Major intrinsic proteins

Major intrinsic protein
Structure of a glycerol-conducting channel.[1]
Identifiers
Symbol	MIP
Pfam	PF00230
InterPro	IPR000425
PROSITE	PDOC00193
SCOP	1fx8
TCDB	1.A.8
OPM family	7
OPM protein	1z98
Available protein structures: Pfam structures PDB RCSB PDB; PDBe PDBsum structure summary

Major intrinsic proteins are a large family of transmembrane protein channels that are grouped together on the basis of sequence similarities^[2][3][4][5]. Proteins from this family exhibit essentially two distinct types of channel properties: (1) specific water transport by the aquaporins, and (2) small neutral solutes transport, such as glycerol by the glycerol facilitators.

Examples

MIP family includes the following channels:

• Mammalian major intrinsic protein (MIP). MIP is the major component of lens fibre gap junctions.
• Mammalian aquaporins^[5]. These proteins form water- specific channels that provide the plasma membranes of red cells and kidney prox imal and collecting tubules with high permeability to water, thereby permitting water to move in the direction of an osmotic gradient.
• Soybean nodulin-26, a major component of the peribacteroid membrane induced during nodulation in legume roots after Rhizobium infection.
• Plants tonoplast intrinsic proteins (TIP). There are various isoforms of TIP : alpha (seed), gamma, Rt (root), and Wsi (water-stress induced). These proteins may allow the diffusion of water, amino acids and/or peptides from the tonoplast interior to the cytoplasm..
• Bacterial glycerol facilitator protein (gene glpF), which facilitates the movement of glycerol across the cytoplasmic membrane.
• Salmonella typhimurium propanediol diffusion fac ilitator (gene pduF).
• Yeast FPS1, a glycerol uptake/efflux facilitator protein.
• Drosophila neurogenic protein 'big brain' (bib). This protein may mediate in tercellular communication; it may functions by allowing the transport of certain molecules(s) and thereby sending a signal for an exodermal cell to become an ep idermoblast instead of a neuroblast.
• Yeast hypothetical protein YFL054c.
• A hypothetical protein from the pepX region of Lactococcus lactis.

Structure

MIP family proteins are thought to contain 6 TM domains. Sequence analysis suggests that the proteins may have arisen through tandem, intragenic duplication from an ancestral protein that contained 3 TM domains^[6].

Some of the proteins in this group are responsible for the molecular basis of the blood group antigens, surface markers on the outside of the red blood cell membrane. Most of these markers are proteins, but some are carbohydrates attached to lipids or proteins^[7]. Aquaporin-CHIP (Aquaporin 1) belongs to the Colton blood group system and is associated with Co(a/b) antigen.

Subfamilies

• Aquaporin IPR012269

Human proteins containing this domain

AQP1, AQP2, AQP3, AQP4, AQP5, AQP6, AQP7, AQP8, AQP9, AQP10, MIP

References

1. ^ Fu D, Libson A, Miercke LJ, et al. (October 2000). "Structure of a glycerol-conducting channel and the basis for its selectivity". Science 290 (5491): 481–6. doi:10.1126/science.290.5491.481. PMID 11039922. 
2. ^ Reizer J, Reizer A, Saier Jr MH (1993). "The MIP family of integral membrane channel proteins: sequence comparisons, evolutionary relationships, reconstructed pathway of evolution, and proposed functional differentiation of the two repeated halves of the proteins". Crit. Rev. Biochem. Mol. Biol. 28 (3): 235–257. doi:10.3109/10409239309086796. PMID 8325040. 
3. ^ Pao GM, Johnson KD, Chrispeels MJ, Sweet G, Sandal NN, Wu LF, Saier Jr MH, Hofte H (1991). "Evolution of the MIP family of integral membrane transport proteins". Mol. Microbiol. 5 (1): 33–37. doi:10.1111/j.1365-2958.1991.tb01823.x. PMID 2014003. 
4. ^ Wistow GJ, Pisano MM, Chepelinsky AB (1991). "Tandem sequence repeats in transmembrane channel proteins". Trends Biochem. Sci. 16 (5): 170–171. doi:10.1016/0968-0004(91)90065-4. PMID 1715617. 
5. ^ ^{a b} Chrispeels MJ, Agre P (1994). "Aquaporins: water channel proteins of plant and animal cells". Trends Biochem. Sci. 19 (10): 421–425. doi:10.1016/0968-0004(94)90091-4. PMID 7529436. 
6. ^ . pp. -. 
7. ^ Reid ME, Lomas-francis C (2002). "Molecular approaches to blood group identification". Curr Opin Hematol 9 (2): 152–159. doi:10.1097/00062752-200203000-00012. PMID 11845000. 

This membrane protein-related article is a stub. You can help Wikipedia by expanding it.v · Categories: Protein domains Protein families Transmembrane proteins Membrane protein stubs Wikimedia Foundation. 2010. Игры ⚽ Поможем написать реферат XEANT-AM I Remember Look at other dictionaries: major intrinsic protein — Family of structurally related proteins with 6 transmembrane segments, associated with gap junctions or vacuoles. MIP is found in lens fibre gap junctions. Other members: nodulin 26 (soybean), tonoplast intrinsic protein (TIP) found in plant… …   Dictionary of molecular biology Aquaporin — Aquaporins are integral membrane proteins from a larger family of major intrinsic proteins (MIP) that form pores in the membrane of biological cells.cite journal | author = Agre P | title = The aquaporin water channels | journal = Proc Am Thorac… …   Wikipedia Аквапорин — Струкутра молекулы Аквапорина 1 Аквапорины интегральные мембранные белки, формирующие поры в мембранах клеток. Семейство аквапоринов входит в более крупное семейство основных вну …   Википедия Основные внутренние белки — (англ. Major intrinsic proteins) большое семейство трансмембранных белковых каналов, объединённых на основе сходства аминокислотной последовательности. [1][2][3][4] Белки этого семейства обладают двумя основными характеристиками каналов: (1) …   Википедия MIP (gene) — Major intrinsic protein of lens fiber, also known as MIP, is a human gene.cite web | title = Entrez Gene: MIP major intrinsic protein of lens fiber| url = http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene Cmd=ShowDetailView TermToSearch=4284|… …   Wikipedia cell — cell1 cell like, adj. /sel/, n. 1. a small room, as in a convent or prison. 2. any of various small compartments or bounded areas forming part of a whole. 3. a small group acting as a unit within a larger organization: a local cell of the… …   Universalium lipid — /lip id, luy pid/, n. Biochem. any of a group of organic compounds that are greasy to the touch, insoluble in water, and soluble in alcohol and ether: lipids comprise the fats and other esters with analogous properties and constitute, with… …   Universalium Protein — A large molecule composed of one or more chains of amino acids in a specific order determined by the base sequence of nucleotides in the DNA coding for the protein. Proteins are required for the structure, function, and regulation of the body s… …   Medical dictionary Cholesterylester transfer protein — Cholesteryl ester transfer protein, plasma PDB rendering based on 2obd …   Wikipedia List of gene families — This is a list of gene families or gene complexes, that is sets of genes which occur across a number of different species which often serve similar biological functions. These gene families typically encode functionally related proteins, and… …   Wikipedia 18+ © Academic, 2000-2024 Contact us: Technical Support, Advertising Dictionaries export, created on PHP, Joomla, Drupal, WordPress, MODx. Mark and share Search through all dictionaries Translate… Search Internet Share the article and excerpts Direct link … Do a right-click on the link above and select “Copy Link”