Functional analysis of a Hansenula polymorpha MNN2-2 homologue encoding a putative UDP-N-acetylglucosamine transporter localized in the endoplasmic reticulum.
The Kluyveromyces lactis UDP-GlcNAc transporter (KlMnn2-2p) is responsible for the biosynthesis of N-glycans containing N-acetylglucosamine. A putative gene of Hansenula polymorpha encoding a KlMnn2-2p homologue, HpMNN2-2, was identified and investigated for its function. The deletion mutant strain of HpMNN2-2 (Hpmnn2-2Δ) showed increased sensitivity to geneticin, hygromycin B, and tunicamycin. However, the Hpmnn2-2Δ strain exhibited increased resistance to Calcofluor white, an inhibitor of chitin biosynthesis, along with a reduced chitin content. The localization of HpMnn2-2p at the endoplasmic reticulum-enriched membrane, different from the Golgi localization of a K. lactis homologue, further supports the involvement of HpMnn2-2p in cell wall chitin biosynthesis.
Department of Life Science, Research Center for Biomolecules and Biosystems, Chung-Ang University, Seoul 156-756, Republic of Korea.
Jeong-Nam
JN
Park
Jinho
J
Choo
Hyun Ah
HA
Kang
D000595:Amino Acid Sequence; D004721:Endoplasmic Reticulum / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D007716:Kluyveromyces / Q000235:genetics; D026901:Membrane Transport Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010843:Pichia / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D016415:Sequence Alignment
D005656:Fungal Proteins; D026901:Membrane Transport Proteins; C121945:UDP-N-acetylglucosamine transporter