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Wood-decaying fungi of the class Agaricomycetes (phylum Basidiomycota) are saprotrophs that break down lignocellulose and play an important role in nutrient recycling. They secrete a wide range of extracellular plant cell wall degrading enzymes that break down cellulose, hemicellulose, and lignin, the main building blocks of plant biomass. Although the production of these enzymes is regulated mainly at the transcriptional level, no activating regulators have been identified in any wood-decaying fungus in the class Agaricomycetes. We studied the regulation of cellulase expression in the wood-decaying fungus Schizophyllum commune. Comparative genomics and transcriptomics on two wild isolates revealed a Zn2Cys6-type transcription factor gene (roc1) that was highly upregulated during growth on cellulose, compared to glucose. It is only conserved in the class Agaricomycetes. A roc1 knockout strain showed an inability to grow on medium with cellulose as sole carbon source, and growth on cellobiose and xylan (other components of wood) was inhibited. Growth on non-wood-related carbon sources was not inhibited. Cellulase gene expression and enzyme activity were reduced in the Δroc1 strain. ChIP-Seq identified 1474 binding sites of the Roc1 transcription factor. Promoters of genes involved in lignocellulose degradation were enriched with these binding sites, especially those of LPMO (lytic polysaccharide monooxygenase) CAZymes, indicating that Roc1 directly regulates these genes. A conserved motif was identified as the binding site of Roc1, which was confirmed by a functional promoter analysis. Together, Roc1 is a key regulator of cellulose degradation and the first identified in wood-decaying fungi in the phylum Basidiomycota. IMPORTANCE Wood-degrading fungi in the phylum Basidiomycota play a crucial role in nutrient recycling by breaking down all components of wood. Fungi have evolved transcriptional networks that regulate expression of wood-degrading enzymes, allowing them to prioritize one nutrient source over another. However, to date all these transcription factors have been identified in the phylum Ascomycota, which is only distantly related to the phylum Basidiomycota. Here, we identified the transcription factor Roc1 as a key regulator of cellulose degradation in the mushroom-forming and wood-degrading fungus Schizophyllum commune. Roc1 is highly conserved in the phylum Basidiomycota. Using comparative genomics, transcriptomics, ChIP-Seq and promoter analysis we have identified direct targets of Roc1, as well as other aspects of the transcriptional response to cellulose.

Objective: The COVID‐19 pandemic has confronted young adults with an unprecedented mental health challenge. Yet, prospective studies examining protective factors are limited. Methods: In the present study, we focused on changes in mental health in a large sample (N = 685) of at‐risk university students, which were measured before and during the pandemic. Network modeling was applied to 20 measured variables to explore intercorrelations between mental health factors, and to identify risk and protective factors. Latent change score modeling was used on a subset of variables. Results: The main findings indicate that (1) mental health problems increased at group level, especially depression‐anxiety and loneliness; (2) emotional support during the COVID pandemic was associated with smaller increases in loneliness and depression‐anxiety; (3) COVID‐related stress predicted increases in depression‐anxiety; (4) loneliness acted as a bridge construct between emotional support and changes in mental health. Conclusion: To mitigate the impact of the COVID‐19 pandemic on the mental health of young adults, is it recommended to focus on interventions that strengthen internal resources (stress‐regulating abilities) and reduce loneliness. [ABSTRACT FROM AUTHOR]

Emerging adulthood is an important developmental phase often accompanied by peaks in loneliness, social anxiety, and depression. However, knowledge is lacking on how the relationships between emotional loneliness, social loneliness, social isolation, social anxiety and depression evolve over time. Gaining insight in these temporal relations is crucial for our understanding of how these problems arise and maintain each other across time. Young adults from a university sample (N = 1,357; M = 23.60 years, SD = 6.30) filled out questionnaires on emotional and social loneliness, social isolation, depressive and social anxiety symptoms at three time points within a 3‐year period. Random intercept cross‐lagged panel models were used to disentangle reciprocal and prospective associations of loneliness subtypes, social isolation, depressive and social anxiety symptoms across time. Results showed that on the within‐person level, increases in emotional and social loneliness as well as social isolation predicted higher depression levels on later timepoints. Increases in depressive symptoms also predicted increases in subsequent social loneliness, but not in emotional loneliness. Finally, increases in depressive symptoms predicted increases in social isolation. There were no significant temporal relations between loneliness and social isolation on the one hand and social anxiety symptoms on the other hand. Social distancing imposed by COVID‐19 related government restrictions may have impacted the current results. The findings suggest that emotional and social loneliness precede development of depressive symptoms, which in turn precedes development of social loneliness and social isolation, indicating a potential vicious cycle of social loneliness, social isolation and depressive symptoms in emerging adulthood. Social anxiety did not precede nor follow loneliness, depressive symptoms, or social isolation. The current study sheds more light on the temporal order of loneliness and psychopathological symptoms and hereby assists in identifying times where prevention and intervention efforts may be especially helpful to counter development of depression and loneliness. [ABSTRACT FROM AUTHOR]

Background: Internet-based cognitive behavioral interventions (iCBTs) are efficacious treatments for depression and anxiety. However, it is unknown whether adding human guidance is feasible and beneficial within a large educational setting., Objective: This study aims to potentially demonstrate the superiority of 2 variants of a transdiagnostic iCBT program (human-guided and computer-guided iCBT) over care as usual (CAU) in a large sample of university students and the superiority of human-guided iCBT over computer-guided iCBT., Methods: A total of 801 students with elevated levels of anxiety, depression, or both from a large university in the Netherlands were recruited as participants and randomized to 1 of 3 conditions: human-guided iCBT, computer-guided iCBT, and CAU. The primary outcome measures were depression (Patient Health Questionnaire) and anxiety (Generalized Anxiety Disorder scale). Secondary outcomes included substance use-related problems (Alcohol Use Disorder Identification Test and Drug Abuse Screening Test-10 items). Linear mixed models were used to estimate the effects of time, treatment group, and their interactions (slopes). The primary research question was whether the 3 conditions differed in improvement over 3 time points (baseline, midtreatment, and after treatment) in terms of depression and anxiety symptoms. Results were analyzed according to the intention-to-treat principle using multiple imputation. Patients were followed exploratively from baseline to 6 and 12 months., Results: In both short-term and long-term analyses, the slopes for the 3 conditions did not differ significantly in terms of depression and anxiety, although both web-based interventions were marginally more efficacious than CAU over 6 months (P values between .02 and .03). All groups showed significant improvement over time (P<.001). For the secondary outcomes, only significant improvements over time (across and not between groups) were found for drug use (P<.001). Significant differences were found in terms of adherence, indicating that participants in the human-guided condition did more sessions than those in the computer-guided condition (P=.002)., Conclusions: The transdiagnostic iCBT program offers a practical, feasible, and efficacious alternative to usual care to tackle mental health problems in a large university setting. There is no indication that human guidance should be preferred over technological guidance. The potential preference of human support also depends on the scale of implementation and cost-effectiveness, which need to be addressed in future trials., Trial Registration: International Clinical Trials Registry Platform NL7328/NTR7544; https://trialsearch.who.int/Trial2.aspx?TrialID=NL-OMON26795., (©Jurrijn Koelen, Anke Klein, Nine Wolters, Eline Bol, Lisa De Koning, Samantha Roetink, Jorien Van Blom, Bruno Boutin, Jessica Schaaf, Raoul Grasman, Claudia Maria Van der Heijde, Elske Salemink, Heleen Riper, Eirini Karyotaki, Pim Cuijpers, Silvia Schneider, Ronald Rapee, Peter Vonk, Reinout Wiers. Originally published in JMIR Mental Health (https://mental.jmir.org), 19.06.2024.)