SNARE chaperone Sly1 directly mediates close-range vesicle tethering

The essential Golgi protein Sly1 is a member of the SM (Sec1/mammalian Unc-18) family of SNARE chaperones. Sly1 was originally identified through remarkable gain-of-function alleles that bypass requirements for diverse vesicle tethering factors. Employing genetic analyses and chemically defined reconstitutions of ER-Golgi fusion, we discovered that a loop conserved among Sly1 family members is not only autoinhibitory, but also acts as a positive effector. An ALPS (amphipathic lipid packing sensors)-like amphipathic helix within the loop directly binds high-curvature membranes. Membrane binding is required for relief of Sly1 autoinhibition and also allows Sly1 to directly tether incoming vesicles to the Qa-SNARE on the target organelle. The SLY1-20 mutation bypasses requirements for diverse tethering factors but loses this ability if the tethering activity is impaired. We propose that long-range tethers, including Golgins and multisubunit tethering complexes, hand off vesicles to Sly1, w..., SGA analysis
A query strain (AMY2443) was constructed in the Y9205 genetic background (Tong and Boone, 2005), with sly1∆loop and a linked nourseothricin (NAT) marker integrated through allelic replacement at the native SLY1 locus. This query strain was crossed to the MAT a haploid deletion and DAmP libraries, where each individual genetic perturbation is marked with a KAN resistance marker (Breslow et al., 2008; Tong and Boone, 2005). Diploids were selected by robotic pinning (Singer RoToR) onto YPD + 100 mg/L clonNAT + 200 mg/L G418, then induced to sporulate by pinning to sporulation medium (20g/L agar, 10g/L potassium acetate, 1g/L yeast extract, 0.5g/L glucose, 0.1g/L amino acid supplement [2g histidine, 10g leucine, 2g lysine, 2g uracil]) and growth at room temperature for 5 days. Spores were subsequently pinned to haploid selection medium (SD -His/Arg/Lys + 50 mg/L canavanine + 50 mg/L thialysine) and MAT a meiotic progeny grown for 2 days at 25º C. This haploid selection step was..., , # Yeast Sly1 SGA, BioGrid, and Gene Ontology Supplemental Dataset

## Description of the data and file structure:

To gain genome-scale insight into the *sly1∆loop* allele’s loss of function, we used synthetic genome array (SGA) analysis. SGA measures the synthetic sickness or rescue (suppression) of a query allele versus a genome-scale collection of loss-of-function alleles (Tong and Boone, 2005). The *sly1∆loop* allele was knocked into the genomic *SLY1* locus. The SGA data from this analysis was then aligned with the BioGRID dataset.

## **Contents of the dataset:**

***sly1∆loop SGA*** contains the raw SGA dataset. The SGA score algorithm processes raw colony size data, normalizes them for a series of experimental systematic effects and calculates a quantitative genetic interaction score.

**LogRatios** indicates the log-transformed ratio of the growth of the indicated double mutant to the growth of the single mutant with the indicated query allele.

**ZScores** is a unitless indi...