Similar subunit interactions contribute to assembly of clathrin adaptor complexes and COPI complex: analysis using yeast three-hybrid system.
Clathrin adaptor protein (AP) complexes are heterotetramers composed of two large, one medium, and one small subunits. By exploiting the yeast three-hybrid system, we have found that an interaction between the two large subunits of the AP-1 complex, gamma-adaptin and beta1-adaptin, is markedly enhanced in the presence of the small subunit, sigma1. Similarly, two large subunits of the AP-4 complex, epsilon-adaptin and beta4-adaptin, are found to interact with each other only in the presence of the small subunit, sigma4. Furthermore, we have found that an interaction between two large subunits of the COPI F subcomplex, gamma-COP and beta-COP, is detectable only in the presence of zeta-COP. Because these COPI subunits have common ancestral origins to the corresponding AP subunits, these three-hybrid data, taken together with the previous two-hybrid data, suggest that the AP complexes and the COPI F subcomplex assemble by virtue of similar subunit interactions.
Takatsu
H
H
Institute of Biological Sciences and Gene Experiment Center, University of Tsukuba, Ibaraki, Tsukuba Science City, 305-8572, Japan.
Futatsumori
M
M
Yoshino
K
K
Yoshida
Y
Y
Shin
H W
HW
Nakayama
K
K
D033961:Adaptor Protein Complex 1; D033962:Adaptor Protein Complex 2; D034002:Adaptor Protein Complex sigma Subunits; D033942:Adaptor Proteins, Vesicular Transport; D002966:Clathrin / Q000378:metabolism; D003001:Cloning, Molecular; D020755:Coat Protein Complex I / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D008099:Liver / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D010750:Phosphoproteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
C438983:AP1S1 protein, human; C510065:AP2S1 protein, human; C499068:APS1 protein, S cerevisiae; D033961:Adaptor Protein Complex 1; D033962:Adaptor Protein Complex 2; D034002:Adaptor Protein Complex sigma Subunits; D033942:Adaptor Proteins, Vesicular Transport; D002966:Clathrin; D020755:Coat Protein Complex I; D009419:Nerve Tissue Proteins; D010750:Phosphoproteins; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; C499071:adaptor protein complex 1, sigma 1 subunit; D001616:beta-Galactosidase