biostudies-literatureTill PAustrian Science Fund FWF47-61https://www.ebi.ac.uk/biostudies/studies/S-EPMC6948969biostudies-literatureUnknown17(1)Long non-coding RNAs (lncRNAs) are crucial factors acting on regulatory processes in eukaryotes. Recently, for the first time in a filamentous fungus, the lncRNA <i>HAX1</i> was characterized in the ascomycete <i>Trichoderma reesei</i>. In industry, this fungus is widely applied for the high-yield production of cellulases. The lncRNA <i>HAX1</i> was reported to influence the expression of cellulase-encoding genes; interestingly, this effect is dependent on the presence of its most abundant length. Clearly, <i>HAX1</i> acts in association with a set of well-described transcription factors to regulate gene expression. In this study, we attempted to elucidate the regulatory strategy of <i>HAX1</i> and its interactions with the major transcriptional activator Xylanase regulator 1 (Xyr1). We deRNA biologyRegulation of gene expression by the action of a fungal lncRNA on a transactivator.PMC6948969P 26618Yaver DTill PMach-Aigner ARMach RLDerntl CKiesenhofer DPfalseRegulation of gene expression by the action of a fungal lncRNA on a transactivator.Long non-coding RNAs (lncRNAs) are crucial factors acting on regulatory processes in eukaryotes. Recently, for the first time in a filamentous fungus, the lncRNA <i>HAX1</i> was characterized in the ascomycete <i>Trichoderma reesei</i>. In industry, this fungus is widely applied for the high-yield production of cellulases. The lncRNA <i>HAX1</i> was reported to influence the expression of cellulase-encoding genes; interestingly, this effect is dependent on the presence of its most abundant length. Clearly, <i>HAX1</i> acts in association with a set of well-described transcription factors to regulate gene expression. In this study, we attempted to elucidate the regulatory strategy of <i>HAX1</i> and its interactions with the major transcriptional activator Xylanase regulator 1 (Xyr1). We de2020-01-01T00:00:00Z2020 Jan2025-04-04T20:45:03.387Z2020-05-22T07:45:00ZS-EPMC69489693151756410.1080/15476286.2019.1663618