Project Grant F32GM167237

INVESTIGATING EPIGENETIC MECHANISMS OF ADAPTATION IN A POLYEXTREMOTOLERANT FUNGUS - PROJECT SUMMARY BACKGROUND: THE CAPACITY OF PATHOGENIC FUNGI TO ADAPT TO ANTIFUNGAL DRUGS REPRESENTS A CRITICAL AND INCREASING THREAT TO PUBLIC HEALTH. FUNGAL ADAPTATION HAS BEEN STUDIED EXTENSIVELY IN MODEL YEASTS, WHICH WHILE INFORMATIVE DOES NOT REPRESENT THE COMPLETE RANGE OF ADAPTIVE RESPONSES WITHIN THE FUNGAL KINGDOM. THIS PROPOSAL WILL LEVERAGE THE NON-MODEL, POLYEXTREMOTOLERANT YEAST-LIKE FUNGUS AUREOBASIDIUM PULLULANS TO INVESTIGATE MECHANISMS OF FUNGAL ADAPTATION. A GENERALIST ORGANISM, A. PULLULANS FACES ENVIRONMENTAL EXTREMES IN PH, SALT, AND TEMPERATURE. A. PULLULANS ALSO EXHIBITS A RANGE OF MORPHOLOGIES, SUCH AS SINGLE- BUDDED, MULTI-BUDDED, AND HYPHAL CELLS. ULTIMATELY, IDENTIFYING MOLECULAR MECHANISMS OF ADAPTATION IN NON- MODEL ORGANISMS MAY REVEAL PREVIOUSLY UNKNOWN PATHWAYS OF STRESS-INDUCED ADAPTATION. LONG TERM OBJECTIVES: EPIGENETIC CHANGES HAVE BEEN SHOWN TO BE A FAVORABLE MECHANISM OF FLEXIBLE ADAPTION IN DYNAMIC ENVIRONMENTS IN MODEL YEAST. THIS RESEARCH TRAINING PROJECT AIMS TO UNCOVER EPIGENETIC MECHANISMS OF ADAPTATION, LEVERAGING THE POLYEXTREMOTOLERANT FUNGUS, A. PULLULANS. THIS PROPOSAL WILL TEST THE PRIMARY HYPOTHESIS THAT A. PULLULANS USES STRESS-INDUCED EPIGENETIC CHANGES TO EXPLORE NEW CELL STATES AND ADAPT IN FLUCTUATING AND EXTREME CONDITIONS. TO TEST THIS, THIS PROPOSAL AIMS TO 1) CHARACTERIZE THE EPIGENETIC LANDSCAPE OF A. PULLULANS, 2) CHARACTERIZE THE DYNAMICS AND MECHANISMS OF A. PULLULANS ADAPTATION USING LAB- BASED EVOLUTION EXPERIMENTS AND FUNCTIONAL GENOMIC SCREENING, AND 3) INVESTIGATE MOLECULAR BET-HEDGING STRATEGIES USED BY A. PULLULANS TO ADAPT TO FLUCTUATING STRESS USING MOLECULAR GENETICS AND IMAGING ASSAYS. ULTIMATELY, THESE STUDIES WILL DEFINE MECHANISMS OF POLYEXTREMOTOLERANT ADAPTATION, INFORMING FUTURE WORK IN A. PULLULANS AND IN STRESS-INDUCED ADAPTATION OF OTHER ORGANISMS. TRAINING GOALS AND ENVIRONMENT: THE LONG-TERM GOAL OF THIS APPLICANT IS TO BECOME AN INDEPENDENT INVESTIGATOR AT AN ACADEMIC INSTITUTION, WHERE THEY WILL RUN A RESEARCH PROGRAM, MENTOR TRAINEES, AND TEACH STUDENTS. TO ACCOMPLISH THIS LONG-TERM GOAL, THE RESEARCH TRAINING PLAN IDENTIFIES TECHNICAL AND PROFESSIONAL AREAS TO DEVELOP DURING POSTDOCTORAL TRAINING PERIOD. THIS RESEARCH TRAINING PLAN IS A SIGNIFICANT PIVOT FROM THE APPLICANT'S PRIOR WORK STUDYING PLANT EPIGENETICS AND IS AN EXCELLENT OPPORTUNITY TO LEARN A NEW MODEL SYSTEM AND TECHNICAL SKILLS APPLICABLE TO FUTURE WORK. THE APPLICANT'S RESEARCH PLAN AND LONG-TERM GOALS ARE SUPPORTED BY PRIMARY MENTOR DR. KAUSHIK RAGUNATHAN (BRANDEIS UNIVERSITY) AND CO-MENTOR DR. DANIEL LEW (MIT). BOTH MENTORS BRING RELEVANT EXPERTISE TO THE PROJECT, DR. LEW IN THE CELL BIOLOGY OF A. PULLULANS AND DR. RAGUNATHAN STUDYING EPIGENETICS IN YEAST. THIS PROJECT WILL TAKE PLACE IN A HIGHLY COLLABORATIVE COMMUNITY OF RESEARCHERS WORKING IN A. PULLULANS, ENHANCING THE TRAINING AND RESEARCH POTENTIAL OF THIS PROJECT.