Cisterna

For other uses, see Cisterna (disambiguation).

A cisterna (plural cisternae) refers to a flattened membrane disk that makes up the endoplasmic reticulum and Golgi apparatus. A Golgi stack may contain anywhere from three to twenty cisternae but most contain about six. Golgi cisternae can be separated into four classes; cis, medial, trans, and TGN (trans-Golgi network).^[1] Each cisternae class contain different enzymes working within it. This helps to prevent any two reactions form competing.^[1] Almost all cisternae in the Golgi apparatus present multiple stacking. There are only eight instances in which the stacked characteristic has been lost.^[2]

Function

Cisternae pack and modify proteins and polysaccharides. Biosynthetic cargo proteins travel through cisternae and undergo glycan remodeling and other modifications. Cisternae package the proteins and then send them to transport carriers. They also package polysaccharides that are synthesized in the Golgi apparatus. The compounds enter at the cis face of the Golgi stack and exit out the trans side where most of the packaging occurs.^[1]

The functions of cisternae change as it undergoes micromaturation. Immature cisternae receive COP2 vesicles from the endoplasmic reticulum.^[3] During this stage, new cisternae can be produced. The next stage begins when cisternae at carbohydrate synthesis swap material via COPI vesicles. This is when glycosylation and polysaccharide synthesis occur. Mature cisternae reach the final stage where cargo proteins are sent to transport carriers and finally the cisternae disassemble.^[1]

Structures of the cell / organelles (TH H1.00.01.2-3)

Endomembrane system	Cell membrane Nucleus Nucleolus Endoplasmic reticulum Golgi apparatus Parenthesome Autophagosome Vesicles Exosome Lysosome Endosome Phagosome Vacuole Acrosome Cytoplasmic granules Melanosome Microbody Glyoxysome Peroxisome Weibel–Palade body

Cytoskeleton	Microfilaments Intermediate filaments Microtubules Prokaryotic cytoskeleton MTOCs Centrosome Centriole Basal body Spindle pole body Myofibril

Endosymbionts	Mitochondrion Plastids Chloroplast Chromoplast Gerontoplast Leucoplast Amyloplast Elaioplast Proteinoplast Tannosome

Other internal	RNA Ribosome Spliceosome Vault Cytoplasm Proteasome

External	Undulipodium Cilium Flagellum Axoneme Radial spoke Extracellular matrix Cell wall

1 2 3 4 Day, Kasey J.; Staehelin, L. Andrew; Glick, Benjamin S. (2013-07-24). "A three-stage model of Golgi structure and function". Histochemistry and Cell Biology 140 (3): 239–249. doi:10.1007/s00418-013-1128-3. ISSN 0948-6143. PMC 3779436. PMID 23881164.
↑ Klute, Mary J.; Melançon, Paul; Dacks, Joel B. (2011-08-01). "Evolution and Diversity of the Golgi". Cold Spring Harbor Perspectives in Biology 3 (8): a007849. doi:10.1101/cshperspect.a007849. ISSN 1943-0264. PMC 3140683. PMID 21646379.
↑ Bankaitis, Vytas A.; Garcia-Mata, Rafael; Mousley, Carl J. "Golgi Membrane Dynamics and Lipid Metabolism". Current Biology 22 (10): R414–R424. doi:10.1016/j.cub.2012.03.004. ISSN 0960-9822. PMC 4059015. PMID 22625862.

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