cellular component
component of a cell
voltage-gated calcium channel complex
protein complex that forms a transmembrane channel through which calcium ions may pass in response to changes in membrane potential
apical complex
group of cytoskeletal structures and associated membrane-bounded organelles found at the anterior end of adult obligate intracellular protozoan parasites in the phylum Apicomplexa. The apical complex is involved in attachment to and penetration of
AP-type membrane coat adaptor complex
Any of several heterotetrameric complexes that link clathrin (or another coat-forming molecule, as hypothesized for AP-3 and AP-4) to a membrane surface; they are found on coated pits and coated vesicles, and mediate sorting of cargo proteins into ve
histone locus body
nuclear body associated with the histone gene locus that is thought to contain all of the factors necessary for histone mRNA transcription and pre-mRNA processing. In Drosophila, U7 snRNP is located in the histone locus body rather than the distinc
vitelline envelope
glycoprotein-based structure that lies outside the plasma membrane and surrounds the egg before fertilization
egg chorion
protective, noncellular membrane that surrounds the eggs of various animals including insects and fish
viral synapse
type of cellular junction
nucleus
membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated
chloroplast
chlorophyll-containing plastid with thylakoids organized into grana and frets, or stroma thylakoids, and embedded in a stroma
pseudopodium
protrusion of a cell, associated with movements of the protoplasm, and serving for locomotion and feeding
elastic fiber
extracellular matrix part that consists of an insoluble core of polymerized tropoelastin monomers and a surrounding mantle of microfibrils
light-harvesting complex
protein-pigment complex that may be closely or peripherally associated to photosynthetic reaction centers that participate in harvesting and transferring radiant energy to the reaction center
fibrinogen complex
protein complex found in blood plasma and involved in clot formation
membrane raft
small sterol- and sphingolipid-enriched membrane domains that compartmentalize cellular processes
axon hillock
Portion of the neuronal cell soma from which the axon originates.
microtubule organizing center
intracellular structure that can catalyze gamma-tubulin-dependent microtubule nucleation and anchor microtubules
pilus
proteinaceous hair-like appendage on the surface of bacteria ranging from 2-8 nm in diameter
middle lamella
part of a plant
Lewy body
spherical inclusion commonly found in damaged neurons
terminal bouton
nerve fiber part
brush border
Brush Border Epithelium
aster
cellular structure shaped like a star
apical dendrite
dendrite that emerges near the apical pole of a neuron. In bipolar neurons, apical dendrites are located on the opposite side of the soma from the axon
intracellular anatomical structure
living contents of a cell; the matter contained within (but not including) the plasma membrane, usually taken to exclude large vacuoles and masses of secretory or ingested material. In eukaryotes it includes the nucleus and cytoplasm.
death-inducing signaling complex
protein complex formed by the association of signaling proteins with a death receptor upon ligand binding. The complex includes procaspases and death domain-containing proteins in addition to the ligand-bound receptor, and may control the activatio
meiotic nuclear membrane microtubule tethering complex
protein complex that spans the nuclear outer and inner membranes, thereby linking the major cytoplasmic cytoskeleton elements to the nuclear lumen; the complex is conserved in eukaryotes and contains proteins with SUN and KASH domains
Lamina lucida
layer of the skin
dendrite
neuron projection that conducts a nerve impulse towards the axon or the cell body
cytoplasmic stress granule
dense aggregation in the cell cytosol composed of proteins and RNAs that appear when the cell is under stress
pore complex
any small opening in a membrane that allows the passage of gases and/or liquids
nuclear inner membrane
The inner, i.e. lumen-facing, lipid bilayer of the nuclear envelope.
SCAR complex
pentameric complex that includes orthologues of human PIR121, Nap1, Abi, SCAR, and HSPC300 and regulates actin polymerization and/or depolymerization through small GTPase mediated signal transduction
RISC complex
ribonucleoprotein complex central to RNA interference
signal recognition particle receptor complex
transmembrane heterodimeric protein located in the membrane of the rough endoplasmic reticulum. Both subunits contain GTPase domains with which signal recognition particle interacts. In the presence of GTP and SRP receptor, SRP is released from the
mitochondrial ribosome
ribosome found in the mitochondrion of a eukaryotic cell
respiratory chain complex I
enzyme of the respiratory chain consisting of several polypeptide chains and L-shaped, with a horizontal arm lying in the membrane and a vertical arm that projects into the matrix.
basement membrane
thin layer of dense material found in tissues between cells and the adjacent connective tissue
mitochondrion
organelle in eukaryotic cells responsible for respiration
ion channel complex
pore-forming membrane protein that allows the passage of ions through a membrane
cytoplasm
all of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures
centrosome
cell organelle in animal cell helping in cell division
Y chromosome
sex chromosome in the XY sex-determination system
microfibril
extracellular matrix components occurring independently or along with elastin
photosynthetic reaction centre
molecular unit responsible for absorbing light in photosynthesis
nuclear lamina
The fibrous, electron-dense layer lying on the nucleoplasmic side of the inner membrane of a cell nucleus, composed of lamin filaments. The polypeptides of the lamina are thought to be concerned in the dissolution of the nuclear envelope and its re-f
Auer rod
large, crystalline cytoplasmic inclusion bodies sometimes observed in myeloid blast cells
neurofilament
type of intermediate filament found in the core of neuronal axons. Neurofilaments are heteropolymers composed of three type IV polypeptides: NF-L, NF-M, and NF-H (for low, middle, and high molecular weight). Neurofilaments are responsible for the r
nucleolus organizer region
region of a chromosome where nucleoli form during interphase, and where genes encoding the largest rRNA precursor transcript are tandemly arrayed
viral envelope
outermost layer of many types of viruses
bacterial capsule
polysaccharide layer that lies outside the cell envelope in many bacteria