High impact information on SBE2

• Sbe2p and sbe22p, two homologous Golgi proteins involved in yeast cell wall formation [1].
• We have identified and characterized two homologous yeast proteins, Sbe2p and Sbe22p, through their suppression of a chs5 spa2 mutant strain defective in chitin synthesis and cell morphogenesis [1].
• Finally, immunofluorescence experiments reveal that in small-budded cells, sbe2 sbe22 mutants mislocalize Chs3p, a protein involved in chitin synthesis [1].
• Second, electron microscopic analysis reveals that sbe2 sbe22 cells have an aberrant cell wall structure with a reduced mannoprotein layer [1].
• In addition, sbe2 sbe22 diploids have a bud-site selection defect, displaying a random budding pattern [1].

Biological context of SBE2

• The SBE2 cDNA plasmid conferred again galactose-dependent caspofungin resistance when transformed back into the wild-type S. cerevisiae [2].
• Although sbe2 and sbe22 null mutants are viable, sbe2 sbe22 cells display several phenotypes indicative of defects in cell integrity and cell wall structure [1].

Anatomical context of SBE2

• SBE2 has been described in S. cerevisiae to encode a Golgi protein involved in the transport of cell wall components (B. Santos and M. Snyder, Mol. Biol. Cell, 11:435-452, 2000) [2].
• Thus, we suggest a model in which Sbe2p and Sbe22p are involved in the transport of cell wall components from the Golgi apparatus to the cell surface periphery in a pathway independent of Chs5p [1].

Regulatory relationships of SBE2

• In conclusion, overexpression of Sbe2p under the regulated control of the GAL1 promoter results in caspofungin resistance in S. cerevisiae [2].

References