Features
more than half of the total membrane (in animals)
tubules and flattened sacs
continuous with outer nuclear membrane
the space inside: lumen or cisternal space
ribosomes on it has no differences with those in cytosol
protein synthesis
products
secretory proteins
integral membrane proteins
soluble proteins of organelles (lysosomes, etc.)
glycosylation
half of eukaryotic proteins
N-linked to Asn
by oligosaccharyl tranferase which bound to the membrane
linked to protein translocator（移位蛋白）
oligosaccharide is linked to dolichol（多萜醇）
synthesized outside then filped inside
formation of disulfide bonds
by protein dislfide isomerase (PDI)
quality control of new proteins
chaperones
calnexin（钙联接蛋白）
clareticulin（钙网蛋白）
PDI
GT (glucosyl tranferase，葡糖基转移酶)
ER stress
synthesis of membrane lipids
most lipids are synthesized entirely within ER
except
sphingomyelin
glycolipids
unique lipids in Mit or Chl
asymmetric synthesis
scramblase（混杂酶）
ER
non-specific
flippase（翻转酶）
plasma mambrane
specific
