Biology subjects

Lin, Y.-C. J.

Publications and source records attributed to Lin, Y.-C. J..

7 recordsLinked to original sources

bioRxiv2024

Living xylem cells encode a large number of conserved gene families responsible for vascular sap peptides

Plant long-distance signaling peptides travel through the vascular system to coordinate development and respond to environmental cues, yet their precursor genes and expression origins remain elusive. We characterized 4,804 sap peptide precursor genes in Populus trichocarpa using an integrated approach that combined liquid chromatography tandem mass spectrometry (LC-MS/MS) peptidomics, transcriptomics, and comparative genomics. This study expands the known precursor families from approximately 50 to thousands, the majority of which are conserved across angiosperms. Transcriptome analysis across xylem developmental stages revealed that living xylem cells, typically viewed as precursors to non-living structures, predominantly express these specifically at transitions between primary and secondary growth stages, indicating an active role in plant-wide signaling coordination. The precursor genes show conservation at the transcriptome level and are under strong purifying selection. Our findings provide a comprehensive overview of the gene families encoding sap peptides, redefining xylem as an active participant in plant communication and adaptation.

plant biology↗

bioRxiv2024

Lignocellulose Degradation in Bacteria and Fungi for Biomass Conversion

Lignocellulose biomass is one of the most abundant resources for sustainable biofuels. However, scaling up the biomass-to-biofuels conversion process for widespread usage is still pending. Bottlenecks during the process of enzymatic hydrolysis are the high cost of enzymes and the labor-intensive need for substrate-dependent enzyme mixtures. Current research efforts are therefore targeted at searching for or engineering lignocellulolytic enzymes of high efficiency. One way is to engineer multi-enzyme complexes that mimic the bacterial cellulosomal system, known to increase degradation efficiency up to 50-fold when compared to freely-secreted enzymes. However, these designer cellulosomes are instable and less efficient than wild type cellulosomes. Fungi cellulosomes discovered in recent years have significant differences from bacterial counterparts and hold great potential for industrial applications, both as designer cellulosomes and as additions to the enzymatic repertoire. Up to date, they are only found in a few anaerobic fungi. In this review, we extensively compared the degradation mechanisms in bacteria and fungi, and highlighted the essential gaps in applying these mechanisms in industrial applications. To better understand cellulosomes in microorganisms, we examined their sequences in 66,252 bacterial species and 823 fungal species and identified several bacterial species that are potentially cellulosome-producing. These findings act as a valuable resource in the biomass community for further proteomic and genetic sequence analysis. We also collated the current strategies of bioengineering lignocellulose degradation to suggest concepts that could be favorable for industrial usage.

microbiology↗

bioRxiv2024

Evolutionary conserved sap peptides derived from xylem-specific peptide precursors in woody angiosperms

Peptides act as long-distance mobile signals, transported through vascular sap to coordinate complex developmental processes. Since the tissue-specificity of peptide precursor gene expression is critical in determining peptide signaling function, we integrated vascular sap peptidomes with tissue-level transcriptomes to investigate the roles of sap peptides in two economically important woody plants, Populus trichocarpa and Eucalyptus grandis. Xylem exhibited the highest ratio of tissue-specific sap peptide precursor genes. Most of the sap peptides derived from xylem-specific precursor genes of P. trichocarpa and E. grandis were highly conserved throughout woody species selected from different clades in angiosperms, including magnoliids, rosids and asterids in eudicots. To further explore the conservation of these peptides, we examined the sap peptidome of Cinnamomum kanehirae (camphor tree), from the ancient clade with three xylem cell types. Approximately 90% of the peptides from xylem-specific precursors that were conserved between P. trichocarpa and E. grandis, were also conserved in the vascular sap of C. kanehirae, demonstrating a remarkably high conservation of these peptides across woody angiosperms. Most of the sap peptides conserved in these three woody species are also highly conserved across land plants, suggesting that these peptides may contribute to plant terrestrialization. Within the sap peptides from xylem- specific precursor genes, a total of 10 peptides were identical across all three woody plants. This substantial enrichment of xylem-specific precursor-derived peptides, along with their high conservation, suggests that these long-distance mobile peptides play a crucial role in secondary xylem development. One sentence summaryIntegration of sap peptidomic and tissue-level transcriptomic data revealed highly conserved long-distance mobile peptides derived from xylem- specific precursors across woody angiosperms.

evolutionary biology↗

bioRxiv2024

A Sap Peptide Conserved across Flowering Plants Positively Regulates Lignin Biosynthesis, Biomass and Immunity

Signaling peptides act as hormones to deliver short- or long-distance intercellular signals to govern complex developmental processes. Identifying endogenous signaling peptides is challenging due to their low abundance and the unknown cleavage sites required for release from precursor proteins, not to mention the investigation of their evolutionary roles across species. Consequently, very few peptides were evolutionarily characterized in vivo, especially long-distance signaling peptides. Here we present current largest peptidomic datasets from six species (maize, camphor tree, tomato, rose gum, soybean and poplar), totaling 12,242 peptides, selected from all representative evolutionary clades of angiosperms, including monocots, magnoliids, rosid eudicots, and asterid eudicots. A sap peptide was found to be identical across all six species and named as ASAP (angiosperm sap peptide), emerging as the most conserved peptide family discovered thus far. ASAP rapidly induces a series of protein phosphorylation involved in a signaling cascade previously reported to regulate lignin biosynthesis, plant growth and plant immunity. Functional assays on ASAP activity demonstrated its capability on the induction of monolignol biosynthesis and lignin deposition. High-throughput phenomic analyses showed that ASAP significantly increased plant above- and below-ground biomass. In addition, ASAP treatment enhanced plant immunity and reduced the number of galls and egg masses against nematode invasion. This study provides insights into the conservation and functional significance of plant long-distance mobile signaling peptides, offering potential applications in crop improvement and disease management strategies.

plant biology↗

bioRxiv2023

An acidophilic fungus is integral to prey digestion in a carnivorous plant

Carnivorous plant leaves, such as those of the spoon-leaved sundew Drosera spatulata, secrete mucilage which hosts microorganisms potentially aiding in prey digestion. We characterised the mucilage microbial communities and identified the acidophilic fungus Acrodontium crateriforme as the ecologically dominant species. The fungus grows and sporulates on sundew glands as its preferred acidic environment. We show that the A. crateriforme has a reduced genome similar to that of other symbiotic fungi. Based on the transcriptomes when encountering prey insects, we revealed a high degree of genes co-option in each species during fungus-plant coexistence and digestion. Expression patterns of the holobiont during digestion further revealed synergistic effects in several gene families including fungal aspartic and sedolisin peptidases, facilitating the digestion of sundews prey, as well as transporters and dose-dependent responses in plant genes involved in jasmonate signalling pathway. This study establishes that botanical carnivory is defined by multidimensional adaptations correlated with interspecies interactions.

microbiology↗

bioRxiv2022

The 24-chain core-shell nanostructure of wood cellulose microfibrils in seed plants

Wood cellulose microfibrils (CMFs) are the most abundant organic substance on earth, but their nanostructures are poorly understood. There are controversies regarding the glucan chain number (N) of CMFs during initial synthesis and whether they become fused afterwards. Here, we combined small-angle X-ray scattering (SAXS), solid-state nuclear magnetic resonance (ssNMR) and X-ray diffraction (XRD) analyses to resolve these controversies. We successfully developed SAXS measurement methods for the cross-section aspect ratio and area of the crystalline-ordered CMF core, which showed higher density than the semi-disordered shell. The 1:1 aspect ratio suggested that CMFs remain mostly segregated, not fused. The area measurement revealed the chain number in the core zone (Ncore). The ratio of ordered cellulose over total cellulose, termed Roc, was determined by ssNMR. Using the formula N = Ncore / Roc, we found that the majority of wood CMFs contain 24 chains, conserved between gymnosperm and angiosperm trees. The average wood CMF has a crystalline-ordered core of [~]2.2 nm diameter and a semi-disordered shell of [~]0.5 nm thickness. In naturally and artificially aged wood, we only observed CMF aggregation (contact without crystalline continuity) but not fusion (forming conjoined crystalline unit). This further argued against the existence of partially fused CMFs in new wood, overturning the recently proposed 18-chain fusion hypothesis. Our findings are important for advancing wood structural knowledge and more efficient utilization of wood resources in sustainable bio-economies.

plant biology↗

bioRxiv2021

Single-cell transcriptomics unveils xylem cell development and evolution

As the most abundant tissue on Earth1, xylem is responsible for lateral growth in plants. Typical xylem has a radial system composed of ray parenchyma cells and an axial system of fusiform cells2. In most angiosperms, fusiform cells are a combination of vessel elements for water transportation and libriform fibers for mechanical support, while both functions are performed together by tracheids in other vascular plants2. However, little is known about the developmental programs and evolutionary relationships of these xylem cell types. Through both single-cell and laser-capture microdissection transcriptomic profiling, here we demonstrate the developmental lineages of ray and fusiform cells in stem-differentiating xylem across four divergent woody angiosperms. Cross-species analyses of single-cell trajectories reveal highly conserved ray, yet variable fusiform, lineages across angiosperms. Core eudicots Populus trichocarpa and Eucalyptus grandis share nearly identical fusiform lineages. The tracheids in the basal eudicot Trochodendron aralioides, an evolutionarily reversed character3, 4, exhibit strong transcriptomic similarity to vessel elements but not libriform fibers, suggesting that water transportation, instead of mechanical support, is the major feature. We also found that the more basal angiosperm Liriodendron chinense has a fusiform lineage distinct from that in core eudicots. This evo-developmental framework provides a comprehensive understanding of the formation of xylem cell lineages across multiple plant species spanning over a hundred million years of evolutionary history5.

plant biology↗