Caenorhabditis elegans ortholog of the p24/p22 subunit, DNC-3, is essential for the formation of the dynactin complex by bridging DNC-1/p150(Glued) and DNC-2/dynamitin.
Dynactin is a multisubunit protein complex required for the activity of cytoplasmic dynein. In Caenorhabditis elegans, although 10 of the 11 dynactin subunits were identified based on the sequence similarities to their orthologs, the p24/p22 subunit has not been detected in the genome. Here, we demonstrate that DNC-3 (W10G11.20) is the functional counterpart of the p24/p22 subunit in C. elegans. RNAi phenotypes and subcellular localization of DNC-3 in early C. elegans embryos were nearly identical to those of the known dynactin components. All other dynactin subunits were co-immunoprecipitated with DNC-3, indicating that DNC-3 is a core component of dynactin. Furthermore, the overall secondary structure of DNC-3 resembles to those of the mammalian and yeast p24/p22. We found that DNC-3 is required for the localization of the DNC-1/p150(Glued) and DNC-2/dynamitin, the two components of the projection arm of dynactin, to the nuclear envelope of meiotic nuclei in the adult gonad. Moreover, DNC-3 physically interacted with DNC-1 and DNC-2 and significantly enhanced the binding ability between DNC-1 and DNC-2 in vitro. These results suggest that DNC-3 is essential for the formation of the projection arm subcomplex of dynactin.
Laboratory for Developmental Genomics, RIKEN Center for Developmental Biology, Kobe, Hyogo, Japan.
Masahiro
M
Terasawa
Mika
M
Toya
Fumio
F
Motegi
Miyeko
M
Mana
Kuniaki
K
Nakamura
Asako
A
Sugimoto
D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D056445:Cytoplasmic Dyneins / Q000378:metabolism; D000072159:Dynactin Complex; D004625:Embryo, Nonmammalian; D005982:Glutathione Transferase / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D017433:Protein Structure, Secondary / Q000235:genetics; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism*; D034622:RNA Interference; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D013347:Subcellular Fractions / Q000378:metabolism
D000072159:Dynactin Complex; D008869:Microtubule-Associated Proteins; C000606366:NIP100 protein, S cerevisiae; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D005982:Glutathione Transferase; D056445:Cytoplasmic Dyneins