Francis Crick Institute Ralser Lab - Kamrad_et_al_13Cproteomics_metabolic_heterogeneity

Differential isotope labelling by amino acids (DILAC) reveals metabolic cross-feeding and phenotypic heterogeneity in a clonal cell population
Data License: CC BY 4.0 | ProteomeXchange: PXD036959 | doi: https://doi.org/10.6069/s9b3-zz35
  • Organism: Saccharomyces cerevisiae
  • Instrument: TripleTOF 6600
  • SpikeIn: No
  • Keywords: 13C, yeast, heterogeneity, subpopulations, PRM, DILAC
  • Lab head: Markus Ralser Submitter: Stephan Kamrad
Abstract
Genetically identical cells are known to differ in many physiological parameters such as growth rate and drug tolerance, but the source of such heterogeneity is often insufficiently understood. Exchange interactions between metabolite producing and consuming cells are believed to be one possible cause, but detecting metabolically divergent subpopulations remains technically challenging. We developed a proteomics-based technology, termed differential isotope labelling by amino acids (DILAC), which monitors amino acid incorporation into peptides with multiple occurrences of the same amino acid. DILAC is used to differentiate producer and consumer cells of a particular amino acid within an isogenic cell population. We applied DILAC to young, morphologically undifferentiated yeast colonies and reveal that they contain sub-populations of lysine producers and consumers which emerge due to nutrient gradients. DILAC can deconvolute the proteome of subpopulations from bulk measurements which indicated an in situ cross feeding situation where fast growing cells ferment and provide the slower growing, respiring cells with ethanol as substrate. Finally, by combining DILAC with FACS, we show that the metabolic states that differ between isogenic cells, confer resistance to the antifungal drug amphotericin B. Overall, this novel and broadly applicable methodological approach captures previously unnoticed metabolic heterogeneity, providing experimental evidence for the role of metabolic specialisation and cross-feeding interactions as a source of phenotypic heterogeneity in isogenic cell populations.
Experiment Description
This submission contains several subfolders containing data from different experiments. Please see the overview below.
Created on 9/24/22, 3:26 PM

 

Subfolder: Dataset2_lysine_colony_timecourse_gluC

This folder contains data relating to Figure 2 and Extended View 2B+E

This folder contains two skyline files:

20210602_KgluC_labelMod_permut_2022-08-24_12-17-54.sky  -  Main experiment measuring labelling states of peptides containing 2 lysine residues in colonies grown on 13C glucose supplemented with 4 different lysine concentrations, over 3 timepoints, in 2 biological replicates.

20220906_KgluC_3lysine_2022-09-21_10-33-32.sky  -  Additional experiment shown in Extended View 2E where two samples from theabove experiment were remeasuredto look at peptides with three lysine residues.

Detailed description:

Yeast colonies were grown for 1,2 or 3 days on minimal media with 1% 13C glucose and various amounts of unlabelled lysine. Proteome samples from whole colonies were prepared by reduction-alkylation and digestion with gluC. The labelling state of a selected number of peptides containing two lysine residues was determined in 20210602_KgluC_labelMod_permut_2022-08-24_12-17-54.sky. This experiment contains data for 4 different lysine supplementation concentrations, 3 different timepoints and 2 biological replicates (one raw data file each, file name contains all relevant information). The two samples remeasured in 20220906_KgluC_3lysine.sky are the two biological replicates harvested at 48h supplemented with 200uM lysine. We additionally provide 28 raw data files, the skyline reports used for downstream analysis and Jupyter notebooks containing the code used to generate the figures in the publication.

 

 

Subfolder: ExtendedView_lysine_colony_timecourse_missedCleavage

This folder contains data relating to Extended View 2C

This folder contains one skyline file:

20210810_K_missedCleavage_2022-08-24_15-23-40.sky  -  Using missed cleavage peptides from tryptic digests (instead of gluC digests) to quantify producer/consumer labelling states.

Detailed description:

Yeast colonies were grown for up to 3 days on minimal media with 1% 13C glucose and various amounts of unlabelled lysine. Proteome samples from whole colonies were prepared by reduction-alkylation and digestion with trypsin. The labelling state of a selected number of peptides containing two lysine residues was determined (these were missed cleavage peptides). This folder contains one Skyline document and 24 raw data files, the skyline report used for downstream analysis. Note the unusual "minus0.001" modification applied to one of the mixed labelling state precursors and see the following Skyline forum support thread for more information: https://skyline.ms/announcements/home/support/thread.view?entityId=8ebed690-dbfa-1039-a3a0-e465a393713c&_docid=thread%3A8ebed690-dbfa-1039-a3a0-e465a393713c

This experiment contains data for 3 different lysine supplementation concentrations, 4 different timepoints and 2 biological replicates (one raw data file each, file name contains all relevant information).

 

Subfolder: ExtendedView_lysine_liquid_timecourse

This folder contains data relating to Extended View 1

This folder contains one skyline file:

20210923_K_missedCleavage_2022-08-24_12-59-30.sky   -   Investigation of lysine producer/consumer subpopulations in liquid yeast cultures using targeted 13C proteomics 

Detailed description:

Liquid batch cultures of yeast were grown in minimal media containing 1% 13C glucose and 68mM lysine. Proteome samples were prepared by reduction-alkylation and digestion with trypsin. The labelling state of a selected number of peptides containing two lysine residues (missed cleavage peptides) was determined. This folder contains one Skyline document, 18 raw data files, a metadata table in csv format, the skyline report used for downstream analysis. This experiment contains 4 biological replicates. Cultures were samples at four different timepoints, few hours apart. Samples are numbered 1-16, the corresponding metadata can be found in the csv table included with the raw data files. Note the unusual "minus0.001" modification applied to one of the mixed labelling state precursors and see the following Skyline forum support thread for more information: https://skyline.ms/announcements/home/support/thread.view?entityId=8ebed690-dbfa-1039-a3a0-e465a393713c&_docid=thread%3A8ebed690-dbfa-1039-a3a0-e465a393713c

Subfolder: ExtendedView_otherAA_colony_timecourse

This folder contains data relating to Extended View 3

This folder contains three skyline files:

20220826_L_2022-08-26_16-07-34.sky   -   Investigation of producer/consumer subpopulations in yeast colonies supplemented with leucine
20220824_F_2022-08-26_16-01-27.sky   -   Investigation of producer/consumer subpopulations in yeast colonies supplemented with phenylalanine
20220825_N_2022-08-26_12-34-34.sky    -    Investigation of producer/consumer subpopulations in yeast colonies supplemented with asparagine

Detailed description:

Yeast colonies were grown for 1,2 or 3 days on minimal media with 1% 13C glucose and various amounts of three different amino acids (leucine, asparagine, phenylalanine). Proteome samples from whole colonies were prepared by reduction-alkylation and digestion with trypsin. The labelling state of a selected number of peptides containing two residues of the supplemented amino acid was determined. This folder contains three Skyline document, raw data files, the skyline reports used for downstream analysis and a Jupyter notebook containing the code used to generate the figures in the publication. This experiment contains data for 3 different amino acids, 3 different timepoints, 3 different concentrations, each in biological duplicates (one raw data file each, file name contains all relevant information). Note the unusual "minus0.001" modification applied to one of the mixed labelling state precursors and see the following Skyline forum support thread for more information: https://skyline.ms/announcements/home/support/thread.view?entityId=8ebed690-dbfa-1039-a3a0-e465a393713c&_docid=thread%3A8ebed690-dbfa-1039-a3a0-e465a393713c