Biology subjects

Mooney, B. P.

Publications and source records attributed to Mooney, B. P..

3 recordsLinked to original sources

bioRxiv2025

Enhanced cell aggregation in the Chlamydomonas reinhardtii rbo1 mutant in response to multifactorial stress combination

Global change factors associated with climate change and increased pollution are subjecting plants, microbes, and different ecosystems to conditions of multifactorial stress combination (MFSC). While recent studies centered on the effects of MFSC on different plants and ecosystems, much less is known about how these conditions impact unicellular organisms. Here, we report on the physiological and proteomic responses of wild type and respiratory burst oxidase homolog 1 (rbo1) mutant cells of Chlamydomonas reinhardtii to a MFSC of 5 different abiotic stresses. While several similarities were found between plant and C. reinhardtii responses to MFSC, our work revealed that MFSC induces aggregation in the unicellular organism C. reinhardtii. We further show that MFSC induced aggregation is enhanced in the rbo1 mutant and can be triggered by H2O2. As aggregation typically leads to reduced growth, respiration and/or photosynthesis, enhanced aggregation of unicellular organisms in different ecosystems subjected to MFSC could explain part of the negative impacts of MFSC on the services they provide. Our findings shed new light on the response of unicellular organisms to MFSC and suggest that one of the main drivers leading to multicellularity during evolution was early conditions of MFSC under an oxygenated environment.

plant biology↗

bioRxiv2023

Comparative omics reveals unanticipated metabolic rearrangements in a high-oil mutant of plastid acetyl-CoA carboxylase

Heteromeric acetyl-CoA carboxylase (ACCase) catalyzes the ATP-dependent carboxylation of acetyl-CoA to produce malonyl-CoA, the committed step for de novo fatty acid synthesis. In plants, ACCase activity is controlled at multiple levels, including negative regulation by biotin attachment domain-containing (BADC) proteins, of which the badc1/3 double mutant leads to increased seed triacylglycerol accumulation. Unexpectedly, the Arabidopsis badc1/3 mutant also accumulates more protein. The metabolic consequences from both higher oil and protein was investigated in developing badc1/3 seed using global transcriptomics, translatomics, proteomics, and metabolomics. Changes include: reduced plastid pyruvate dehydrogenase; increased acetyl-CoA synthetase; increased storage and lipid-droplet packaging proteins; increased lipases; and increased {beta}-oxidation fatty acid catabolism. We present a model of how Arabidopsis adapted to deregulated ACCase, limiting total oil accumulation, and altering flux through pathways of carbon accumulation that presents possible targets for future bioengineering of valuable seed storage reserves.

plant biology↗

bioRxiv2021

Integrative proteomics and phosphoproteomics reveals phosphorylation networks involved in the maintenance and expression of embryogenic competence in sugarcane callus

Sugarcane (Saccharum spp.) is one of the most important crops for sugar, biofuel, and bioenergy production and has become an important commodity in the worldwide agricultural market in more than 100 countries. In this study, label-free quantitative proteomics and phosphoproteomics analyses were performed to investigate signaling events related to somatic embryo maturation and differentiation in sugarcane. Embryogenic callus (EC) at multiplication (EC0) and after 14 days (EC14) of maturation were compared. The EC14/EC0 comparison found that 251 phosphoproteins and 700 proteins were differentially regulated and accumulated, respectively. Metabolic pathway analysis showed that these proteins and phosphoproteins were enriched in lysine degradation and starch/sucrose metabolism during multiplication, whereas the differentiation of somatic embryos was found to involve the regulation of energetic metabolism, including the TCA cycle, oxidative phosphorylation, and carbon metabolism. Multiplication-related phosphoproteins were mainly associated with abscisic acid responses and transcriptional regulation of the TOPLESS (TPL), SNF1 kinase homolog 10 (KIN10), SEUSS (SEU), and LEUNIG_HOMOLOG (LUH) proteins. Among the maturation-related phosphoproteins, the phosphorylation of light harvesting complex photosystem ii, CURVATURE THYLAKOID 1B, vacuolar proton ATPase A1 and phytochrome interacting factor 3-LIKE 5 was found to be associated with bioenergetic metabolism and carbon fixation. A motif analysis revealed 15 phosphorylation motifs, and among these, the [D-pS/T-x-D] motif was unique among the phosphopeptides identified during somatic embryo differentiation. A coexpression network analysis of proteins and phosphoproteins revealed interactions among SNF1-related protein kinase 2 (SnRK2), abscisic acid responsive elements-binding factor 2 (ABF2), and KIN10, which indicated the role of these proteins in embryogenic competence in EC0. The interactions among ubiquitin-conjugating enzyme 5, ubiquitin-conjugating enzyme 35, small ubiquitin-like modifier 1, and histone deacetylase 1 may be involved in posttranslational protein modification during embryo maturation. Argonaute 1 (AGO1) also interacts with POLTERGEIST (POL) and may integrate gene silencing with the regulation of meristem identity during somatic embryo development. These results reveal novel dynamics of protein regulation in somatic embryogenesis and identify new potential players in somatic embryo differentiation and their phosphosites.

plant biology↗