TY - JOUR
T1 - Role of Pex19p in the targeting of PMP70 to peroxisome
AU - Kashiwayama, Yoshinori
AU - Asahina, Kota
AU - Shibata, Hiroyuki
AU - Morita, Masashi
AU - Muntau, Ania C.
AU - Roscher, Adelbert A.
AU - Wanders, Ronald J.A.
AU - Shimozawa, Nobuyuki
AU - Sakaguchi, Masao
AU - Kato, Hiroaki
AU - Imanaka, Tsuneo
N1 - Funding Information:
This work was supported in part by a Grad-in Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan (10217205 and 14370740) and grants from The Hokuriku Industrial Advancement and The Fugaku Trust for Medical Research. We would like to thank San Francisco Edit ( www.sfedit.net ) for their assistance in editing the manuscript.
PY - 2005/12/15
Y1 - 2005/12/15
N2 - Pex19p is a protein required for the peroxisomal membrane synthesis. The 70-kDa peroxisomal membrane protein (PMP70) is synthesized on free cytosolic ribosomes and then inserted posttranslationally into peroxisomal membranes. Pex19p has been shown to play an important role in this process. Using an in vitro translation system, we investigated the role of Pex19p as a chaperone and identified the regions of PMP70 required for the interaction with Pex19p. When PMP70 was translated in the presence of purified Pex19p, a large part of PMP70 existed as soluble form and was co-immunoprecipitated with Pex19p. However, in the absence of Pex19p, PMP70 formed aggregates during translation. To identify the regions that interact with Pex19p, various truncated PMP70 were translated in the presence of Pex19p and subjected to co-immunoprecipitation. The interaction was markedly reduced by the deletion of the NH2-terminal 61 amino acids or the region around TMD6. Further, we expressed these deletion constructs of PMP70 in fusion with the green fluorescent protein in CHO cells. Fusion proteins lacking these Pex19p binding sites did not display any peroxisomal localization. These results suggest that Pex19p binds to PMP70 co-translationally and keeps PMP70 as a proper conformation for the localization to peroxisome.
AB - Pex19p is a protein required for the peroxisomal membrane synthesis. The 70-kDa peroxisomal membrane protein (PMP70) is synthesized on free cytosolic ribosomes and then inserted posttranslationally into peroxisomal membranes. Pex19p has been shown to play an important role in this process. Using an in vitro translation system, we investigated the role of Pex19p as a chaperone and identified the regions of PMP70 required for the interaction with Pex19p. When PMP70 was translated in the presence of purified Pex19p, a large part of PMP70 existed as soluble form and was co-immunoprecipitated with Pex19p. However, in the absence of Pex19p, PMP70 formed aggregates during translation. To identify the regions that interact with Pex19p, various truncated PMP70 were translated in the presence of Pex19p and subjected to co-immunoprecipitation. The interaction was markedly reduced by the deletion of the NH2-terminal 61 amino acids or the region around TMD6. Further, we expressed these deletion constructs of PMP70 in fusion with the green fluorescent protein in CHO cells. Fusion proteins lacking these Pex19p binding sites did not display any peroxisomal localization. These results suggest that Pex19p binds to PMP70 co-translationally and keeps PMP70 as a proper conformation for the localization to peroxisome.
KW - ABC protein
KW - PMP70
KW - Peroxisome
KW - Peroxisome membrane protein
KW - Pex19p
UR - http://www.scopus.com/inward/record.url?scp=28844440461&partnerID=8YFLogxK
U2 - 10.1016/j.bbamcr.2005.10.006
DO - 10.1016/j.bbamcr.2005.10.006
M3 - 学術論文
C2 - 16344115
AN - SCOPUS:28844440461
SN - 0167-4889
VL - 1746
SP - 116
EP - 128
JO - BBA - Molecular Cell Research
JF - BBA - Molecular Cell Research
IS - 2
ER -