Biology subjects

Wang, J. A.

Publications and source records attributed to Wang, J. A..

6 recordsLinked to original sources

bioRxiv2026

Prior low-severity fires reduce the risk of persistent forest loss from subsequent fires

Intensifying fire regimes threaten forests globally, but the risk of persistent post-fire forest loss and its potential mitigation remains poorly quantified. We analyzed millions of wildfires worldwide from 2001 to 2024 and tracked recovery in satellite-observed forest structure and ecosystem function. Post-fire persistent forest loss, indicated by modeled non-recovery to pre-fire conditions over decadal timescales, affected 57.1% of burned forest area globally since 2001, with hotspots in Pacific temperate and southern boreal forests. We then identified 'crucial fires' as events exceeding a stringent modeled-risk probability threshold for persistent structural or functional non-recovery, with fire severity strongly predicting this loss. This severity dependence revealed a management pathway, as locations with prior low-severity fire experienced lower severity in subsequent wildfires and had lower modeled probability of becoming crucial. Under a model-based counterfactual scenario, applying the estimated severity attenuation was associated with a 7.6% reduction; the top 1% of road-accessible areas accounted for 35% of this reduction. These results provide a global framework for identifying where wildfire threatens forest resistance and where targeted low-severity fire management like prescribed fire might be used to combat global forest loss.

ecology↗

bioRxiv2026

A global analysis of climate-driven reversal risks in forests

The integrity of forest-based climate solutions and carbon credits requires persistent carbon storage, but climate change is increasing the risk of natural disturbances that release carbon back into the atmosphere. Using global satellite data, disturbance modeling, and machine learning, we provide the first spatially explicit and scenario-based maps of long-term probability of carbon loss in global forests under different disturbance severities and climate scenarios. We find that North American conifer forests, tropical rainforests, and Asian (sub)tropical dry forests face the greatest risks, and that Eurasian temperate forests, African (sub)tropical dry forests face the lowest. Globally, the likelihood of reversals over 100 years is 31%-42% across all scenarios. Our work helps to maximize the benefits of forest-based climate solutions by informing more strategic project placement and more robust reversal-risk compensation mechanisms, such as buffer pools, and highlights critical additional science to better understand and manage risks of these essential climate solutions. Plain Language SummaryForests can help slow and lessen climate impacts. However, in places this benefit is becoming less reliable as climate change increases natural disturbances such as wildfires, drought, storms, and insect outbreaks, which can release stored carbon back into the atmosphere. In this study, we created the first scenario-based global maps of risks and found that the risk of carbon loss is widespread and highly variable across regions, with especially high vulnerability in North American conifer forests, tropical rainforests, and Asian tropical and subtropical dry forests. Our study highlights the importance of considering disturbance risks when siting forest projects for climate mitigation, and developing protocols for carbon markets, such as in voluntary programs and under the UNFCCC Paris Agreement. Key PointsO_LIA demographic model framework estimates the reversal risk from natural disturbances over 100 years in global forests C_LIO_LISpatially explicit maps under different severity scenarios show variation in the integrated 100-year risk of carbon reversal C_LIO_LISpatially explicit maps estimate the required buffer pool needed to compensate for disturbance-driven reversals in global forests C_LI

ecology↗

bioRxiv2025

An AGO2 adaptor expands the functional and evolutionary reach of microRNA targeting

Current models of microRNA (miRNA) silencing posit that RNA-sequence rules are sufficient for canonical targeting of mRNAs by Argonaute 2 (AGO2), the central protein of the miRNA-induced silencing complex (miRISC). Using chimeric eCLIP in CRISPR-edited LIMD1+/+, LIMD1+/-, and LIMD1-/- human small airway epithelial cells (hSAECs), we reveal a transcriptome-wide dependency on LIMD1, an AGO2 adaptor, for effective miRNA targeting and repression. In LIMD1-deficient cells, miRNA loading is uncoupled from productive targeting: despite increased AGO2-miRNA interactions, complexes engage fewer transcripts and sites, reducing occupancy and more than halving both the breadth and depth of targeting. We also observe altered AGO2 positional footprints across targets in LIMD1-deficient cells. LIMD1 dependence is most pronounced at defined RNA contexts: weak (GC-poor) seed pairings, interactions involving evolutionarily young miRNAs or sites that nonetheless form thermodynamically stable duplexes, with these losses particularly enriched in coding sequences of rapidly evolving C2H2-zinc-finger genes. Even within canonical seed repertoires of individual AGO2-miRNAs, LIMD1 is most critical at poorly conserved sites, indicating that LIMD1 broadens miRNA regulation beyond ancient, deeply conserved targets. In culture, LIMD1 deficiency de-represses oncogenic proteins that, in vivo, inversely correlate with LIMD1 levels in normal lung and adenocarcinoma, where LIMD1 is characteristically reduced, and whose dysregulation predicts poor survival. Thus, LIMD1 emerges as a key determinant of miRISC architecture, targeting, and potency, challenging RNA-centric models of miRNA function and exemplifying how adaptor proteins diversify post-transcriptional regulation. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=180 HEIGHT=200 SRC="FIGDIR/small/680889v2_ufig1.gif" ALT="Figure 1"> View larger version (58K): org.highwire.dtl.DTLVardef@e0f4f5org.highwire.dtl.DTLVardef@f23fd9org.highwire.dtl.DTLVardef@3de3f2org.highwire.dtl.DTLVardef@1404af2_HPS_FORMAT_FIGEXP M_FIG LIMD1 defines the scope of miRNA-mediated targeting and repression O_LIAGO2-chimeric eCLIP in CRISPR-edited human small airway epithelial cells (hSAECs) shows LIMD1 is required for productive AGO2-miRNA engagement transcriptome-wide. C_LIO_LILIMD1 deficiency reduces the AGO2-miRNA:targetome. Each AGO2-miRNA binds fewer targets, with lower occupancy per site and per transcript and fewer global silencing events. C_LIO_LILIMD1 dependence is strongest for GC-poor seed-sites, less conserved miRNAs and sites, and thermodynamically stronger duplexes. C_LIO_LIDosage-dependent effects of LIMD1 deficiency are broadly observed. C_LIO_LITarget-mRNA decay and translational repression are reduced in LIMD1-deficient hSAECs, increasing protein output. C_LIO_LIIn vivo, LIMD1 LOH-associated deficiency is prevalent and typically clonal in NSCLC. LIMD1 expression inversely correlates with oncogene levels in normal lung and adenocarcinoma, and target dysregulation predicts poor survival. C_LI C_FIG

molecular biology↗

bioRxiv2025

Accelerated biomass loss in western US forestlands due to shifting fire regime

Wildfires influence the distribution of biomass across the Earths surface and drive losses of carbon from the land surface to the atmosphere. Although the global budget between terrestrial and atmospheric carbon pools is comparatively well understood (Jones et al., 2024; MacCarthy et al., 2024), the growing size and severity of wildfires present an increasing challenge to regional carbon accounting. To quantify vegetation biomass across arid systems in the western US, we used remote sensing data to estimate the aboveground live biomass density (Mg ha-1) at 30-meter resolution across the states of Utah and Nevada annually from 2000 to 2022. Time series biomass maps showed accelerated loss of terrestrial carbon to the atmosphere as a result of increasing wildfire, with annual biomass burnt increasing at 0.105 {+/-} 0.024 Mt yr-1 (mean {+/-} standard deviation) after 2015. Recent shifts in the wildfire regime show a transition from predominantly early-season fires in low-biomass grasses and shrubs to late-season fires in higher-biomass forestlands. The proportion of total biomass loss attributed to wildfires in forestland areas increased from an average of 76% per year before 2015 to 94% in the years that followed. Furthermore, we found that recent droughts contributed to increased biomass loss in forestland areas, whereas biomass in non-forestland areas appeared unaffected by drought conditions. These findings underscore the escalating impact of climate change on fire regimes, highlighting the urgent need for adaptive land management strategies to mitigate carbon loss and preserve ecosystem resilience in the face of ongoing aridification.

ecology↗

bioRxiv2024

YAP engages RIF1 to dampen replication stress in squamous cell carcinoma.

Squamous cell carcinoma cells experience high levels of replication stress due to oncogene-induced cell cycle deregulation. How such cells sustain rapid proliferation despite replication stress is still not fully understood. Here, we discovered, using rapid immunoprecipitation mass spectrometry of endogenous protein (RIME) analysis, that the squamous cell carcinoma oncoprotein YAP engages with RIF1, a key regulator of DNA replication and DNA damage repair under replication stress. RIF1 is highly expressed in human squamous cell carcinoma cell lines and tissues and upregulated during tumour progression. Depletion of RIF1 in squamous cell carcinoma cells exacerbates their endogenous replication stress. Mechanistically, we show that YAP interacts with RIF1 specifically at broken replication forks, and that YAP depletion impairs DNA damage repair under replication stress. Our results thus demonstrate that YAPs oncogenic functions in squamous cancers involve both transcriptional and non-transcriptional mechanisms, the latter through interaction with RIF1 to dampen replication stress.

cancer biology↗

bioRxiv2021

Remote sensing reveals multi-decadal losses of tree cover in California driven by increasing fire disturbance and climate stress

Forests provide natural climate solutions for sequestering carbon and mitigating climate change yet are threatened by increasing temperatures and disturbance. Accurate information on vegetation dynamics is lacking in some regions with forest carbon offset programs and dense forests like California. To address this, we combined remote sensing observations with geospatial databases to develop annual maps of vegetation cover (tree, shrub, herbaceous) and disturbance type (fires, harvest, and forest die-off) in California at 30 m resolution from 1985 to 2021. California lost 3783 km2 of its tree cover area (5.5% relative to initial cover). Early gains in tree cover area were more than offset by fire-driven declines, resulting in greater shrub and herbaceous cover area. Fires and tree cover area loss occurred where temperatures were high or increasing, whereas tree cover gain occurred in cooler areas. Disturbance and warming are threatening the integrity of Californias forests and its carbon offsets program. TeaserClimate and disturbance-driven tree cover loss challenges the viability of forests as natural climate solutions in California

ecology↗