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

Cell, What is suisidel bag in plant?

What is suisidel bag in plant?

PROTOZOA, WHAT IS THE CLASSIFICATION OF PROTOZOA ..

WHAT IS THE CLASSIFICATION OF PROTOZOA ..

What is loud p2 in second heart, What is Loud P2 in second heart? It oc...

What is Loud P2 in second heart? It occurs in pulmonary hypertension. In absence of pulmonary hypertension, it occurs when pulmonary trunk is dilated as in Ostium Secundum, ASD

Excretion, what are the 3 main excretory produces of mammals?

what are the 3 main excretory produces of mammals?

What is reaction specificity, Reaction specificity Some  enzymes  catal...

Reaction specificity Some  enzymes  catalyze only one  reaction  acting  on  a specific substrate. Example: urease  and  catalase  acts  only  on  urea and  hydrogen peroxide,

What do you mean by polyester, Q. What do you mean by Polyester? Polyes...

Q. What do you mean by Polyester? Polyester (ES) or polyethylene terephthalate (PET): PET is a very strong transparent glossy film, which has good moisture and gas barrier p

What are the different phenotype, What is the genetic condition in which th...

What is the genetic condition in which the heterozygous individual has different phenotype from the homozygous individual? This condition is called lack of dominance and it can

How is opening and closing of stomata controlled, How is opening and closin...

How is opening and closing of stomata controlled? Describe a) Why is the length of a food chain in an ecosystem generally limited to 3 - 4 trophic levels? Explain with an examp

Explain ebb or shock period - dietary management for burn, Explain the Ebb ...

Explain the Ebb or Shock Period - Dietary Management for Burns? During the initial bums after injury, the focus is on counteracting the stress induced neurohormonal and physiol

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