Title : N-linked glycosylation is required for optimal function of Kaposi's sarcoma herpesvirus-encoded, but not cellular,
interleukin 6
Abstract :
- Kaposi's sarcoma-associated herpesvirus interleukin-6 ( vIL-6) is a structural and functional homologue of the human cytokine IL-6 ( hIL-6 )
- hIL-6 and vIL-6 exhibit similar biological functions and both act via the gp130 receptor subunit to activate the Janus tyrosine kinase ( JAK)1 and signal transducer and activator of transcription ( STAT)1 /3 pathway
- Here we show that vIL-6 is N-linked glycosylated at N78 and N89 and demonstrate that N-linked glycosylation at site N89 of vIL-6 markedly enhances binding to gp130 , signaling through the JAK1- STAT1 /3 pathway and functions in a cytokine-dependent cell proliferation bioassay
- Although hIL-6 is also N-glycosylated at N73 and multiply O-glycosylated, neither N-linked nor O-linked glycosylation is necessary for IL-6 receptor alpha-dependent binding to gp130 or signaling through JAK1- STAT1 /3
- As distinct from vIL-6, unglycosylated hIL-6 is as potent as glycosylated hIL-6 in stimulating B cell proliferation
- These findings highlight distinct functional roles of N-linked glycosylation in viral and cellular IL-6
Output (sent_index, trigger,
protein,
sugar,
site):
- 0. glycosylation, , interleukin 6, -, -
- 3. glycosylation, , -, -, N89
- 4. N-glycosylated, , hIL-6, -, N73
- 4. O-glycosylated, , hIL-6, -, -
- 5. glycosylated, , hIL-6, -, -
- 5. unglycosylated, , hIL-6, -, -
Output(Part-Of) (sent_index,
protein,
site):
*Output_Site_Fusion* (sent_index,
protein,
sugar,
site):
- 3. vIL, -, N89
- 4. hIL-6, -, N73