Project description:Platelet-rich fibrin (PRF) is prepared from the coagulated plasma of fractionated blood. When squeezing between two plates, PRF is separated into the solid PRF membranes and a liquid exudate, the PRF serum. The question arises regarding the extent to which the overall PRF activity remains in the membranes and what is lost in the serum. To this aim, we have exposed gingival fibroblasts to lysates prepared from PRF membranes and PRF serum, followed by bulk RNA sequencing. A total of 268 up- and 136 down-regulated genes in gingival fibroblasts exposed to PRF lysates are significantly regulated under the premise of a minimum log2 2.5-fold change and a minus log10 significance level of two, respectively. PRF serum caused 62 up- and 32 down-regulated genes when gingival fibroblasts were exposed to PRF serum, respectively. Among the 61 genes commonly up-regulated by PRF lysate and serum were CXCL1, CXCL5, CXCL6, CXCL8, IL33, and IL6 and PTGS2, STC1. PRF lysate further increased the chemokines CCL2, CCL7, CXCL2, CXCL3, and the IL1R1, IL1RL1, and IL1RN – as well as the paracrine factors IL11, LIF, IGF1, BMP2, BMP6, FGF2, CCN2/CTGF and HAS1, HAS2, HAS3. The 16 up-regulated genes by PRF serum included DKK1. Among the 122 down-regulated genes by PRF lysate were IFIT1, IFIT2, IFIT3, OSR1, OSR2. Among the 32 down-regulated genes by PRF serum were FGF18 and GDF15. Taken together, PRF lysates, compared to PRF serum, cause a more complex response of gingival fibroblasts with a chemokine with an obvious increase in chemokine expression and spectrum of paracrine factors.
Project description:BackgroundRhizobium tropici strain PRF 81 (= SEMIA 4080) has been used in commercial inoculants for application to common-bean crops in Brazil since 1998, due to its high efficiency in fixing nitrogen, competitiveness against indigenous rhizobial populations and capacity to adapt to stressful tropical conditions, representing a key alternative to application of N-fertilizers. The objective of our study was to obtain an overview of adaptive responses to heat stress of strain PRF 81, by analyzing differentially expressed proteins when the bacterium is grown at 28°C and 35°C.ResultsTwo-dimensional gel electrophoresis (2DE) revealed up-regulation of fifty-nine spots that were identified by MALDI-TOF/TOF-TOF. Differentially expressed proteins were associated with the functional COG categories of metabolism, cellular processes and signaling, information storage and processing. Among the up-regulated proteins, we found some related to conserved heat responses, such as molecular chaperones DnaK and GroEL, and other related proteins, such as translation factors EF-Tu, EF-G, EF-Ts and IF2. Interestingly, several oxidative stress-responsive proteins were also up-regulated, and these results reveal the diversity of adaptation mechanisms presented by this thermotolerant strain, suggesting a cross-talk between heat and oxidative stresses.ConclusionsOur data provide valuable protein-expression information relevant to the ongoing genome sequencing of strain PRF 81, and contributes to our still-poor knowledge of the molecular determinants of the thermotolerance exhibited by R. tropici species.