complex Golgi Camillo Golgi was discovered in 1898.This structure is present in the cytoplasm of virtually all eukaryotic (higher organisms components) of the cells, particularly the secretory cells in animals.
Golgi complex.Structure.
structure is a stack of flattened sacs of membranes.They are called cisterns.This stack of bags connected with the system of bubbles (Golgi vesicles).On one end of the stacks of bags is constantly going on the formation of new tanks merger bubbles that bud from the endoplasmic reticulum (network cavities).On the other end of the stack to the inner sides of the tank and complete maturation into bubbles dissolve again.So there is a gradual movement of tanks in the hills to the inner side of the outer side.
The tank structure matures proteins for secretion of transmembrane proteins of the plasma membrane, lysosomes and other proteins.Maturing agent move on tanks in series organelles.In them there is a final folding of proteins and their modifications - phosphorylation and glycosylation.
Plant cells are characterized by the presence of a number of separate dictyosomes (stacks).In animal cells often have multiple stacks connected by tubes or one big pile.
device (complex) Golgi apparatus consists of four main sections: the trans-Golgi network, cis-Golgi, trans Golgi and Golgi media.To attach the structure and also the intermediate compartment (separate area).It contains the accumulation of membrane vesicles between reitkulumom and cis-Golgi.
entire apparatus is the organelle rather polymorphous (diverse).Even at different stages of development of a single cell Golgi complex may have a different look.
differs apparatus and asymmetry.Is located closer to the cell nucleus of the tank (cis-Golgi) contain most immature proteins.To join this tank continuously membrane vesicles - vesicles.In various tanks contained various resident enzymes (catalytic), which suggests that these proteins occur with the maturing consistently different processes.
Golgi complex.Functions.
The tasks include chemical modification of the structure and transport of substances entering into it.Proteins that penetrate into the unit from the endoplasmic reticulum, is a substrate for the enzyme source.After concentration and modification enzymes in vesicles transported to the designated site.For example, this may be the region of formation of the new kidney.With the participation of cytoplasmic microtubules transfer process is carried out most actively.
Golgi complex also performs the task of joining carbohydrate moieties to proteins and subsequent use in the construction of these proteins and cell membranes of lysosomes.
For some algae in the structure of the device the synthesis of cellulose fibers.
Golgi complex functions are quite diverse.Among them we should highlight:
- sorting, removal, accumulation of secretory products.
- accumulation of lipid molecules and the formation of lipoproteins.
- Completion modification of proteins (posttranslational), namely glycosylation, sulfation and others.
- formation of lysosomes.
- participation in the formation of the acrosome.
- polysaccharide synthesis for the formation of waxes, glycoproteins, mucus, gum matrix materials in the cell walls of plants (pectin, hemicellulose, and others).
- contractile vacuole formation in protozoa.
- cell plate formation in plant cells after nuclear fission.
