Golim, M. d. A. | bioRxiv Science

bioRxiv2021

The ethanol tolerance in Saccharomyces cerevisiae under a phenomics perspective

Ethanol (EtOH) is a substantial stressor for Saccharomyces cerevisiae. Data integration from strains with different phenotypes, including EtOH stress-responsive lncRNAs, are still not available. We covered these issues seeking systems modifications that drive the divergences between higher (HT) and lower (LT) EtOH tolerant strains under their highest stress conditions. We showed that these phenotypes are neither related to high viability nor faster population rebound after stress relief. LncRNAs work on many stress-responsive systems in a strain-specific manner promoting the EtOH tolerance. Cells use membraneless RNA/protein storage and degradation systems to endure the stress harming, and lncRNAs jointly promote EtOH tolerance. CTA1 and longevity are primer systems promoting phenotype-specific gene expression. The lower cell viability and growth under stress is a byproduct of sphingolipids and inositol phosphorylceramide dampening, acerbated in HTs by sphinganine, ERG9, and squalene overloads; LTs diminish this harm by accumulating inositol 1-phosphate. The diauxic shift drives an EtOH buffering by promoting an energy burst under stress, mainly in HTs. Analysis of mutants showed genes and lncRNAs in three strains critical for their EtOH tolerance. Finally, longevity, peroxisome, energy and lipid metabolisms, RNA/protein degradation and storage systems are the main pathways driving the EtOH tolerance phenotypes.

systems biology↗

bioRxiv2019

Improvement of bone regeneration using fibrin biopolymer combined with differentiated stem cells

1.Bone tissue repair remains a challenge on tissue engineering. New approaches are highly expected to regenerate fractures, bone infections, cancers and congenital skeletal abnormalities. Lately, osteoconductive biomaterials have been used with osteoprogenitor cellsas bone substitutes to accelerate bone formation. Fibrin scaffold serves as a provisional platform promoting cell migration and proliferation, angiogenesis, connective tissue formation and growth factors stimulation. When combined with mesenchymal stem cells (MSCs) maintain cell viability that exerts an immunomodulatory effect by modifying inflammatory environment through expression of pro and anti-inflammatory cytokines. We evaluated a unique heterologous fibrin biopolymer as scaffold to MSCs on bone regeneration of rat femurs. A critical-size bone defect was made in the femur and treated with fibrin biopolymer(FBP); FBP + MSC; and FBP + MSC differentiated in bone lineage (MSC-D). Bone repair was analyzed 03, 21 and 42 days later by radiographic, histological and scanning electron microscopy (SEM) imaging. The FBP+MSC-D association was the most effective treatment, since newly formed bone was more abundant and early matured in just 21 days. Our results demonstrate that FBP isolated was able to promote bone repair although cells play a crucial role on the type and quantity of bone tissue formed. We have not observed surgical site infection, inflammatory response, fractures or loss of function related with FBP. Thus, this approach can be safely expanded for clinical trials as an effort to overcome current method limitations and improve overall bone regeneration process.

bioengineering↗