Vesicle-trafficking mutants’ effects on spo7ts nuclear shape and spo7 viability
| Group | Gene deleted | Percentagea of multi-flared nuclei when combined with spo7ts | Statistical significanceb (P < 0.003) | Genetic interactionc with spo7 | Protein functiond |
| A | ARL1 | 33 ± 5.7 | Yes | ++++ | Soluble GTPase with a role in regulation of membrane traffic |
| A | SYS1 | 34.5 ± 4.9 | Yes | ++++ | Integral membrane protein of the Golgi required for targeting Arl3p to the Golgi |
| B | ARL3 | 30.0 ± 4.2 | Yes | ++++ | GTPase required to recruit Arl1p to the Golgi |
| B | RIC1 | 18.5 ± 2.1 | Yes | ++++ | Forms heterodimer with Rgp1p that acts as a GTP exchange factor for Ypt6p |
| B | YPT6 | 26.5 ± 4.9 | Yes | ++++ | GTPase required for fusion of endosome-derived vesicles with the late Golgi |
| C | ERV14 | 37.5 ± 2.1 | Yes | ++++ | Protein localized to COPII-coated vesicles, involved in vesicle formation and incorporation of specific secretory cargo |
| C | COG8 | 22.5 ± 4.9 | Yes | +++ | Component of the conserved oligomeric Golgi complex that functions in fusion of transport vesicles to Golgi compartments |
| C | VPS52 | 9.5 ± 4.9 | No | ++ | Component of the GARP complex required for the recycling of proteins from endosomes to the late Golgi |
| C | TLG2 | 4.5 ± 0.7 | No | ++ | t-SNARE that mediates fusion of endosome-derived vesicles with the late Golgi |
| C | SWA2 | 8.0 ± 2.8 | No | + | Clathrin-binding protein required for uncoating of clathrin-coated vesicles |
| C | APL5 | 6.5 ± 0.7 | No | + | Delta adaptin-like subunit of the clathrin associated protein complex (AP-3) involved in transport to the vacuole |
| C | GYP1 | 1.0 ± 1.4 | No | − | Cis-golgi GTPase-activating protein (GAP) for Ypt1p, involved in vesicle docking and fusion |
| D | ARF1 | 23.0 ± 4.2 | Yes | ++ | GTPase involved in regulation of coated vesicle formation in intracellular trafficking within the Golgi |
| D | VPS35 | 2.0 ± 1.4 | No | ++ | Endosomal subunit of membrane-associated retromer complex required for retrograde transport |
| D | VPS41 | 1.5 ± 0.7 | No | ++ | Vacuolar membrane protein, subunit of the homotypic vacuole fusion and vacuole protein sorting (HOPS) complex |
| D | GCS1 | 2.0 ± 0.0 | No | + | ARF GAP involved in ER-Golgi transport |
| D | GET2 | 6.0 ± 5.7 | No | + | Subunit of the GET complex; involved in insertion of proteins into the ER membrane |
| D | VPS25 | 2.5 ± 2.1 | No | + | Component of the ESCRT-II complex; involved in ubiquitin-dependent sorting of proteins into the endosome |
| Group | Gene deleted | Percentagea of multi-flared nuclei when combined with spo7ts | Statistical significanceb (P < 0.003) | Genetic interactionc with spo7 | Protein functiond |
| A | ARL1 | 33 ± 5.7 | Yes | ++++ | Soluble GTPase with a role in regulation of membrane traffic |
| A | SYS1 | 34.5 ± 4.9 | Yes | ++++ | Integral membrane protein of the Golgi required for targeting Arl3p to the Golgi |
| B | ARL3 | 30.0 ± 4.2 | Yes | ++++ | GTPase required to recruit Arl1p to the Golgi |
| B | RIC1 | 18.5 ± 2.1 | Yes | ++++ | Forms heterodimer with Rgp1p that acts as a GTP exchange factor for Ypt6p |
| B | YPT6 | 26.5 ± 4.9 | Yes | ++++ | GTPase required for fusion of endosome-derived vesicles with the late Golgi |
| C | ERV14 | 37.5 ± 2.1 | Yes | ++++ | Protein localized to COPII-coated vesicles, involved in vesicle formation and incorporation of specific secretory cargo |
| C | COG8 | 22.5 ± 4.9 | Yes | +++ | Component of the conserved oligomeric Golgi complex that functions in fusion of transport vesicles to Golgi compartments |
| C | VPS52 | 9.5 ± 4.9 | No | ++ | Component of the GARP complex required for the recycling of proteins from endosomes to the late Golgi |
| C | TLG2 | 4.5 ± 0.7 | No | ++ | t-SNARE that mediates fusion of endosome-derived vesicles with the late Golgi |
| C | SWA2 | 8.0 ± 2.8 | No | + | Clathrin-binding protein required for uncoating of clathrin-coated vesicles |
| C | APL5 | 6.5 ± 0.7 | No | + | Delta adaptin-like subunit of the clathrin associated protein complex (AP-3) involved in transport to the vacuole |
| C | GYP1 | 1.0 ± 1.4 | No | − | Cis-golgi GTPase-activating protein (GAP) for Ypt1p, involved in vesicle docking and fusion |
| D | ARF1 | 23.0 ± 4.2 | Yes | ++ | GTPase involved in regulation of coated vesicle formation in intracellular trafficking within the Golgi |
| D | VPS35 | 2.0 ± 1.4 | No | ++ | Endosomal subunit of membrane-associated retromer complex required for retrograde transport |
| D | VPS41 | 1.5 ± 0.7 | No | ++ | Vacuolar membrane protein, subunit of the homotypic vacuole fusion and vacuole protein sorting (HOPS) complex |
| D | GCS1 | 2.0 ± 0.0 | No | + | ARF GAP involved in ER-Golgi transport |
| D | GET2 | 6.0 ± 5.7 | No | + | Subunit of the GET complex; involved in insertion of proteins into the ER membrane |
| D | VPS25 | 2.5 ± 2.1 | No | + | Component of the ESCRT-II complex; involved in ubiquitin-dependent sorting of proteins into the endosome |
Average frequency ± SD of multi-flared nuclei in cells grown at 37°C for 3 h. n = 200 for each strain.
Statistical significance of the multi-flared nuclear phenotype, as calculated by Fisher’s exact test with Bonferroni correction. Values from each deleted gene with spo7ts are compared to the frequency of multi-flared nuclei in spo7ts alone (2 ± 2.8).
The strength of the genetic interaction between spo7Δ and each mutation was assessed by the spot assay (Fig. S1), ranging from synthetic lethality (++++) to no interaction (−).
Description of protein function obtained from Saccharomyces Genome Database (http://www.yeastgenome.org/).