Disulfide‐bonding between Drosophila laminin β and γ chains is essential for α chain to form αβγ trimer

FEBS Letters

Kadowaki, Tatsuhiko²  Kitagawa, Yasuo¹  Kumagai, Chino¹ 

[1] Graduate Program for Biochemical Regulation, Graduate School of Agricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-01, Japan;Nagoya University BioScience Center, Chikusa, Nagoya 464-01, Japan

关键词: Basement membrane;    Disulfide-bonding;    Drosophila;    Laminin;    CBB;    Coomassie brilliant blue;    ECL;    enhanced chemiluminescence;    EGF;    epidermal growth factor;    EHS;    Engelbreth-Holm-Swarm;    NEM;    N-ethylmaleimide;    PBS;    phosphate-buffered saline;    RIPA;    radio-immunoprecipitation assay;    PMSF;    phenylmethylsulfonylfluoride;    SDS;    sodium dodecylsulfate;   

DOI  :  10.1016/S0014-5793(97)00780-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Assembly of Drosophila laminin α, β and γ chains was analyzed by immunoprecipitation of the lysate from metabolically radiolabeled Kc 167 cells with chain-specific antibodies followed by two dimensional electrophoresis in which non-reducing and reducing SDS gel electrophoresis are combined. Precipitation of monomeric β (or γ) with anti-γ (or -β) antibody revealed that β and γ form stable dimer before they are disulfide-bonded to each other. In contrast, α associates with neither monomeric β, monomeric γ nor βγ dimer without disulfide-bonding but only with disulfide-bonded βγ dimer to form αβγ trimers. These results thus demonstrated that the interchain disulfide-boding between β and γ is essential for α to form αβγ trimer. We also found that the αβγ trimer can be secreted with α chain either disulfide-bonded or not bonded to the disulfide-bonded βγ dimer.

【 授权许可】

Unknown