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Title: Gene Expression by a Model Fungus in the Ascomycota Provides Insight Into the Decay of Fungal Necromass
ABSTRACT Dead fungal cells, known as necromass, are increasingly recognised as significant contributors to long‐term soil carbon pools, yet the genes involved in necromass decomposition are poorly understood. In particular, how microorganisms degrade necromass with differing initial cell wall chemical compositions using carbohydrate‐active enzymes (CAZymes) has not been well studied. Based on the frequent occurrence and high abundance of the fungal genusTrichodermaon decaying fungal necromass in situ, we grewTrichoderma reeseiRUT‐C30 on low and high melanin necromass ofHyaloscypha bicolor(Ascomycota) in liquid cultures and assessedT. reeseigene expression relative to each other and relative to glucose. Transcriptome data revealed thatT. reeseiup‐regulated many genes (over 100; necromass versus glucose substrate) coding for CAZymes, including enzymes that would target individual layers of an Ascomycota fungal cell wall. We also observed differential expression of protease‐ and laccase‐encoding genes on high versus low melanin necromass, highlighting a subset of genes (fewer than 15) possibly linked to the deconstruction of melanin, a cell wall constituent that limits necromass decay rates in nature. Collectively, these results advance our understanding of the genomic traits underpinning the rates and fates of carbon turnover in an understudied pool of Earth's belowground carbon, fungal necromass.  more » « less
Award ID(s):
2038293
PAR ID:
10562551
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Environmental Microbiology
Volume:
26
Issue:
12
ISSN:
1462-2912
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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