Muscle arms

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Muscle arms are body wall muscle (BWM) membrane extensions that connect the BWMs to the motor axons of the dorsal and ventral nerve cords in the nematode worm C. elegans . Muscle arms were first described in other nematode species by Anton Schneider (1831 1890) in his "Monographie der Nematoden", published in 1866. Subsequent work showed that muscle arms are found in C. elegans and that these structures are abnormal in unc-104, unc-5 and other mutants.

Muscle contractile soft tissue of mammals

Muscle is a soft tissue found in most animals. Muscle cells contain protein filaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell. Muscles function to produce force and motion. They are primarily responsible for maintaining and changing posture, locomotion, as well as movement of internal organs, such as the contraction of the heart and the movement of food through the digestive system via peristalsis.

Membrane thin, film-like structure that separates two fluids, acting either as a selective barrier or a separating structure

A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Biological membranes include cell membranes ; nuclear membranes, which cover a cell nucleus; and tissue membranes, such as mucosae and serosae. Synthetic membranes are made by humans for use in laboratories and industry.

The dorsal nerve cord is a unique feature to chordates, and it is mainly found in the Vertebrata chordate subphylum. The dorsal nerve cord is only one embryonic feature unique to all chordates, among the other four chordate features-- a notochord, a post-anal tail, an endostyle, and pharyngeal slits. The dorsal hollow nerve cord is a hollow cord dorsal to the notochord. It is formed from a part of the ectoderm that rolls, forming the hollow tube. This is important, as it distinguishes chordates from other animal phyla, such as Annelids and Arthropods, which have solid, ventral tubes. The process by which this is performed is called invagination. The cells essentially convolute into the body cavity, arranging themselves on the dorsal plane above the notochord, as mentioned above. The evolutionary explanation to this adaptation from a solid cord to hollow tube is unknown. In vertebrates, the dorsal nerve cord is modified into the central nervous system, which comprises the brain and spinal cord.

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Insulin-like growth factor

The insulin-like growth factors (IGFs) are proteins with high sequence similarity to insulin. IGFs are part of a complex system that cells use to communicate with their physiologic environment. This complex system consists of two cell-surface receptors, two ligands, a family of six high-affinity IGF-binding proteins, as well as associated IGFBP degrading enzymes, referred to collectively as proteases.

<i>Caenorhabditis elegans</i> free-living species of nematode

Caenorhabditis elegans is a free-living, transparent nematode, about 1 mm in length, that lives in temperate soil environments. It is the type species of its genus. The name is a blend of the Greek caeno- (recent), rhabditis (rod-like) and Latin elegans (elegant). In 1900, Maupas initially named it Rhabditides elegans, Osche placed it in the subgenus Caenorhabditis in 1952, and in 1955, Dougherty raised Caenorhabditis to the status of genus.

Howard Robert Horvitz is an American biologist best known for his research on the nematode worm Caenorhabditis elegans, for which he was awarded the 2002 Nobel Prize in Physiology or Medicine, together with Sydney Brenner and John E. Sulston.

Spermatheca

The spermatheca, also called receptaculum seminis, is an organ of the female reproductive tract in insects, e.g. bees, some molluscs, oligochaeta worms and certain other invertebrates and vertebrates. Its purpose is to receive and store sperm from the male or, in the case of hermaphrodites, the male component of the body. Spermathecae can sometimes be the site of fertilization when the oocytes are sufficiently developed.

Netrin

Netrins are a class of proteins involved in axon guidance. They are named after the Sanskrit word "netr", which means "one who guides." Netrins are genetically conserved across nematode worms, fruit flies, frogs, mice, and humans. Structurally, netrin resembles the extracellular matrix protein laminin.

Dauer describes an alternative developmental stage of nematode worms, particularly rhabditids including Caenorhabditis elegans, whereby the larva goes into a type of stasis and can survive harsh conditions. Since the decision to enter the dauer stage is dependent on environmental cues, it represents a classic and well studied example of polyphenism The Dauer state is given other names in the various types of nematodes such as ‘diapause’ or ‘hypobiosis’, but since the C. elegans nematode has become the most studied nematode, the term ‘dauer stage’ or 'dauer larvae' is becoming universally recognised when referring to this state in other free-living nematodes. The dauer stage is also considered to be equivalent to the infective stage of parasitic nematode larvae.

Caenorhabditis briggsae is a small nematode, closely related to Caenorhabditis elegans. The differences between the two species are subtle. The male tail in C. briggsae has a slightly different morphology from C. elegans. Other differences include changes in vulval precursor competence and the placement of the excretory duct opening. C. briggsae is frequently used to study the differences between it and the more intimately understood C. elegans, especially at the DNA and protein sequence level. Several mutant strains of C. briggsae have also been isolated that facilitate genetic analysis of this organism. C. briggsae, like C. elegans, is a hermaphrodite. The genome sequence for C. briggsae was determined in 2003.

Gubernaculum (nematode anatomy) an organ of male nematodes

In nematodes, the gubernaculum is a hardened or sclerotized structure in the wall that guides the protrusion of the spicule during copulation. For example, in Caenorhabditis elegans, spicules serve to open and dilate the vagina of the female and the gubernaculum is a grooved plate in which the spicules move; the gubernaculum is controlled by two erector and two protractor muscles.

Emodepside chemical compound

Emodepside is an anthelmintic drug that is effective against a number of gastrointestinal nematodes, is licensed for use in cats and belongs to the class of drugs known as the octadepsipeptides, a relatively new class of anthelmintic, which are suspected to achieve their anti-parasitic effect by a novel mechanism of action due to their ability to kill nematodes resistant to other anthelmintics.

<i>Caenorhabditis</i> genus of worms

Caenorhabditis is a genus of nematodes which live in bacteria-rich environments like compost piles, decaying dead animals and rotting fruit. The name comes from Greek: caeno- ; rhabditis = rod-like. In 1900, Maupas initially named the species Rhabditis elegans, Osche placed it in the subgenus Caenorhabditis in 1952, and in 1955, Dougherty raised Caenorhabditis to the status of genus.

Nematode phylum of animals with tubular digestive systems with openings at both ends

The nematodes or roundworms constitute the phylum Nematoda. They are a diverse animal phylum inhabiting a broad range of environments. Taxonomically, they are classified along with insects and other moulting animals in the clade Ecdysozoa, and unlike flatworms, have tubular digestive systems with openings at both ends.

Catharine Anastasia Conley was NASA's Planetary Protection Officer from 2006 through 2018.

Daf-16

DAF-16 is the sole ortholog of the FOXO family of transcription factors in the nematode Caenorhabditis elegans. It is responsible for activating genes involved in longevity, lipogenesis, heat shock survival and oxidative stress responses. It also protects C.elegans during food deprivation, causing it to transform into a hibernation - like state, known as a Dauer. DAF-16 is notable for being the primary transcription factor required for the profound lifespan extension observed upon mutation of the insulin-like receptor DAF-2. The gene has played a large role in research into longevity and the insulin signalling pathway as it is located in C. elegans, a successful ageing model organism.

In molecular biology, the calponin family repeat is a 26 amino acid protein domain. Calponin 1 (CNN1) contains three copies of this domain. This domain is also found in vertebrate smooth muscle protein, and a number of other proteins whose physiological role is not yet established, including Drosophila synchronous flight muscle protein SM20, Caenorhabditis elegans unc-87 protein, rat neuronal protein NP25, and an Onchocerca volvulus antigen.

UNC is a set of proteins first identified through a set of screening tests in Caenorhabditis elegans, looking for roundworms with movement problems. Worms with which were un-coordinated were analysed in order to identify the genetic defect. Such proteins include UNC-5, a receptor for UNC-6 which is one of the netrins. Netrins are a class of proteins involved in axon guidance. UNC-5 uses repulsion (genetics) to direct axons while the other netrin receptor UNC-40 attracts axons to the source of netrin production.

OpenWorm is an international open science project to simulate the roundworm Caenorhabditis elegans at the cellular level as a simulation. Although the long-term goal is to model all 959 cells of the C. elegans, the first stage is to model the worm's locomotion by simulating the 302 neurons and 95 muscle cells. This bottom up simulation is being pursued by the OpenWorm community. As of this writing, a physics engine called Sibernetic has been built for the project and models of the neural connectome and a muscle cell have been created in NeuroML format. A 3D model of the worm anatomy can be accessed through the web via the OpenWorm browser. The OpenWorm project is also contributing to develop Geppetto, a web-based multi-algorithm, multi-scale simulation platform engineered to support the simulation of the whole organism.

UNC93A protein-coding gene in the species Homo sapiens

Unc-93 homolog A is a protein that in humans is encoded by the UNC93A gene.

WormBase is an online biological database about the biology and genome of the nematode model organism Caenorhabditis elegans and contains information about other related nematodes. WormBase is used by the C. elegans research community both as an information resource and as a place to publish and distribute their results. The database is regularly updated with new versions being released every two months. WormBase is one of the organizations participating in the Generic Model Organism Database (GMOD) project.

Nematocida parisii, the nematode-killer from Paris, is a species of Microsporidia fungi. It is found in wild isolates of Caenorhabditis elegans. The species replicates in the intestines of C. elegans.

Victor Marc Nigon was a biologist who was first to study the nematode worm Caenorhabditis elegans in the laboratory, with Ellsworth Dougherty, in the 1940s.

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