PMID: 11983428

 

    Legend: Gene, Sites

Title : Stromal interaction molecule 1 ( STIM1 ), a transmembrane protein with growth suppressor activity, contains an extracellular SAM domain modified by N-linked glycosylation

Abstract :
  1. Stromal interaction molecule 1 ( STIM1 ) is a cell surface transmembrane glycoprotein implicated in tumour growth control and stromal-haematopoietic cell interactions
  2. A single sterile alpha motif ( SAM ) protein- protein interaction domain is modelled within its extracellular region , a subcellular localisation not previously described for other SAM domain-containing proteins
  3. We have defined the transmembrane topology of STIM1 by determining the sites of N-linked glycosylation
  4. We have confirmed that STIM1 is modified by N-linked glycosylation at two sites within the SAM domain itself, deduced as asparagine residues N131 and N171 , demonstrating that STIM1 is translocated across the membrane of the endoplasmic reticulum such that the SAM domain resides within the endoplasmic reticulum (ER) lumen
  5. Both N-linked oligosaccharides remain endoglycosidase H-sensitive, indicating absence of full processing within the ER and Golgi
  6. This immature modification is nevertheless sufficient and critical for cell surface expression of STIM1
  7. We show that STIM1- STIM1 homotypic interactions are mediated via the cytoplasmic rather than the extracellular region of STIM1 , excluding an essential role for the SAM domain in these protein interactions
  8. These studies provide the first evidence for an extracellular localisation of a SAM domain within any protein , and the first example of a SAM domain modified by N-linked glycosylation
Output (sent_index, trigger, protein, sugar, site):
  • 1. glycoprotein, , Stromal interaction molecule 1, -, -
  • 1. glycoprotein, , glycoprotein, -, -
  • 3. glycosylation, , -, -, sites
  • 4. glycosylation, , -, -, sites
  • 4. residues, , -, -, asparagine residues N131 and N171
Output(Part-Of) (sent_index, protein, site):
  • 0. STIM1, domain
  • 0. Stromal interaction molecule 1, domain
  • 0. protein, domain
  • 2. SAM, domain
  • 2. protein, domain
*Output_Site_Fusion* (sent_index, protein, sugar, site):
  • 4. Stromal interaction molecule 1, -, asparagine residues N131 and N171

 

 

Protein NCBI ID SENTENCE INDEX
STIM1 6786 0,1,3,4,6,7
Stromal interaction molecule 1 6786 0,1