Biology subjects

Lanta, V.

Publications and source records attributed to Lanta, V..

3 recordsLinked to original sources

bioRxiv2026

Holobiomes in succession: post-glacial microbial communities are structured by hosts, time and habitat heterogeneity

O_LIGlacier forefields in the high-desert region of Ladakh (northwestern Himalaya) are colonized by a variety of interdependent organisms, including lichens, prokaryotes, fungi, mosses, and vascular plants, along a successional gradient. Together with bulk soil, these hosts and their associated microorganisms form a broader microbial metacommunity (holobiome) whose structure, interactions and functions remain poorly underexplored in one of the Earths most extreme and climate-sensitive environments. C_LIO_LIUsing a multidisciplinary approach combining glacial chronosequence transects, GIS-derived topographic variables, soil properties, and plot cover measurements, we assessed the abiotic and biotic factors influencing bacterial and fungal communities sequenced from different hosts and bulk soil (hereafter sources). Microbial composition was primarily shaped by source identity, though certain sources, such as biological soil crusts (BSCs), mosses, and plant rhizospheres, also showed relationships with moraine age in either bacterial or fungal communities. C_LIO_LIBacterial and fungal community congruence was tested using Procrustes analyses, revealing that mosses maintained tightly coupled inter-kingdom relationships throughout the glacier forefields. However, the degree of congruence in plant rhizospheres and bulk soils was influenced by topographic variation and moraine age, respectively. C_LIO_LICo-occurrence network analyses revealed that early successional microbial communities were assembled more stochastically, with bacteria being more interconnected than fungi. In contrast, late successional stages were more compartmentalized, being more structurally stabile, likely driven by increased plant cover and functional redundancy among microbial taxa. C_LIO_LIKeystone bacterial and fungal taxa were identified in plant rhizospheres and bulk soil using a dual-criteria approach related to inter-kingdom congruence and network node eigenvalues. Furthermore, some of these taxa were associated with environmental factors, suggesting topographic heterogeneity and successional age can promote or deter the influence of keystone taxa. C_LIO_LISynthesis: This study reveals the impact of both macroorganism colonization (i.e. plants, mosses, and lichens) and microcommunity establishment (BSCs and bulk soil), as abiotic and biotic sources, on microbial metacommunity assembly in glacier forefields. By adopting a broader approach across different spatial scales, we demonstrate that while plant colonization plays a central role in shaping microbial metacommunities, its effects are modulated by topographic variation along the chronosequence. C_LI

microbiology↗

bioRxiv2025

When parasites bite hardest: mistletoe effects on oak radial growth peak near climatic optima

Hemiparasitic mistletoes can alter host water and carbon balance, but their impact on tree growth is expected to vary with phenology, microclimate and stand context. We asked whether the yellow mistletoe Loranthus europaeus shifts the timing or reduces the magnitude of radial growth in Quercus robur, and whether any penalty is strongest near climatic optima for host growth. We instrumented 34 mature oaks across age (young, old), canopy position (solitary, closed-canopy), and infection (infected, non-infected) with point dendrometers at 15-minute intervals for four growing seasons (2020-2023). Air and soil temperatures and soil moisture were logged concurrently. We derived growth phenology, difference curves (non-infected minus infected), monthly climate-growth correlations, and response surfaces in temperature- moisture space. Growth phenology was consistent among years: onset around day-of-year 120-140, peak 150-220, cessation 250-270. Mistletoe did not shift onset or cessation but reduced growth amplitude, especially in high-growth years and solitary, well-lit trees. Suppression was greatest near climatic optima ({approx}10-18 {degrees}C with adequate soil moisture) and diminished when conditions were suboptimal (hot and dry or cold and wet), so infected and non-infected converged. Short-term climate-growth relationships were similar across infection status: temperature effects were negative during the main season, whereas soil moisture effects were positive. Young, solitary, non-infected trees responded more to mid-summer moisture than infected trees, consistent with infection shifting hosts from resource-tracking to stress-limited growth under exposure. Joint temperature-moisture response surfaces for infected versus non-infected trees were highly similar, indicating that mistletoe reduces growth magnitude, not niche. Our results identify the environmental window in which host-parasite competition bites hardest and provide a baseline for forecasting parasite impacts under shifting temperature and moisture regimes. Because the largest penalties arise near growth optima, the frequency of cool, moist periods may modulate impacts at the stand scale, particularly for solitary oaks at woodland-grassland ecotones. Integrating fine-scale growth with microclimate clarifies when hemiparasites depress performance and why effects vary across years, sites and canopy contexts. Results underscore the value of continuous dendrometer records for quantifying parasite impacts.

ecology↗

bioRxiv2021

The biosynthesis of phospholipids is linked to the cell cycle in a model eukaryote

The structural challenges faced by eukaryotic cells through the cell cycle are key for understanding cell viability and proliferation. In this study, we tested the hypothesis that the biosynthesis of structural lipids is linked to the cell cycle. If true, this would suggest that the cells structure would form part the control of the cell cycle. Lipidomics (31P NMR and MS), proteomics (Western immunoblotting) and transcriptomics (RT-qPCR) techniques were used to profile the lipid fraction and characterise aspects of its metabolism at seven stages of the cell cycle of the model eukaryote, Desmodesmus quadricauda. We found considerable, transient increases in the abundance of phosphatidylethanolamine during the G1 phase (+35%, ethanolamine phosphate cytidylyltransferase increased 2{middle dot}5x) and phosphatidylglycerol over the G1/pre-replication phase boundary (+100%, phosphatidylglycerol synthase increased 22x). The relative abundance of phosphatidylcholine fell by ~35% during the G1. N-Methyl transferases for the conversion of phosphatidylethanolamine into phosphatidylcholine were not found in the de novo transcriptome profile, though a choline phosphate transferase was found, suggesting that the Kennedy pathway is the principal route for the synthesis of PC. The fatty acid profiles of the four most abundant lipids suggested that these lipids were not generally converted between one another. The relative abundance of both phosphatidylinositol and its synthase remained constant despite an eightfold increase in cell volume. We conclude that the biosynthesis of the three most abundant structural phospholipids is linked to the cell cycle in D. quadricauda.

systems biology↗