Differential glycosylation of N‐POMC1–77 regulates the production of γ3‐MSH by purified pro‐opiomelanocortin converting enzyme A possible mechanism for tissue‐specific processing

FEBS Letters

Bennett, Hugh P.J.¹  Birch, Nigel P.²  Estivariz, Fernando E.²  Lob, Y.Peng² 

[1] Royal Victoria Hospital, Montreal, Quebec H3A 1A1, Canada;Section on Cellular Neurobiology, Laboratory of Developmental Neurobiology, National Institute of Child Health and Human Development, Bldg 36, Rm 2A21, National Institutes of Health, Bethesda, MD 20892 USA

关键词: Neuropeptide;    Maturation;    Pro-opiomelanocortin processing;    O-Linked glycosylation;    POMC;    pro-opiomelanocortin;    ACTH;    adrenocorticotropin;    MSH;    melanocyte stimulating hormone;    CLIP;    corticotropinlike intermediate peptide;    LPH;    lipotropin;    b;    bovine;    HPLC;    high-performance liquid chromatography;   

DOI  :  10.1016/0014-5793(91)81257-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The amino terminus of bovine pro-opiomelanocortin (N-POMC^1–77) is partially processed in the intermediate lobe of the pituitary to N-POMC^1–49 and lys-γ₃ -melanotropin. Two pools of N-POMC^1–77 were isolated which were differentially glycosylated at threonine⁴⁵, while N-POMC^1–49 isolated from bovine intermediate lobe extracts existed in a non-glycosylated form. This suggested that differential O-linked glycosylation of N-POMC^1–77 may regulate cleavage at the Arg⁴⁹-Lys⁵⁰ processing site. We tested this hypothesis by incubating N-POMC^1–77 glycoforms with purified pro-opiomelanocortin converting enzyme. Only non-O-glycosylated N-POMC^1–77 and O-glycosylated N-POMC^1–77 with truncated oligosaccharide sidechains were sensitive to cleavage and generated predominantly lys-γ₃ -melanotropin, identified by high-performance liquid chromatography. These data provide the first functional evidence to support a role for differential O-linked glycosylation in the regulation of the processing of the N-terminus of bovine POMC.

【 授权许可】

Unknown