The SH2 domain binds strongly to short target peptides containing a critical four-residue core sequence:: 

phosphotyrosine–glutamic acid–glutamic acid–isoleucine

TLS Online TPP Program

#Id: 7953

#XL - Q Biochemistry

Tunicamycin

blocks the first enzyme in this pathway, inhibits the synthesis of all N-linked oligosaccharides in cells.

TLS Online TPP Program

#Id: 7952

#XL - Q Biochemistry

Two N- acetylglucosamine (GlcNAc) and five mannose residues are added one at a time to a dolichol phosphate on the cytosolic face of the ER membrane

TLS Online TPP Program

#Id: 7951

#XL - Q Biochemistry

First sugar residue is attached to dolichol by a high-energy pyrophosphate linkage & the other sugars are added by glycosidic bonds

TLS Online TPP Program

#Id: 7950

#XL - Q Biochemistry

Prior to transfer to a nascent chain in the lumen of the  ER, the oligosaccharide precursor is assembled on amembrane- attached anchor called dolichol phosphate, a longchain polyisoprenoid lipid

TLS Online TPP Program

#Id: 7949

#XL - Q Biochemistry

A branched oligosaccharide containing

3 glucose (Glc)

9 mannose (Man)

2 N-acetylglucosamine (GlcNAc)

Glc3Man9(GlcNAc)2

TLS Online TPP Program

#Id: 7948

#XL - Q Biochemistry

Biosynthesis of all N-linked oligosaccharides begins in the rough ER with a preformed oligosaccharide precursor containing 14 residues.