Alternative splicing of medaka bcl6aa and its repression by Prdm1a and Prdm1b
Summary (2 min read)
Possible Mechanisms of Oxygen Exchange for Dual Phase Composites
- Oxygen exchange on dual-phase composites have been discussed by several groups as mentioned in the introduction.
- Different involvements of the two phases in the oxygen exchange were proposed.
- S1 is the surface area of the P1 phase, V1 is the volume of P1, t is time and k1 is the efficient surface exchange coefficient of the P1 phase.
- The kex-LSF (GB) and kex-CGO (GB) are the effective surface exchange coefficient on the single-phase grain boundaries and kex(TPB) is the effective surface exchange coefficient on the dual-phase grain boundaries (as illustrated in Figure 2II).
- The oxygen exchange on the “cleaned” CGO surface appears to be very fast,40 and possibly, in the older SIMS studies of single phase CGO the exchange reaction has been impeded by unintended impurities on CGO surface.
Experimental
- The sample was sintered at 1300◦C for 10 h to reach 97.4% of the theoretical density, polished and re-annealed at 1000◦C. Characterizations.
- Pt wires attached to both ends of the sample were used as current probes.
- By fitting the conductivity change using Fick’s law of diffusion with appropriate boundary conditions, the values of kex and Dchem can be obtained.
Results
- —The X-ray diffractograms of the pure LSF, the dual-phase LSF-CGO composites after sintering at 1300◦C and of the CGO powder are shown in Figure 3.
- The total conductivity of the composites is lower than that of the pure LSF, due to much lower total conductivity of CGO (Table I).
- At 750◦C the measured values correspond well to the calculated one with τIC of 1 for the CGO70 sample, whereas τIC of 2.5 and 20 were used for the CGO50 and CGO30 samples, respectively (Figure 8B) to match the measured and calculated Dchem values.
- Assuming that oxygen exchange may also occur on the CGO, the effective kex(cal) was calculated according to Eq. 3, where the kex(CGO) was selected as to give a best fit of Eq. 3 to the measured values for different temperatures and pO2’s.
Discussion
- In case of pure LSF the surface exchange reaction at high pO2’s (10−3 < pO2 < 1 atm), by assuming the involvement of oxygen vacancies in the oxygen surface exchange process,10 will be strongly depended on the mobility and/or concentration of oxygen vacancies, while for pure CGO the oxygen exchange will be presumably limited by the electronic conductivity.
- Hence, it could be, that a cleaning of the CGO surface takes place via the presence of LSF, making the oxygen exchange on CGO much faster than when considering single phase CGO samples.
- It should also be pointed out that these two mechanisms are not mutually exclusive and can act simultaneously. ) unless CC.
- Further, the pO2 dependence of kex, which was observed to vary with the CGO fraction and the temperature, can point out different aspects of the mechanism of the oxygen exchange.
- At 750◦C the measured values for the CGO70 sample behaves as expected from the materials properties and increasing the LSF fraction leads to large deviations from the values obtained by volume weighting average, which is interpreted as a tortuosity effect.
Conclusions
- Considering all experimental data it is further suggested that the rds is temperature and composition dependent.
- The involvement of CGO in the oxygen exchange can be through the spillover of oxygen ions, partly reduced oxygen species, from LSF to CGO, where they dissociate and/or incorporate.
- An alternative effect could be that the LSF scavenges impurities from CGO and thereby activates the CGO surface for the oxygen surface exchange reaction.
- Both proposed mechanism could account for the observations.
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"Alternative splicing of medaka bcl6..." refers background or methods or result in this paper
...Although the expression of prdm1a, prdm1c, and bcl6aa had been reported previously (Zhang et al. 2019b; Zhao et al. 2014), the expression of prdm1b and the alternative splicing variants of bcl6aa are not reported yet in medaka....
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...The homologs of Bcl6 have been reported in several sh including fugu (Odaka et al. 2011; Ohtani et al. 2006b), zebra sh (Lee et al. 2013), medaka (Zhang et al. 2019b), grass carp (Zhu et al. 2019), and Senegalese sole (Solea senegalensis) (Ponce et al. 2020)....
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...…of 28.0°C. Adult sh were randomly divided into three groups and were injected intraperitoneally with 10 µl of phosphate buffer solution (PBS), LPS (Sero-type: O55:B5, Sigma-Aldrich, Merck KGaA, Darmstadt, Germany), polyI:C (Sigma-Aldrich), respectively (Zhao et al. 2014; Zhang et al. 2019)....
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...Bcl6aa was also detected in the immune tissues and embryos of medaka as reported previously (Zhang et al. 2019b)....
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...The alternative splicing of bcl6b was also identi ed in medaka (Zhang et al. 2019a)....
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4 citations
"Alternative splicing of medaka bcl6..." refers background in this paper
...STAT3 (Signal transducer and activator of transcription 3) can upregulate PRDM1 coordinately with down-regulation of BCL6 to control human plasma cell differentiation (Diehl et al. 2008)....
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...As a homolog of BCL6, Bcl6aa must be translocated into the cell nucleus....
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...Fish Shell sh Immunol 27: 414-422 Diehl SA, Schmidlin H, Nagasawa M, van Haren SD, Kwakkenbos MJ, Yasuda E, Beaumont T, Scheeren FA, Spits H (2008) STAT3-mediated up-regulation of BLIMP1 is coordinated with BCL6 down-regulation to control human plasma cell differentiation....
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...The different isoforms may still repress their target genes as reported in human BCL6 and BCL6s (Shen et al. 2008)....
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...An isoform of human BCL6, BCL6S lacking the rst two ZFs still represses the target genes of BCL6 (Shen et al. 2008)....
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3 citations
"Alternative splicing of medaka bcl6..." refers background in this paper
...Phosphorylation can regulate protein folding, protein-protein interaction, localization, stability, and activity (Liu et al. 2020; Narayanan and Jacobson 2009; Nishi et al. 2011)....
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2 citations