Disease relevance of BFR1

• The bfr1+ gene is not essential for cell growth or mating, but a delta bfr1 mutant exhibited hypersensitivity to BFA [1].

High impact information on BFR1

• Tetraploid yeast cells lacking BFR1 or overexpressing an essential gene BBP1 produce a novel type of ascus that contains asci instead of spores [2].
• Bfr1p and Bbp1p interact with each other in a two hybrid assay, further suggesting that they might form a complex important for cell cycle coordination [2].
• Cells depleted of Bbp1p or lacking Bfr1p are defective in a number of processes such as nuclear segregation, bud formation, cytokinesis and nuclear spindle formation [2].
• BFR1, a multicopy suppressor of brefeldin A-induced lethality, is implicated in secretion and nuclear segregation in Saccharomyces cerevisiae [3].
• A bfr1-delta 1::URA3 deletion strain is viable, but has defects in cell morphology and nuclear segregation, and the mutation accentuates the growth and secretion defects of a sec21 mutant [3].

Biological context of BFR1

• The presence of Bfr1p is intriguing because the null phenotype for this gene is essentially the same as that reported for scp160 -null cells: increased cell size and aberrant DNA content [4].
• Using affinity-chromatography to isolate these complexes, we have identified two protein components other than Scp160p: poly(A) binding protein, Pab1p, and Bfr1p [4].
• This structural characteristic of bfr1+ protein resembles that of mammalian P-glycoprotein, which, by exporting a variety of anticancer drugs, has been shown to be responsible for multidrug resistance in tumor cells [1].

Anatomical context of BFR1

• Finally, we report that loss of Bfr1p disrupts the interaction of Scp160p with polyribosomes, thereby demonstrating that the relationship between these two proteins is functional as well as physical [5].
• Furthermore, we have determined by fluorescence microscopy and subcellular fractionation that Bfr1p and Scp160p demonstrate similar cytoplasmic localization with enrichment around the nuclear envelope/endoplasmic reticulum [5].

References