BP

GO:0000086

G2/M transition of mitotic cell cycle

The mitotic cell cycle transition by which a cell in G2 commits to M phase. The process begins when the kinase activity of M cyclin/CDK complex reaches a threshold high enough for the cell cycle to proceed. This is accomplished by activating a positive feedback loop that results in the accumulation of unphosphorylated and active M cyclin/CDK complex.

TAS

BP

GO:0007275

multicellular organism development

The biological process whose specific outcome is the progression of a multicellular organism over time from an initial condition (e.g. a zygote or a young adult) to a later condition (e.g. a multicellular animal or an aged adult).

IEA

BP

GO:0007286

spermatid development

The process whose specific outcome is the progression of a spermatid over time, from its formation to the mature structure.

IEA

CC

GO:0000922

spindle pole

Either of the ends of a spindle, where spindle microtubules are organized; usually contains a microtubule organizing center and accessory molecules, spindle microtubules and astral microtubules.

IEA

CC

GO:0001520

outer dense fiber

A supramolecular fiber found in the flagella of mammalian sperm that surrounds the nine microtubule doublets. These dense fibers are stiff and noncontractile. In human, they consist of about 10 major and at least 15 minor proteins, where all major proteins are ODF1, ODF2 or ODF2-related proteins.

IEA

CC

GO:0005634

nucleus

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

IDA

CC

GO:0005813

centrosome

A structure comprised of a core structure (in most organisms, a pair of centrioles) and peripheral material from which a microtubule-based structure, such as a spindle apparatus, is organized. Centrosomes occur close to the nucleus during interphase in many eukaryotic cells, though in animal cells it changes continually during the cell-division cycle.

IDA

CC

GO:0005814

centriole

A cellular organelle, found close to the nucleus in many eukaryotic cells, consisting of a small cylinder with microtubular walls, 300-500 nm long and 150-250 nm in diameter. It contains nine short, parallel, peripheral microtubular fibrils, each fibril consisting of one complete microtubule fused to two incomplete microtubules. Cells usually have two centrioles, lying at right angles to each other. At division, each pair of centrioles generates another pair and the twin pairs form the pole of the mitotic spindle.

IDA

CC

GO:0005829

cytosol

The part of the cytoplasm that does not contain organelles but which does contain other particulate matter, such as protein complexes.

TAS

CC

GO:0005874

microtubule

Any of the long, generally straight, hollow tubes of internal diameter 12-15 nm and external diameter 24 nm found in a wide variety of eukaryotic cells; each consists (usually) of 13 protofilaments of polymeric tubulin, staggered in such a manner that the tubulin monomers are arranged in a helical pattern on the microtubular surface, and with the alpha/beta axes of the tubulin subunits parallel to the long axis of the tubule; exist in equilibrium with pool of tubulin monomers and can be rapidly assembled or disassembled in response to physiological stimuli; concerned with force generation, e.g. in the spindle.

IEA

CC

GO:0097539

ciliary transition fiber

A nine-bladed, propeller-like protein complex that links the distal end of the basal body and the cilium to the plasma membrane. Functions in protein sorting and gating (i.e. active and passive transport of proteins in and out of the cilium).

IEA

MF

GO:0005198

structural molecule activity

The action of a molecule that contributes to the structural integrity of a complex or assembly within or outside a cell.

TAS

MF

GO:0005515

protein binding

Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules).

IPI