cellular component
component of a cell
cell membrane
structure that delimits all living cells
TOM complex
large mitochondrial outer membrane translocase complex that mediates transport of proteins into mitochondrial compartments. TOM transports beta-barrel precursors across the outer membrane and the sorting and assembly machinery (SAM complex) inserts
organelle
organized cell-level biological structure of distinctive morphology and function
gap junction
cell-cell junction comprised of innexins or connexins, two different families of channel-forming proteins. Other proteins may also be present.
S-layer
part of the cell envelope found in almost all archaea and in many types of bacteria
Barr body
structure found in a female mammalian cell containing an unpaired X chromosome that has become densely heterochromatic, silenced and localized at the nuclear periphery
plasmodesma
fine cytoplasmic channel in higher plants that connects the cytoplasm of one cell to that of an adjacent cell
pollen tube
tubular cell projection that is part of a pollen tube cell and extends from a pollen grain
origin recognition complex
multisubunit complex that is located at the replication origins of a chromosome
T-tubule
invagination of the plasma membrane of a muscle cell that extends inward from the cell surface around each myofibril; the ends of T-tubules make contact with the sarcoplasmic reticulum membrane
postsynaptic density
electron-dense network of proteins within and adjacent to the postsynaptic membrane of an asymetric, neuron-neuron synapse
calyx of Held
The terminal specialization of a calyciferous axon which forms large synapses in the mammalian auditory central nervous system.
cell cortex
The region of a cell that lies just beneath the plasma membrane and often, but not always, contains a network of actin filaments and associated proteins.
germ pore
small pore in the outer wall of a fungal spore
Light-harvesting complexes of green plants
Component of photosynthesis
TRAMP complex
multiprotein complex having distributive polyadenylation activity of a variety of RNA substrates including hypomodified and incorrectly folded tRNAs, pre-snRNAs, pre-snoRNAs, incorrectly spliced or processed pre-mRNAs, cryptic unstable transcripts
actomyosin
protein complex of actin and myosin in muscle
nuclear speck
discrete extra-nucleolar subnuclear domain, 20-50 in number, in which splicing factors are seen to be localized by immunofluorescence microscopy
nucleoplasm
that part of the nuclear content other than the chromosomes or the nucleolus
nucleoplasm
that part of the nuclear content other than the chromosomes or the nucleolus
platelet alpha granule
secretory organelle found in blood platelets, which is unique in that it exhibits further compartmentalization and acquires its protein content via two distinct mechanisms: (1) biosynthesis predominantly at the megakaryocyte (MK) level (with some v
DNA replication factor C complex
complex that loads the DNA polymerase processivity factor proliferating cell nuclear antigen (PCNA) onto DNA, thereby permitting processive DNA synthesis catalyzed by DNA polymerase. In eukaryotes the complex consists of five polypeptides
F-actin capping protein complex
heterodimer consisting of alpha and beta subunits that binds to and caps the barbed ends of actin filaments, thereby regulating the polymerization of actin monomers but not severing actin filaments
collagen anchoring fibril
specialised collagen fibril that functions as an anchor, binding to other collagen structures
ferritin complex
protein complex that binds iron and acts as a major iron storage system
photosystem
structural units of protein involved in photosynthesis
sperm head
part of the late spermatid or spermatozoon that contains the nucleus and acrosome
Type IV filament
family of cell projections including T2SS and T4P
intracellular space
interior space of the plasma membrane