Nuclear translocation of the heterotrimeric CCAAT binding factor of Aspergillus oryzae is dependent on two redundant localising signals in a single subunit.
The CCAAT-binding complex in the Aspergillus species, also known as the Hap complex, consists of at least three subunits, namely HapB, HapC and HapE. Each Hap subunit contains an evolutionary conserved core domain. Recently, we have found that the HapC and HapE subunits do not carry a nuclear localisation signal. Furthermore, when in complex with HapB, they are transported into the nucleus via a 'piggy back mechanism' in A. nidulans. To extend our findings to other filamentous fungi, we examined the nuclear localisation of the A. oryzae Hap subunits by analysing several GFP fusion proteins with these Hap subunits in the hap deletion strains of A. nidulans. The nuclear translocation of the A. oryzae complex was found to be dependent on two redundant localising signals in HapB.
Goda
Hideya
H
Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan.
Nagase
Takashi
T
Tanoue
Shinjiro
S
Sugiyama
Junya
J
Steidl
Stefan
S
Tüncher
André
A
Kobayashi
Tetsuo
T
Tsukagoshi
Norihiro
N
Brakhage
Axel A
AA
Kato
Masashi
M
D000595:Amino Acid Sequence; D001236:Aspergillus oryzae / Q000235:genetics / Q000378:metabolism*; D023081:CCAAT-Binding Factor / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D019913:Nuclear Localization Signals / Q000502:physiology*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000378:metabolism
D023081:CCAAT-Binding Factor; D005656:Fungal Proteins; D019913:Nuclear Localization Signals; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins