Define lipid-anchored proteins, Biology

Assignment Help:

A large number of integral proteins in eukaryotes do not traverse the membrane but are anchored in one or other leaflet of the bilayer through covalent attachment to a hydrocarbon chain. Several proteins, having the prion protein the causative  agent  of  mad  cow  disease  are  stably anchored  at  the  cell  surface by  covalent  linkage  of their  C-terminal  amino  acid  to the  headgroup  of a   phosphatidylinositol   lipid   by   an   ethanolamine-phosphate-trimannose-glucosamine   bridge,  so-called GPI (glycosyl  phosphatidylinositol)-anchored proteins. This difficult structure is built up by sequential addition of the individual sugar residues and ethanolamine phosphate to phosphatidylinositol. The C-terminal hydrophobic signal peptide is deleted from the protein in the lumen of the RER and the preformed GPI anchor added to the new exposed C- terminal amino acid.

2294_22.png

 

figure: Lipid-modified proteins. (a) A glycosyl phosphatidylinositol-anchored protein (G, glucosamine; M, mannose; EtP, ethanolamine phosphate); (b) A myristoylated protein; (c) A prenylated protein; (d) a palmitoylated protein. Some proteins are also customized on Cys residues with covalently attached palmitate (C16:0) (palmitoylated proteins). These have some with membrane-spanning polypeptides (fig. 2d), some prenylated proteins and some myristoylated  proteins. Various of the proteins having in cell signaling, like as the G proteins and the Ras family of proteins are lipid modified.

 

 


Related Discussions:- Define lipid-anchored proteins

Gram positive & gram negative bacteria , What is the difference among Gram ...

What is the difference among Gram positive & Gram negative bacteria based on cell content? Ans) The cell membrane is made if more of lipoproteins in gram negative compared to gr

What are the epithelial tissues, Q. What are the epithelial tissues? What i...

Q. What are the epithelial tissues? What is their general function and how is that function associated to the features of the tissue? Epithelial tissues also called as epitheli

Biological species concept, Is the biological species concept subjective or...

Is the biological species concept subjective or objective? How about the phylogenetic species concept or is it subjective or objective?

Does the environment exert an influence on the phenotype, Does the environm...

Does the environment exert an influence on the phenotype? A phenotype may be changed (compared to the original situation conditioned by its genotype) by nongenetic means. Examp

Determine the genotypes of parents, In humans, the recessive allele that ca...

In humans, the recessive allele that causes a form of red-green colour blindness (c) is found on the X chromosome. a) Determine the genotypes and phenotypes of the F1 generation fr

Endosperm Haustoria, Explain the presence of haustoria in nuclear and helob...

Explain the presence of haustoria in nuclear and helobial endosperm

Leukemia and explain why each finding occurs in this disease, Patient is a ...

Patient is a 7-year-old girl who was brought to her physician by her mother with complaints of general fatigue, anorexia, and unexplained bruises and "rash" for the past 2 weeks. C

Explain structural proteins, Explain Structural protiens Structural pro...

Explain Structural protiens Structural proteins are fibrous proteins. The most familiar of the fibrous proteins are probably the  keratins, which form the protective covering o

Define the term parasite -giardia, Normal 0 false false fal...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

How does refrigeration help to stop food from going bad, How does refrigera...

How does refrigeration help to stop food from going bad?   Western diets are often unhealthy due to they have too much sugar and fat, and not sufficient fibre.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd