaling, and development, which are applicable to human cancer research. The simplicity of its life cycle makes D. discoideum a valuable model organism to study genetic, cellular, and biochemical processes in other organisms.
Safingol is a lyso-sphingolipid protein kinase inhibitor. It has the molecular formula C18H39NO2 and is a colorless solid. Medicinally, safingol has demonstrated promising anticancer potential as a modulator of multi-drug resistance and as an inducer of necrosis. The administration of safingol alone has not been shown to exert a significant effect on tumor cell growth. However, preclinical and clinical studies have shown that combining safingol with conventional chemotherapy agents such as fenretinide, vinblastine, irinotecan and mitomycin C can dramatically potentiate their antitumor effects. In phase I clinical trials, it was found to be safe to co-administer with cisplatin, but caused reversible dose-dependent hepatotoxicity.
Chemorepulsion is the directional movement of a cell away from a substance. Of the two directional varieties of chemotaxis, chemoattraction has been studied to a much greater extent. Only recently have the key components of the chemorepulsive pathway been elucidated. The exact mechanism is still being investigated, and its constituents are currently being explored as likely candidates for immunotherapies.
Bacillus subtilis is a rod-shaped, Gram-positive bacteria that is naturally found in soil and vegetation, and is known for its ability to form a small, tough, protective and metabolically dormant endospore. B. subtilis can divide symmetrically to make two daughter cells, or asymmetrically, producing a single endospore that is resistant to environmental factors such as heat, desiccation, radiation and chemical insult which can persist in the environment for long periods of time. The endospore is formed at times of nutritional stress, allowing the organism to persist in the environment until conditions become favourable. The process of endospore formation has profound morphological and physiological consequences: radical post-replicative remodelling of two progeny cells, accompanied eventually by cessation of metabolic activity in one daughter cell and death by lysis of the other.
mTORC1, also known as mammalian target of rapamycin complex 1 or mechanistic target of rapamycin complex 1, is a protein complex that functions as a nutrient/energy/redox sensor and controls protein synthesis.
N2a cells are a fast-growing mouse neuroblastoma cell line.
Apoptosis-inducing factor, mitochondria-associated 3 is a protein that in humans is encoded by the AIFM3 gene.
