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Evolutionary relationships among the male and female mitochondrial DNA lineages in the Mytilus edulis species complex 总被引:1,自引:0,他引:1
A novel form of mitochondrial DNA (mtDNA) inheritance has previously been
documented for the blue mussel (Mytilus edulis). Female mussels inherit
their mtDNA solely from their mother while males inherit mtDNA from both
their mother and their father. In males, the paternal mtDNA is
preferentially amplified so that the male gonad is highly enriched for the
paternal mtDNA that is then transmitted from fathers to sons. We
demonstrate that this mode of mtDNA inheritance also operates in the
closely related species M. galloprovincialis and M. trossulus. The
evolutionary relationship between the male and female mtDNA lineages is
estimated by phylogenetic analysis of 455 nucleotides from the large
subunit ribosomal RNA gene. We have found that the male and female lineages
are highly divergent; the divergence of these lineages began prior to the
speciation of the three species of blue mussels. Further, the separation
between the male and female lineages is estimated to have occurred between
5.3 and 5.7 MYA.
相似文献
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Michael J Gramer Ewald TJ van den Bremer Muriel D van Kampen Amitava Kundu Peter Kopfmann Eric Etter David Stinehelfer Justin Long Tom Lannom Esther H Noordergraaf Jolanda Gerritsen Aran F Labrijn Janine Schuurman Patrick HC van Berkel Paul WHI Parren 《MABS-AUSTIN》2013,5(6):962-973
The manufacturing of bispecific antibodies can be challenging for a variety of reasons. For example, protein expression problems, stability issues, or the use of non-standard approaches for manufacturing can result in poor yield or poor facility fit. In this paper, we demonstrate the use of standard antibody platforms for large-scale manufacturing of bispecific IgG1 by controlled Fab-arm exchange. Two parental antibodies that each contain a single matched point mutation in the CH3 region were separately expressed in Chinese hamster ovary cells and manufactured at 1000 L scale using a platform fed-batch and purification process that was designed for standard antibody production. The bispecific antibody was generated by mixing the two parental molecules under controlled reducing conditions, resulting in efficient Fab-arm exchange of >95% at kg scale. The reductant was removed via diafiltration, resulting in spontaneous reoxidation of interchain disulfide bonds. Aside from the bispecific nature of the molecule, extensive characterization demonstrated that the IgG1 structural integrity was maintained, including function and stability. These results demonstrate the suitability of this bispecific IgG1 format for commercial-scale manufacturing using standard antibody manufacturing techniques. 相似文献
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Naaijkens BA Niessen HW Prins HJ Krijnen PA Kokhuis TJ de Jong N van Hinsbergh VW Kamp O Helder MN Musters RJ van Dijk A Juffermans LJ 《Cell and tissue research》2012,348(1):119-130
Adipose-derived stromal cells (ASC) are promising candidates for cell therapy, for example to treat myocardial infarction. Commonly, fetal bovine serum (FBS) is used in ASC culturing. However, FBS has several disadvantages. Its effects differ between batches and, when applied clinically, transmission of pathogens and antibody development against FBS are possible. In this study, we investigated whether FBS can be substituted by human platelet lysate (PL) in ASC culture, without affecting functional capacities particularly important for cardiac repair application of ASC. We found that PL-cultured ASC had a significant 3-fold increased proliferation rate and a significantly higher attachment to tissue culture plastic as well as to endothelial cells compared with FBS-cultured ASC. PL-cultured ASC remained a significant 25% smaller than FBS-cultured ASC. Both showed a comparable surface marker profile, with the exception of significantly higher levels of CD73, CD90, and CD166 on PL-cultured ASC. PL-cultured ASC showed a significantly higher migration rate compared with FBS-cultured ASC in a transwell assay. Finally, FBS- and PL-cultured ASC had a similar high capacity to differentiate towards cardiomyocytes. In conclusion, this study showed that culturing ASC is more favorable in PL-supplemented medium compared with FBS-supplemented medium. 相似文献
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Lake Big Momela, one of the East African soda lakes in Northern Tanzania characterised by highly saline-alkaline conditions, making them inhospitable to a range of organisms, although supporting massive growths of some adapted planktonic microorganisms that serve as food for birds, such as Lesser Flamingo. The temporal dynamics of plankton, with an emphasis on cyanobacteria, were examined in 2007 using morphological traits and ribosomal genetic markers (16S and 18S rRNA). Cyanobacterial genes encoding for hepatotoxins (mcyE and ndaF) were also screened. Rotifers and copepods dominated the zooplankton, whereas cyanobacteria, such as Anabaenopsis elenkinii and Arthrospira fusiformis dominated the phytoplankton community, and these being related to representatives in other East African soda lakes. The cyanobacteria community also showed distinct seasonal patterns influenced by environmental parameters, mainly salinity, pH and nitrate. Significant positive correlations were found between phytoplankton abundance and nitrate concentrations (r = 0.617, p = 0.033). No signals of the hepatotoxin synthetase genes mcyE and ndaF were retrieved from cyanobacteria during the whole year. In general, our data illustrate the presence of rich planktonic communities, including some unique and potentially endemic cyanobacteria. 相似文献
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